Ultimate Guide to Budget BBC Cylinder Heads Under $2,000 (WHENEAGLESFLY) posted this
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the upper closed chamber head is bath tube shaped to provide dual opposed quench areas that squish against the piston deck,
forcing the fuel air mix toward the central cylinder bore, the lower open chamber head combustion chamber was found to un-shroud the valves,\
thus increasing the cylinder fill efficiency especially at upper rpms.
the dome higher compression ratio pistons for both combustion chambers are similar in shape to the combustion chambers they are designed too be used with.
the closed chamber piston can be used with the larger open chamber combustion chamber , but its reduced volume results in less effective compression and the dome,
of the closed chamber dome is marginally restrictive to the flame front propagation.
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In general terms,
big engines make big power! It stands to reason that if you want earth shaking, ground pounding power, you probably want to build a big block engine. Power, however, comes at a price. The old adage of “there’s no replacement for displacement” still holds true, but cubic inches of power doesn’t have to cost you cubic dollars. The high performance aftermarket has seen an influx of big block Chevy cylinder heads, many of which can fit into the tightest of budgets and still bring thundering punishment to the pavement.
When you are putting together the big block puzzle, one of the worse things you can do is buy whatever part is on sale this week. Randomly buying parts because they look good or because they have good street cred may cost you more in the long run. Big Block Chevy cylinder heads are a perfect example of where money spent wisely can pay off with some decent power without spending your kid’s entire college fund. Power does come at a price, but you can make some wise choices that produce the power you are expecting by picking up affordable heads.
With some smart shopping techniques, like knowing what your overall goal is, you can purchase a set of cylinder heads without breaking the bank, and more importantly, without compromising on power. To help answer the question of “What cylinder head do I need for my big block Chevy?”we have assembled a guide that will help you get through the dense jungle growth of BBC cylinder head choices. Follow along as we go for a run through the jungle.
The Key to Finding the Right Cylinder Head
RHS’ Product Manager Kevin Feeney summed up the process of finding the right set of heads for your BBC, “The first step is to determine what you are trying to accomplish with the engine. Are you looking for torque or horsepower, or the best combination of them both? This and the size of the engine are vital to choosing the proper runner sizes, valve sizes and ports for the application.”
With so many variables, and so many choices, it’s easy to go down the wrong path or find a shortcut to less performance. “Too many times guys tend to buy cylinder heads based on high lift flow numbers that are easily achieved with large ports and valves, but do not necessarily provide them with the performance they are looking for,” added Feeney.
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Cast Iron being poured into molds at the foundry. (Photo from CFM Corporation)
What this Guide Covers
Our comprehensive guide to budget-friendly big block cylinder heads is strictly limited to fully configured and assembled units that are sold as a set for under $2,000 and are perfect for street use. We limited the spectrum of head choices to engines that are designed to run 91 octane pump gas and are not trailer queens. If you’re building a car that you can’t drive to the track, you’re probably not looking for a budget friendly set of cylinder heads anyway and this guide won’t cover the range of cylinder heads that you are looking for.
Our Criteria for budget friendly:
- A fully configured and assembled set of cylinder heads
- Priced under $2,000
- Street or Street/Strip use
- Designed to run on pump gas
- Must be able to make more power than stock OEM cylinder heads
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Take a look at the big picture before rushing out to buy the first set of BBC heads you see.
Factors To Consider
There are several factors to consider when selecting the right set of heads for your big block. Dart Machinery’s Advertising Director, Jack McInnis explained “The size of the engine, rpm range, camshaft, type of fuel, weight and gearing all factor in. Whether the car will be street driven 99% of the time, or if it will be primarily raced and driven on the street only occasionally will make a big difference in the choice as well.” Armed with McInnis’ warning to take a look at the whole picture, we have broken down some of the basic characteristics that you need to consider when selecting a budget big cube head.
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Aluminum heads look great and have a lot of good things going for them, but are they right for you?
Aluminum VS. Cast Iron
Cast iron is pretty common to most of us because it has been around the longest. Cast iron is inexpensive when compared to aluminum and is strong and durable. There are hundreds of different cast iron alloys but the kind that is typically used in cylinder heads is a gray cast iron. Gray cast iron is generally about 92-percent iron, 3.4 percent carbon, 2.5 percent silicon and 1.8 percent manganese. Rated at a tensile strength around 25,000 psi and a hardness somewhere near 180 on the Brinnell scale, cast iron heads are heavier than aluminum heads and can weigh as much as 30 percent more.
Aluminum’s main advantage is its light weight. Aluminum also dissipates heat very quickly, which may or may not be an advantage, depending on what you are trying to achieve. To make horsepower, you want some heat to be retained in the combustion chamber without detonation or preignition, which makes aluminum a great choice.
We talked to Billy Briggs of Briggs Performance about aluminum heads. “About the only drawback with aluminum is the simple fact that the aluminum alloy itself only has a life span of so long, but the pros are still huge. Ease of repair, ease of machining, heat dissipation and lighter weight are just a few,” said Briggs.
Aluminum alloys have become much better in recent years and the problems associated with heat warping aluminum heads in the early 1980s have been eliminated. There are some installation procedures that should be adhered to when installing aluminum cylinder heads for trouble free service.
Chad Golen of Golen Performance, a top notch GM LS engine builder, explained, “Aluminum has more expansion but doesn’t cause a problem with today’s head gaskets and high quality fasteners made by ARP. You just need to be careful bolting up accessories, like intakes and valve covers so you don’t damage the threads.”
Another company that specializes in big block Chevy heads is Livernois Motorsports in Michigan. Mike Schropp, Engine Department Supervisor at Livernois, confirmed that, “While aluminum heads do contract and expand at different rates than the cast iron block they may be bolted to, most modern day gaskets, bolts and heads require little to no maintenance after being installed.”
The key is using good quality gaskets and hardware. “New style gaskets do an excellent job of allowing the two surfaces to scrub on each other and still maintain a seal,” said Schropp. Using the professional guidance from Golen and Schropp, we recommend budget builders to plan on buying good quality gaskets and hardware with an aluminum cylinder head. Schropp also suggested “using an anode rod to try and prevent corrosion of the aluminum surfaces from the dissimilar metals if you are using an aluminum head and a cast iron block.”
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Combustion chamber design and volume are important in how the fuel is burnt.
Closed or Open Combustion Chamber?
These terms get thrown around casually without consideration for what they purpose is behind the design of these chambers. In respect to big block Chevy heads, these terms relate to the size of the combustion chamber. An open chamber will have a larger combustion chamber; typically the valves are not shrouded and the engine breathes better. An open chamber can be identified by the dome area of the chamber extending to the diameter of the cylinder bore.
A closed chamber typically has a diameter much smaller than the cylinder bore. The smaller combustion chamber results in the block’s deck surface extending into the combustion chamber area which forces the air/fuel mixture into the smaller combustion chamber when the piston is on the compression stroke.
When the piston nears the cylinder head and the flat area of the piston top and the flat area of the cylinder head get close, the air/fuel mixture is “squished” into the combustion chamber closer to the spark plug. This is where the term “squish area” comes from. The space between the flat area of the piston top and the cylinder head typically run cooler than the rest of the chamber and piston. This lower temperature is where the term “quench area” comes from.
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Semi-open combustion chamber heads can flow extremely well and provide the right mix of turbulence and "squish".
While the terms “quench” and “squish” are often used interchangeably by many manufacturers, quench and squish are
not the same thing, nor are they produced by the same set of conditions. The
Society of Automotive Engineers (SAE) has defined squish as the gases trapped between the piston dome and head that are ejected across the combustion chamber at high speed by the near-collision of the piston dome and head, causing turbulence and mixture homogenization. For our purposes, if the squish area is too close, there is a pumping loss and if the area is too far apart there will be lower squish velocity and less turbulence.
Quench on the other hand, is the ability to lower temperature of the end gases trapped between the piston dome and head by conduction. This prevents a second flame front from igniting the air/fuel mix prematurely. Members of the SAE acknowledge that for motors with 3.5” to 4.5” cylinder bores, a quench distance of 0.035” to 0.040” work well and result in near zero clearance due to thermal expansion, rod stretch and piston rock-over.
Properly designed quench areas have a dramatic effect on combustion quality and allow for higher compression ratios. For our budget friendly cylinder head guide, we can say in general terms, closed chambered heads can have an advantage in fuel efficiency and emissions by achieving a more complete burn, but valve shrouding can become an issue if the chamber is closed too much.
Combustion chamber size plays a significant role in compression (more is less and less is more). The smaller the combustion chamber, measured in cubic centimeters, the higher the compression will be.
Intake Port Shape and Size
It doesn’t take a lot of imagination to understand that a larger port has the potential to flow more than a smaller port. How much flow your engine needs will vary based on how much the engine can use. Port size is a very important issue when it comes to head design. Simply speaking in terms of flow, the smaller the port diameter, the less air potential there is.
Runner volume (length) is also very important. As the runner gets longer, movement in the column of air will increase the flow at lower RPMs and decrease the flow at higher RPMs.
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Intake port shape and size are important considerations in reaching your goal.
If you intend on doing a lot of low rpm street driving with a low-lift camshaft, performance will be less than optimal on cylinder heads with huge intake ports. The reverse is also true; high revving, big lift cammed engines with big displacement will not like smaller intake ports.
It’s true that a larger intake runner will allow more air and atomized fuel to flow through, but the larger area will also slow the velocity of the air and fuel flowing through it. Smaller runners speed up the flow, which improves throttle response and torque, but may not deliver the maximum amount of energy that your engine can use. The perfect combination of good flow and velocity is the challenge.
Common thought on port shapes is that oval shaped ports leave fewer opportunities for eddies and irregularities of flow in the corners because there are no corners, however, for budget friendly street heads running on pump gas, you should think of oval and rectangular ports as a function of size, not of shape.
RPMs are a big deal for street cars running on pump gas. Port shape is not as important as the cross sectional diameter and length of the runner matched to the RPMs. It’s highly unlikely that a street car is going to be spinning 7,000 RPM from stoplight to stoplight, thus a huge diameter, big volume oval port runner will probably under perform in the street RPM range.
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Runner volume can make or break a daily driver.
Exhaust port shape and runner volume is even less important than the intake side, however, scavenging all the exhaust gasses from the combustion chamber means that you can refill the combustion chamber with more fuel and air. More fuel and air means more power, so there is some consideration in the exhaust runner size and exhaust port shape. Our best advice is to call the manufacturer’s tech lines or talk to your engine builder for guidance on runner size.
Comprehensive Guide to BBC Cylinder Heads by Application
For our guide, we chose to break down the “budget friendly” BBC cylinder heads into categories that include the entry level and work up to the street/strip category and up to the dedicated performance car level. We also include a breakdown on why we think the cylinder heads represented in each category are the best fit for the application. The cylinder heads are not listed in order of preference, simply by the company’s name in alphabetic order. Where applicable, we have included additional information on engine size as big block Chevy’s covered in this article range from engines manufactured from 1965 through 2006.
Budget Big Block Chevy Cylinder Heads For Entry Level Street
Looking for an entry level set of heads for street use goes beyond price. Given that GM factory production heads commonly had runner volumes of 230 to 270 cc. Larger volume runners were used in GM’s performance versions. Aftermarket cylinder heads have improved airflow but must be matched to the camshaft, intake and exhaust systems for the optimal results. The heads listed below are good choices for an application that is intended to be higher performing than stock and still used on the street for daily driving.
Smaller ports and runners will keep the mixture of air/fuel at a higher velocity making driving from stop light to stop light and idle quality a lot more steady. With too large of a runner volume, a basic stock type engine will lug at low RPMs until it gets to cruising speed. Entry level heads are designed for engine where there are not too many high performance upgrades already installed and the engine will be running on mid to high octane pump gas. Optimal runner volume for these conditions is somewhere in the range of 270 cc to 290 cc.
Dart 308cc Big Block Chevy Heads, Rectangular Port
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Dart 308 cast iron cylinder head.
Perfect for: Entry Level Street or Street/Strip where front end weight is not an issue.
Material: Cast Iron Alloy
Cost: $1,700 per set
Intake Runner: 308cc
Combustion Chamber: Heart Shaped, 121 cc
- Additional Specs:
- Part Number: 15100111
- Intake Port Shape: Rectangular
- Intake Runner Volume: 308cc
- Exhaust Runner Volume: 129 cc
- Exhaust Port Shape: Round
- Intake Valve Diameter: 2.250″
- Intake Valve Angle: 24°
- Exhaust Valve Diameter: 1.880″
- Exhaust Valve Angle: 15°
- Maximum Valve Lift: 0.660″
- Springs Per Valve: Single
- Retainer Locks: 10°
- Valve Train: Standard BBC 7/16” Stud Mount
- Guideplates: Hardened Steel, 3/8″ Pushrod size
- Application: 396 ci Mark IV (1966-1970), 402 ci Mark IV (1970-1972), 427 ci Mark IV(1966-1969), 454 ci Mark IV (1970-1990), 454 ci Gen V (1991-1995), 454 ci Gen VI (1996-2000)
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Edelbrock E Street 290 aluminum cylinder head.
Edelbrock E Street 290 (#50459)
Perfect for: Entry Level Street or Street/Strip
Material: Aluminum
Cost: $1,725 per set
Intake Runner: 290 cc
Combustion Chamber: Proprietary Semi Open Style, 110 cc
- Additional Specs:
- Part Number: 50459
- Intake Port Shape: Oval
- Intake Runner Volume: 290 cc
- Exhaust Runner Volume: 110 cc
- Exhaust Port Shape: D-Port
- Intake Valve Diameter: 2.190″
- Intake Valve Angle: 26°
- Exhaust Valve Diameter: 1.880″
- Exhaust Valve Angle: 26°
- Maximum Valve Lift: 0.700″
- Springs Per Valve: Dual
- Retainer Locks: 10°
- Valve Train: Standard BBC 7/16” Stud Mount
- Guideplates: Hardened Steel, 3/8″ Pushrod size
- Application: 396 ci Mark IV (1965-1970), 402 ci Mark IV (1970-1972), 427 ci Mark IV(1963), 427 ci Mark IV(1966-1969), 454 ci Mark IV (1970-1990), 454 ci Gen V (1991-1995)
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Patriot Performance Freedom Series 2211 aluminum cylinder head.
Patriot Performance Freedom Series (#2211)
Perfect for: Entry Level Street or Street/Strip
Material: Aluminum
Cost: $1,400 per set
Intake Runner: 320 cc
Combustion Chamber: Proprietary, 119 cc
- Additional Specs:
- Part Number 2211
- Intake Port Shape: Rectangular
- Intake Runner Volume: 320 cc
- Exhaust Runner Volume: 125 cc
- Exhaust Port Shape: Round
- Intake Valve Diameter: 2.250″
- Intake Valve Angle: 24°
- Exhaust Valve Diameter: 1.880″
- Exhaust Valve Angle: 15°
- Maximum Valve Lift: 0.600″
- Springs Per Valve: hydraulic roller springs
- Retainer Locks: 7°
- Valve Train: Standard BBC 7/16” Stud Mount
- Guideplates: Hardened Steel, 3/8″ Pushrod size
- Priced around $1,400 per set
- Application: 396 ci Mark IV (1966-1970), 402 ci Mark IV (1970-1972), 427 ci Mark IV (1966-1969), 454 ci Mark IV (1970-1990), 454 ci Gen V (1991-1995), 454 ci Gen VI (1996-2000)
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Summit Racing cast iron cylinder head.
Summit Racing Cast Iron (#SUM-152125)
Perfect for: Entry Level Street or Street/Strip
Material: Cast Iron
Cost: $1,500 per set
Intake Runner: 308cc
Combustion Chamber: Heart shaped 119 cc
- Additional Specs:
- Part Number: SUM-152125
- Intake Port Shape: Rectangular
- Intake Runner Volume: 308cc
- Exhaust Runner Volume: 129 cc
- Exhaust Port Shape: Square
- Intake Valve Diameter: 2.250″
- Intake Valve Angle: 24°
- Exhaust Valve Diameter: 1.880″
- Exhaust Valve Angle: 15°
- Maximum Valve Lift: 0.660″
- Springs Per Valve: Single
- Retainer Locks: 10°
- Valve Train: Standard BBC 7/16” Stud Mount
- Guideplates: Hardened Steel, 3/8″ Pushrod size
- Application: 396 ci Mark IV (1965-1970), 402 ci Mark IV (1970-1972), 427 ci Mark IV (1966-1969), 454 ci Mark IV (1970-1990), 454 ci Gen V (1991-1995)
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Trick Flow Specialties PowerOval 280 aluminum cylinder heads.
Trick Flow Specialties PowerOval 280
Perfect for: Entry Level Street or Street/Strip
Material: Aluminum
Cost: $1,850 per set
Intake Runner: 280 cc
Combustion Chamber: Open Chamber 113 cc
- Additional Specs:
- Part Number: TFS-41300001 / TFS-41300002
- Intake Port Shape: Oval
- Exhaust Runner Volume: 137 cc
- Exhaust Port Shape: Round
- Intake Valve Diameter: 2.190″
- Intake Valve Angle: 24°
- Exhaust Valve Diameter: 1.880″
- Exhaust Valve Angle: 15°
- Maximum Valve Lift: 0.700″
- Springs Per Valve: Dual
- Retainer Locks: 10°
- Valve Train: Standard BBC 7/16” Stud Mount
- Guideplates: Hardened Steel, 3/8″ Pushrod size
- Application: 396 ci Mark IV (1966-1970), 402 ci Mark IV (1970-1972), 427 ci Mark IV (1966-1969), 454 ci Mark IV (1970-1990), 454 ci Gen V (1991-1995), 454 ci Gen VI (1996-2000)
World Products Merlin Oval Port Iron Heads
Perfect for: Entry Level Street or Street/Strip
Material: Cast Iron
Cost: $1,675 per set
Intake Runner: 269 cc
Combustion Chamber: Open Chamber 119 cc
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World Products Merlin Oval Port Iron Heads.
- Additional Specs:
- Part Number: 030040-1 (Hydraulic Flat Tappet)/ 030040-2 (Solid Flat Tappet and Hydraulic Roller)
- Intake Port Shape: Oval
- Exhaust Port Shape: Round
- Intake Valve Diameter: 2.300″
- Intake Valve Angle: 24°
- Exhaust Valve Diameter: 1.880″
- Exhaust Valve Angle: 15°
- Maximum Valve Lift: 0.600″
- Springs Per Valve: 030040-1: Single. 030040-2: Dual
- Retainer Locks: 7°
- Valve Train: Standard BBC 7/16” Stud Mount
- Guideplates: Hardened Steel, 3/8″ Pushrod size
- Application: 396 ci Mark IV (1966-1970), 402 ci Mark IV (1970-1972), 427 ci Mark IV (1966-1969), 454 ci Mark IV (1970-1990), 454 ci Gen V (1991-1995), 454 ci Gen VI (1996-2000)
Street Performance & Muscle Car
Typically a bigger valve, port size and runner volume are desired in higher performance applications, however, knowing that this guide is for budget friendly, pump gas, street cruisers, we were looking for runner volumes in the range of 290 cc to 320 cc. On the smaller cubic inch big blocks, it’s probably still wise to stay down in the 290 cc to 305 cc range for drivability.
454 cubic inch big blocks are considered small by today’s standards where 502 ci and 572 ci engines are becoming more common. Obviously, a 454 ci engine will not have the same airflow demands as a 572 ci engine. The cylinder heads listed below still have good drivability in stop-and-go driving situations and low speed response while giving improved performance at the top end.
Dart 345 cast iron cylinder heads
Perfect for: Street Performance
Material: Cast Iron
Cost: $1,800 per set
Intake Runner: 345 cc
Combustion Chamber: Heart Shaped 121 cc
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Dart 345 cast iron cylinder head.
- Additional Specs:
- Part Number: 15200132
- Intake Port Shape: Rectangular
- Exhaust Runner Volume: 129 cc
- Exhaust Port Shape: Round
- Intake Valve Diameter: 2.300″
- Intake Valve Angle: 24°
- Exhaust Valve Diameter: 1.880″
- Exhaust Valve Angle: 15°
- Maximum Valve Lift: 0.660″
- Springs Per Valve: Dual
- Retainer Locks: 10°
- Valve Train: Standard BBC 7/16” Stud Mount
- Guideplates: Hardened Steel, 3/8″ Pushrod size
- Application: 396 ci Mark IV (1966-1970), 402 ci Mark IV (1970-1972), 427 ci Mark IV(1966-1969), 454 ci Mark IV (1970-1990), 454 ci Gen V (1991-1995), 454 ci Gen VI (1996-2000)
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Edelbrock Performer 454-O aluminum cylinder head.
Edelbrock Performer 454-O
Perfect for: Street Performance
Material: Aluminum
Cost: $1,900 per set
Intake Runner: 290 cc
Combustion Chamber: Proprietary Semi Open Style 110 cc
- Additional Specs:
- Part Number: 60479
- Intake Port Shape: Oval
- Exhaust Runner Volume: 110 cc
- Exhaust Port Shape: Square
- Intake Valve Diameter: 2.190″
- Intake Valve Angle: 26°
- Exhaust Valve Diameter: 1.880″
- Exhaust Valve Angle: 26°
- Maximum Valve Lift: 0.700″
- Springs Per Valve: Single
- Retainer Locks: 7°
- Valve Train: Standard BBC 7/16” Stud Mount
- Guideplates: Hardened Steel, 3/8″ Pushrod size
- Application: 396 ci Mark IV (1966-1970), 402 ci Mark IV (1970-1972), 427 ci Mark IV (1966-1969), 454 ci Mark IV (1970-1990), 454 ci Gen V (1991-1995), 454 ci Gen VI (1996-2000)
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Patriot Performance Freedom Series 2214 aluminum cylinder heads.
Patriot Performance Freedom Series (#2214)
Perfect for: Street Performance
Material: Aluminum
Cost: $1,600 per set
Intake Runner: 320 cc
Combustion Chamber: Proprietary 119 cc
- Additional Specs:
- Part Number: 2214
- Intake Port Shape: Rectangular
- Exhaust Runner Volume: 125 cc
- Exhaust Port Shape: Round
- Intake Valve Diameter: 2.250″
- Intake Valve Angle: 24°
- Exhaust Valve Diameter: 1.880″
- Exhaust Valve Angle: 15°
- Maximum Valve Lift: 0.700″
- Springs Per Valve: dual
- Retainer Locks: 10°
- Valve Train: Standard BBC 7/16” Stud Mount
- Guideplates: Hardened Steel, 3/8″ Pushrod size
- Application: 396 ci Mark IV (1966-1970), 402 ci Mark IV (1970-1972), 427 ci Mark IV (1966-1969), 454 ci Mark IV (1970-1990), 454 ci Gen V (1991-1995), 454 ci Gen VI (1996-2000)
RHS Pro Action 320 cc Hydraulic Roller
Perfect for: Street Performance
Material: Cast Iron
Cost: $1,575 per set
Intake Runner: 320 cc
Combustion Chamber: Proprietary Modified 119 cc
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RHS Pro Action 320 Hydraulic Roller cast iron cylinder head.
- Additional Specs:
- Part Number: 11301-02
- Intake Port Shape: Rectangular
- Exhaust Runner Volume: 135 cc
- Exhaust Port Shape: Rectangular
- Intake Valve Diameter: 2.250″
- Intake Valve Angle: 24°
- Exhaust Valve Diameter: 1.880″
- Exhaust Valve Angle: 15°
- Maximum Valve Lift: 0.600″
- Springs Per Valve: Dual
- Retainer Locks: 10°
- Valve Train: Standard BBC 7/16” Stud Mount
- Guideplates: Hardened Steel, 3/8″ Pushrod size
- Application: 396 ci Mark IV (1965-1970), 402 ci Mark IV (1970-1972), 427 ci Mark IV(1966-1969), 454 ci Mark IV (1970-1990), 454 ci Gen V (1991-1995), 454 ci Gen VI (1996-2000)
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World Products Merlin Rectangular Port Iron Heads.
World Products Merlin Rectangular Port Iron Heads
Perfect for: Street Performance
Material: Cast Iron
Cost: $1,675
Intake Runner: 320 cc
Combustion Chamber: Open Chamber 119 cc
- Additional Specs:
- Part Number: 030620-2 (Solid Flat Tappet & Hydraulic Roller)/ 030620-3 (Solid Roller)
- Intake Port Shape: Rectangular
- Exhaust Port Shape: Round
- Intake Valve Diameter: 2.300″
- Intake Valve Angle: 24°
- Exhaust Valve Diameter: 1.880″
- Exhaust Valve Angle: 15°
- Maximum Valve Lift: 030620-2: 0.650″ / 030620-3: 0.700″
- Springs Per Valve: Dual
- Retainer Locks: 10°
- Valve Train: Standard BBC 7/16” Stud Mount
- Guideplates: Hardened Steel, 3/8″ Pushrod size
- Application: 396 ci Mark IV (1966-1970), 402 ci Mark IV (1970-1972), 427 ci Mark IV (1966-1969), 454 ci Mark IV (1970-1990), 454 ci Gen V (1991-1995), 454 ci Gen VI (1996-2000)
Wild Street and Dedicated Performance
For an application where performance is desired over streetability comfort. The heads listed below are for larger cubic inch big blocks where the airflow demands are greater or highway driving where the engine does not have to lumber through the gears to get to cruising speed often. Once you get to cruising speed however, these heads should provide all the flow you need or want.
Cylinder heads in the dedicated performance category will do well with intake and exhaust upgrades that maximize the flow characteristics. Large port openings and runner volumes along with larger valves and valve train set up for higher lift are the standards of a wild street or dedicated performance head.
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Edelbrock High Compression 454-O aluminum cylinder head.
Edelbrock High Compression 454-O (#60499) 50 state legal
Perfect for: Wild Street Performance or Dedicated Performance
Material: Aluminum
Cost: $1,900 per set
Intake Runner: 290 cc
Combustion Chamber: Proprietary Semi Open Style 100 cc
- Additional Specs:
- Part Number: 60499
- Intake Port Shape: Oval
- Exhaust Runner Volume: 110 cc
- Exhaust Port Shape: Square
- Intake Valve Diameter: 2.190″
- Intake Valve Angle: 26°
- Exhaust Valve Diameter: 1.880″
- Exhaust Valve Angle: 26°
- Maximum Valve Lift: 0.700″
- Springs Per Valve: Single
- Retainer Locks: 7°
- Valve Train: Standard BBC 7/16” Stud Mount
- Guideplates: Hardened Steel, 3/8″ Pushrod size
- Application: 396 ci Mark IV (1966-1970), 402 ci Mark IV (1970-1972), 427 ci Mark IV (1966-1969), 454 ci Mark IV (1970-1990), 454 ci Gen V (1991-1995), 454 ci Gen VI (1996-2000)
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Trick Flow Specialties PowerPort 320 aluminum cylinder heads.
Trick Flow Specialties PowerPort 320
Perfect for: Wild Street Performance or Dedicated Performance
Material: Aluminum
Cost: $1,950 per set
Intake Runner: 320 cc
Combustion Chamber: Open Chamber 122 cc
- Additional Specs:
- Part Number: TFS-41400001 or TFS-41400002
- Intake Port Shape: Rectangular
- Exhaust Runner Volume: 137 cc
- Exhaust Port Shape: Round
- Intake Valve Diameter: 2.250″
- Intake Valve Angle: 24°
- Exhaust Valve Diameter: 1.880″
- Exhaust Valve Angle: 15°
- Maximum Valve Lift: 0.700″
- Springs Per Valve: Dual
- Retainer Locks: 10°
- Valve Train: Standard BBC 7/16” Stud Mount
- Guideplates: Hardened Steel, 3/8″ Pushrod size
- Application: 396 ci Mark IV (1966-1970), 402 ci Mark IV (1970-1972), 427 ci Mark IV (1966-1969), 454 ci Mark IV (1970-1990), 454 ci Gen V (1991-1995), 454 ci Gen VI (1996-2000)
Patriot Performance Freedom Series (#2216)
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Patriot Performance Freedom Series 2216 aluminum cylinder heads.
Perfect for: Wild Street Performance or Dedicated Performance
Material: Aluminum
Cost: $1,900 per set
Intake Runner: 320 cc
Combustion Chamber: Proprietary 119 cc
- Additional Specs:
- Intake Port Shape: Rectangular
- Exhaust Runner Volume: 125 cc
- Exhaust Port Shape: Round
- Intake Valve Diameter: 2.300″
- Intake Valve Angle: 24°
- Exhaust Valve Diameter: 1.880″
- Exhaust Valve Angle: 15°
- Maximum Valve Lift: 0.800″
- Springs Per Valve: Triple
- Retainer Locks: 10°
- Valve Train: Standard BBC 7/16” Stud Mount
- Guideplates: Hardened Steel, 3/8″ Pushrod size
- Application: 396 ci Mark IV (1966-1970), 402 ci Mark IV (1970-1972), 427 ci Mark IV (1966-1969), 454 ci Mark IV (1970-1990), 454 ci Gen V (1991-1995), 454 ci Gen VI (1996-2000)
RHS Pro Action 320 cc Solid Roller
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RHS Pro Action 320 cc Solid Roller cast iron cylinder head.
Perfect for: Wild Street Performance or Dedicated Performance
Material: Aluminum
Cost: $1,780 per set
Intake Runner: 320 cc
Combustion Chamber: Proprietary 119 cc
- Additional Specs:
- Intake Port Shape: Rectangular
- Exhaust Runner Volume: 135 cc
- Exhaust Port Shape: Rectangular
- Intake Valve Diameter: 2.250″
- Intake Valve Angle: 24°
- Exhaust Valve Diameter: 1.880″
- Exhaust Valve Angle: 15°
- Maximum Valve Lift: 0.750″
- Springs Per Valve: Dual
- Retainer Locks: 10°
- Valve Train: Standard BBC 7/16” Stud Mount
- Guideplates: Hardened Steel, 3/8″ Pushrod size
- Application: 396 ci Mark IV (1965-1970), 402 ci Mark IV (1970-1972), 427 ci Mark IV(1966-1969), 454 ci Mark IV (1970-1990), 454 ci Gen V (1991-1995), 454 ci Gen VI (1996-2000)
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RHS Pro Action 360 cc Solid Roller cast iron cylinder head.
RHS Pro Action 360 cc
Perfect for: Wild Street Performance or Dedicated Performance
Material: Cast Iron
Cost: $1,780 per set
Intake Runner: 360 cc
Combustion Chamber: Proprietary 119 cc
- Additional Specs:
- Part Number: 11302-02 (Hydraulic Roller)or 11302-03 (Solid Roller)
- Intake Port Shape: Rectangular
- Exhaust Runner Volume: 135 cc
- Exhaust Port Shape: Rectangular
- Intake Valve Diameter: 2.300″
- Intake Valve Angle: 24°
- Exhaust Valve Diameter: 1.880″
- Exhaust Valve Angle: 15°
- Maximum Valve Lift: 0.600″ (11302-02) / 0.750″ (11302-03)
- Springs Per Valve: Dual
- Retainer Locks: 10°
- Valve Train: Standard BBC 7/16” Stud Mount
- Guideplates: Hardened Steel, 3/8″ Pushrod size
- Application: 396 ci Mark IV (1965-1970), 402 ci Mark IV (1970-1972), 427 ci Mark IV(1966-1969), 454 ci Mark IV (1970-1990), 454 ci Gen V (1991-1995), 454 ci Gen VI (1996-2000)
The Final Word
It’s been said that the terms “budget” and “big block” don’t go together and qualify as an oxymoron when used together. However, the cylinder heads listed in our guide above are well within the range of what can be considered budget friendly. Nan Gelhard of Summit Racing Equipment emphasized that point by saying; “When you talk about dollars per horsepower you can see how it changes as you go from street to strip.”
Whether you have a stock big block that you salvaged from the wrecking yard and are looking for some modern technology heads to bolt on, or if you want to beef up your daily driver to take it to the drag strip occasionally, we’ve got you covered in one of the budget friendly categories listed above.
Billy Mitchell Jr. from World Products encourages enthusiasts to call the tech lines or work with your engine builder. “It’s important to marry the runner size and port shape to the cubic inch size of the engine,” says Mitchell. Chad Bowling of Patriot Performance also recommended working with your engine builder on the engine internals like camshaft before picking a set of assembled heads, “Most aftermarket head manufacturers offer cylinder heads in a variety of spring packages from hydraulic flat tappet to solid roller,” Bowling states. The final word is that it is OK to use this guide as you would any other guide, as a means of gathering information to talk with your engine builder about the best method of achieving your goals.
http://www.superchevy.com/how-to/project-cars/sucp-1208-big-block-heads-shootout-the-o-vs-r/
Sources
Dart Machinery
Phone: 248-362-1188
Edelbrock
Phone: 310-781-2222
Patriot Performance
Phone: 888-462-8276 FREE
RHS
Phone: 877-776-4323 FREE
Summit Racing
Phone: 330-630-0240
Trick Flow Specialties
Phone: 330-630-1555
World Products
Phone: 631-981-1918
http://www.jegs.com/p/Chevrolet-Per...w-Tie-Aluminum-Cylinder-Heads/761642/10002/-1
http://www.superchevy.com/how-to/project-cars/sucp-1208-big-block-heads-shootout-the-o-vs-r/
Big-Block Heads Shootout - The Big O Vs. The Big R
Oval ports and rectangular port heads
Richard Holdener Jul 18, 2012
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Two issues back, we subjected a 468-inch big-block Chevy to a variety of different oval-port cylinder heads, ranging from stock peanut-port-style heads to full CNC-ported versions (see “The Big O”). In that story, we attempted to dispel the myth that any powerful big-block combination must include rectangular-port cylinder heads. Equipped with the right oval-port heads, the 468 easily exceeded 600 hp on the engine dyno. Most of the oval-port heads tested in part 1 offered airflow that would support another 100 hp on the right combination.
Contrary to popular opinion, our combination was limiting the potential of the oval-port cylinder heads, not the other way around. It is true that all of the factory performance big-blocks sported rectangular-port heads back in the day, but much has changed since the first muscle car era. Not only does a good set of aftermarket oval-port heads outflow the factory rec-port stuff, it does so with reduced port volume. Big, lazy ports are ideally suited for neither performance nor street use, while smaller, efficient ports offer the best of both worlds. Nowhere was this more evident than in the fact that a couple of manufacturers chose to supply oval-port heads once again on this larger (and more powerful) 496 test engine.
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A common stroker displacement, our 496 was the result of combining a 0.060-inch overbore with a 4.25-inch stroker crank. Our BBC rotating assembly came from the experts at Scat Enterprises. The BBC combination featured a 4340 forged steel crank combined with a set of matching 6.385-inch, I-beam rods. We chose a Scat crankshaft design specifically for our late-model, one-piece, four-bolt, Gen-6 block. The Scat crank and rods were combined with a set of forged pistons from JE. Offered as part of their SRP line up, the JE Pistons featured 18cc domes to produce a static compression ratio of 10.0:1 with typical 120cc combustion chambers.
The short-block was built not to maximize power production, but rather to demonstrate what is possible for street use in a performance driver. We wanted all of our testing to be run on pump gas, so we kept the static compression at a reasonable level. L&R Automotive was responsible for machining and balancing of the combination, while Total Seal came through with a set of performance rings to ensure proper sealing.
The displacement ensured that our 496 would be more powerful than the 468 used in part 1, but we hedged our bets with the installation of a wilder cam profile as well. Balancing the street/performance theme, we chose a small solid roller profile from Comp Cams. The 300BR-14 offered 0.652 lift, a 255/262 duration split and 114-degree LSA. To work in the Gen-6 block, the cam was teamed with a set of 0.300-tall solid roller lifters and a double roller timing chain.
Since the cam and timing chain were designed for a Gen-4 block, it was necessary to eliminate the factory cam retaining plate in favor of a traditional cam button. The swap also required the use of a custom front cover (PN217) from Comp Cams to provide the necessary room for the double-roller chain (factory Gen-6 covers must be run with a single-roller chain).
Finishing touches on the test mill included an Edelbrock Victor Jr. 454-R intake, a Holley 950 HP carb and SFI-approved, neutral damper from Procomp Electronics.
Prior to running the test engine, all of the heads were treated to flow bench testing to correlate the flow potential to the power gains. In truth, heads like the Brodix BB-3 Xtra O offered over 400 cfm--enough to support more than 800 hp. We were just scratching the surface or their potential with our 496 street/strip combination. After bench testing, we subjected the heads to port and chamber volume measurements. Since the compression ration is a function of the chamber volume, chamber size has a significant effect on the power curve (to the tune of 3-4 percent per point). Measurements indicated that our test heads varied greatly, from a low of 107cc to a high of 123cc. Bear this in mind when viewing the power numbers.
It is again worth mentioning that though this was originally to be a rec-port-only head test (to follow the oval-ports tested in part 1), some of the manufacturers supplied oval-port heads for this 496. Don't look down you noses at oval-port heads, as testing from both stories suggests that if anything, oval is the new square.
Test 1: Stock GM 088 Iron
Prior to running any of the aftermarket heads we had to establish a baseline by running the stockers. We chose a set of 088 castings that featured 316cc intake ports, 121cc exhaust ports and 123cc combustion chambers. The airflow data suggested that the stock iron heads would support over 650 hp, but on this 496, the heads managed to produce peak numbers of 630 hp at 6,600 rpm and 577 lb-ft of torque at 5,300 rpm. While 630 hp would make a serious street motor, we would see that the right head choice on this application would add nearly 100 hp to that total.
- GM rectangular port castings
- Retail Price-NA
- Intake Valve Size-2.19
- Exhaust Valve Size-1.88
- Intake Port Vol-316 cc
- Exhaust Port-121 cc
- Chamber Volume-123 cc
- Peak Power- 630 @ 6,600 rpm
- Peak Torque- 577 lb-ft @ 5,300 rpm
- Avg HP (3,500-6,500)-532.4
- Avg TQ (3,500-6,500)- 560.5 lb-
- TQ @ 4,000 RPM - 562.7lb-ft
Flow Data: CFM @ 28-ins
Stock 088
Lift In Ex
0.050 32 27
0.100 77 56
0.200 144 112
0.300 206 142
0.400 245 166
0.500 289 188
0.600 320 192
0.700 334 197
0.800 335 201
Test 2: Summit Racing Iron
Many would dismiss the iron heads simply for the weight savings, but don't count them out, especially when you consider the price and performance. These rectangular port iron heads from Summit Racing offered surprising bang for the buck. The Summit Racing head upgrade improved the power output of the 496 from 630 hp and 577 lb-ft to 688 hp and 607 lb-ft. This was all the more impressive considering the fact that the heads cost just $750 bucks each, assembled. Toss in the fact that the Summit heads flow only marginally better than the stock heads and share the same combustion chamber volume. If you are looking for iron heads on a budget, look no further than Summit Racing.
- Retail Price-$749
- Intake Valve Size-2.25
- Exhaust Valve Size-1.88
- Intake Port Vol-309 cc
- Exhaust Port Vol-127 cc
- Chamber Volume-122 cc
- Peak Power- 688 hp @ 6,600 rpm
- Peak Torque- 607 lb-ft @ 5,400 rpm
- Ave HP (3,500-6,500)-555.5
- Ave TQ (3,500-6,500)-582.1
- TQ @ 4,000 RPM-563.3 lb-ft
Summit Racing Iron
Flow Data: CFM @ 28-ins
Lift In Ex
.050 34 34
.100 69 69
.200 146 109
.300 204 155
.400 264 192
.500 309 223
.600 340 246
.700 323 262
.800 330 273
Test 3: Procomp Electronics Rec-Port CNC
The aluminum heads from Procomp Electronics combined the largest port volume and (nearly) peak flow numbers with the lowest retail cost. The intake port volume measured a sizable 369cc, while the exhaust checked in at 157cc. This head configuration would be much more at home on a larger displacement, higher horsepower application, but how can you argue with aluminum BBC heads that flowed over 400 cfm for around $600? Equipped with the Procomp heads, the BBC stroker pumped out 690 hp and 600 lb-ft of torque. We suspect the large port volume and sizable combustion chamber hurt torque and power on this application, as many of the other heads featured smaller chambers and port volumes. We'd like to see this head strut its stuff on a high-compression 572, but for our 496, it was likely just too big.
- Retail Price-$625
- Intake Valve Size-2.30
- Exhaust Valve Size-1.88
- Intake Port Vol-369 cc
- Exhaust Port Vol-157 cc
- Chamber Volume-123 cc
- Peak Power- 690 hp @ 6,300 rpm
- Peak Torque- 600 lb-ft @ 5,500 rpm
- Ave HP (3,500-6,500)-554.2 hp
- Ave TQ (3,500-6,500)- 581 lb-ft
- Tq @ 4,000 RPM-568.3 lb-ft
Procomp Electronics BBC Rec-Port CNC
Flow Data: CFM @ 28-ins
Lift In Ex
.050 35 31
.100 70 67
.200 152 132
.300 234 175
.400 294 206
.500 336 231
.600 364 251
.700 389 267
.800 403 279
Test 4: Trick Flow Specialties PowerPort 360 Heads
Like the Procomp heads, the PowerPort 360s from Trick Flow Specialties were probably a tad on the big side for the 496. With intake ports that measured 357cc, the impressive PowerPorts would be more at home on a big-block exceeding 500 cubic inches. With peak intake flow numbers of 384 cfm, the heads we capable of supporting over 750 hp, but on our 496 manage 691 hp and 603 lb-ft of torque. The PowerPort heads shared the large (122cc) combustion chamber volume of the stock heads and came in at a cost-effective $1,229 (through Summit Racing).
- Retail Price-$1229
- Intake Valve Size-2.30
- Exhaust Valve Size-1.88
- Intake Port Vol-357 cc
- Exhaust Port Vol-134 cc
- Chamber Volume-122 cc
- Peak Power- 691 hp @ 6,400 rpm
- Peak Torque- 603 lb-ft @ 5,400 rpm
- Ave HP (3,500-6,500)-555.3
- Ave TQ (3,500-6,500)- 581.9 lb-ft
- TQ @ 4,000 RPM-562.3 lb-ft
Trick Flow Specialties PowerPort 360 head
Flow Data: CFM @ 28-ins
Lift In Ex
.050 35 30
.100 72 61
.200 148 125
.300 217 168
.400 275 198
.500 325 227
.600 360 246
.700 376 261
.800 384 273
Test 5: Brodix BB-3 Xtra 332
The new Brodix BB-3 Xtra 332 heads were not quite a rec-port head nor were they a conventional oval (or peanut) port head. They were somewhere in the middle, more like a rectangular-port with rounded corners. In truth, use of the 454-R (rec-port) intake may have hindered the power potential of the Brodix heads more than others due to the port mismatch. One thing for certain is that the Brodix heads topped all comers in terms of airflow with peak numbers of 409 cfm. Capable of supporting over 800 hp, our 496 produced 705 hp and 624 lb-ft of torque. We would love to port-match an intake to these heads in an attempt to translate all that airflow potential into power.
- Retail Price-$1840
- Intake Valve Size-2.30
- Exhaust Valve Size-1.88
- Intake Port Vol-335 cc
- Exhaust Port Vol-133 cc
- Chamber Volume-115 cc
- Peak Power- 705 hp @ 6,400 rpm
- Peak Torque- 624 lb-ft @ 5,200 rpm
- Ave HP (3,500-6,500)-574.6
- Ave TQ (3,500-6,500)- 602.7 lb-ft
- TQ @ 4,000 RPM-585.7 lb-ft
Brodix BB-3 Xtra 33
Flow Data: CFM @ 28-ins
Lift In Ex
.050 33 31
.100 66 69
.200 147 120
.300 211 173
.400 273 221
.500 333 256
.600 380 277
.700 409 286
.800 403 296
Test 6: Dart Pro 1 335
The Pro 1 name from Dart has always meant power and this test illustrates that the name still carries some weight. For our street/strip 496 BBC, Dart supplied a set of its CNC-ported 335 heads. With flow numbers that reached nearly 400 cfm, the Dart Pro 1s were another set of 800-hp heads in search of a motor. The Dart Pro 1 heads featured rolled valve angles and raised exhaust ports to improve flow and power, but remained compatible with stock accessories. Run on the dyno, the big-block produced 717 hp and 619 lb-ft of torque. Equipped with a smaller chamber shared by the AFR and Edelbrock heads, the Dart would likely be right in the hunt for maximum power.
- Retail Price-$2021
- Intake Valve Size-2.30
- Exhaust Valve Size-1.88
- Intake Port Vol-303 cc
- Exhaust Port Vol-137 cc
- Chamber Volume-122 cc
- Peak Power- 717 hp @ 6,500 rpm
- Peak Torque- 619 lb-ft @ 5,600 rpm
- Ave HP (3,500-6,500)-568.0
- Ave TQ (3,500-6,500)-594.3 lb-ft
- TQ @ 4,000 RPM-572.5 lb-ft
Dart Pro 1 335
Flow Data: CFM @ 28-ins
Lift In Ex
.050 34 29
.100 69 61
.200 148 125
.300 228 181
.400 294 219
.500 336 249
.600 376 271
.700 398 281
.800 399 289
Test 7: Edelbrock E-CNC 355
Edelbrock has stepped up in a big way recently with new performance offerings and these E-CNC 335 heads are a perfect example. Proudly made in the USA, the E-CNC heads offered plenty of flow, peaking at 391 cfm on the intake and 285 cfm on the exhaust. Sporting the smallest combustion chamber of the bunch at 107cc, the Edelbrock heads produced the highest static compression ratio. Naturally this helped power, allowing the E-CNC heads to produce 723 hp and 627 lb-ft of torque.
- Retail Price-$1,630 (required spring upgrade)
- Intake Valve Size-2.30
- Exhaust Valve Size-1.88
- Intake Port Vol-353cc
- Chamber Volume-107 cc
- Exhaust Port Vol-135 cc
- Peak Power- 723 hp @ 6,500 rpm
- Peak Torque- 627 lb-ft @ 5,600 rpm
- Ave HP (3,500-6,500)-573.5 hp
- Ave TQ (3,500-6,500)- 599.9 lb-ft
- TQ @ 4,000 RPM-574.0 lb-ft
Edelbrock E-CNC 355
Flow Data: CFM @ 28-ins
Lift In Ex
.050 33 29
.100 73 61
.200 148 132
.300 224 185
.400 283 226
.500 334 252
.600 364 270
.700 385 278
.800 381 285
Test 8 AFR Magnum 300 Oval
It takes more than just big flow numbers to make power, and these Airflow Research heads proved that. In fact, when asked to supply rec-port heads for this test, they opted to instead send over a set of oval-port heads. It new 300cc Magnum heads did not offer the highest peak flow numbers, topping out at 383 cfm (at .650 lift), but when combined with exceptional mid-lift flow and an efficient chamber design, the results were enough impressive. Power production is all about the combination of components working together and on this 496, the AFR Magnum 300 heads proved to be the optimum combination by producing 729 hp and 639 lb-ft of torque.
- Retail Price-$1,559
- Intake Valve Size-2.30
- Exhaust Valve Size-1.88
- Intake Port Vol-300 cc
- Exhaust Port Vol-123 cc
- Chamber Volume-110 cc
- Peak Power- 729 hp @ 6,500 rpm
- Peak Torque- 639 lb-ft @ 5,400 rpm
- Avg HP (3,500-6,500)-584.1
- Avg TQ (3,500-6,500)-611.4 lb-ft
- TQ @ 4,000 rpm-587.0 lb-ft
AFR Magnum 300 Oval
Flow Data: CFM @ 28-ins
Lift In Ex
.050 34 32
.100 74 62
.200 153 126
.300 233 198
.400 296 237
.500 345 263
.600 377 277
.700 371 288
.800 365 296
38/38
21 The combustion chamber of each cylinder head tested was measured.