Big-Block Chevy OE And Aftermarket Block Variants

Grumpy

The Grumpy Grease Monkey mechanical engineer.
Staff member
Generation Gap: Big-Block Chevy OE And Aftermarket Block Variants


By GREG ACOSTA AUGUST 07, 2018

When it comes to big-block engines, there are quite a few variants across multiple manufacturers. However, when you hear the words “big block” with no other qualifier, there is one engine that comes to mind more than others, and that is the big-block Chevrolet.

The big-block Chevy – or BBC, as it’s colloquially known – is arguably the most popular big-block engine on the market. It has some serious legs, with a production lifespan totaling 51 years. If you include aftermarket applications which have continued on past the end of Chevrolet’s official production, the big-block Chevy engine is a spry 60-years-old and counting.

In those 51 years of production, there were a total of seven different variants of the engine’s design. Luckily, for the sake of simplicity, the first three of those variants were short lived, and rarely come up in the performance aftermarket discussion. For the sake of thoroughness, those three early variants were the aptly named “Mark I” (or W-engine), the Mark II (or “Mystery Motor”), and the aborted Mark III project.

When it comes to the bulk of the aftermarket, the big-block Chevy came into its own with the Mark IV variant, and that’s where this story starts, especially when talking about aftermarket engine blocks.


World Products’ Merlin IV engine block is the latest evolution of its aftermarket big-block Chevy block. With the current tooling setup, both Mark IV and Gen V/VI architecture blocks come from the same raw casting, with only machining processes being different.
Starting at Four

The Mark IV big-block Chevy began life in 1965 and was produced until 1990. In that time it was manufactured in a variety of displacements and capabilities, while powering some of the most iconic muscle cars of the era. In fact, it could be said that the big-block Chevy helped define the genre.

The Mark IV incorporated a more traditional wedge-style combustion chamber, and revised valve angles, which differed considerably from the original W-engine design. The Mark IV’s more traditional design led to a large increase in efficiency – and power – solidifying it as a performance engine in the history books. “The Mark IV is certainly the most versatile of the generations, because in OE form there were numerous performance variants made,” says Jack McInnis of World Products. “Parts are mostly interchangeable and tuning options for them are abundant.”

New Generation, New Name

The next generation of the big-block Chevy engine was known as the Generation V, keeping the numerical sequence alive, but transitioning from the “Mark” nomenclature to “Generation” or “Gen,” presumably due to the fact that Ford was manufacturing the Mark VII and Mark VIII under the Lincoln brand. A seemingly innocuous little fact, but it’s an important differentiation that comes up when discussing the big-block Chevy.

The Generation V big-block debuted in 1991 with considerable changes. A one-piece rear-main seal, revised oiling system passages, and the removal of a the mechanical fuel pump were the major revisions to the engine block, along with all factory-produced big-block engine blocks coming equipped with four-bolt main caps

Oftentimes, the Generation V and Generation VI will be lumped together when referring to engine blocks. That’s because the engine blocks of the Gen V/VI, as it’s often referred to, were the same, with the changes between those two generations occurring outside of the block.

“The Gen V/VI could theoretically be the equal of the Mark IV, but factory performance was not part of the plan,” McInnis explains of the factory offerings. “Parts interchangeability with the Mark IV [and the Gen V/VI blocks] has its limitations,” he says of why the Mark IV architecture still reigns supreme in the aftermarket.

On the left is a "traditional" Mark IV architecture big-block crate engine, and on the right is an 8.1L big-block. Notice externally, there aren't a whole lot of visual indicators. The stands on the valve covers for coil packs, and counting head bolts would both help identification.

It’s All Sevens and Eights

The Generation VII big-block is known by several other names as well – the “L18,” “8.1L” or “Vortec 8100,” mainly. Introduced in the 2001 model-year, there were a large number of significant changes in the Gen VII engine, including a new firing order, new head bolt pattern (along with a totally new cylinder head), and an electronic fuel injection system that closely mirrored that found on Gen III engines.

“The Vortec 8100 was built for trucks, motor homes, industrial use and boats, and in OE form is the least performance-oriented of the three main platforms,” shares McInnis. “There were no factory performance options and tuning required some fairly serious hacking skills.” The 8.1L big-block only lasted until 2009, and when the last L18 rolled off the production line, it marked the end of the factory-produced big-block Chevrolet.

Intergenerational Hand Me Downs

With all the different generations, parts interchangeability between them can be confusing. “The Mark IV and the Gen V/VI have a degree of parts interchangeability, but it is limited,” McInnis offers. “Probably the most significant difference is that the Gen V/VI is designed with a one-piece rear seal. This means that the main cap, oil pump, oil pan, crankshaft and flywheel are unique to that engine.”

Moving to the top of the block, while the bolt pattern between the Mark IV and Gen V/VI cylinder heads are the same, swapping heads isn’t as simple a task as that might make it appear. “The cylinder heads are interchangeable, although cooling passages in the deck, particularly on early Gen V OE blocks, can cause sealing problems with Mark IV heads. The head gaskets are even different between the two,” says McInnis.

Notice the 8.1 is conspicuously absent from the interchangeability discussion. That’s not an oversight. “The 8.1 has almost no interchangeability with the other two,” McInnis says, flatly. “The 8.1 represents the last of the big blocks, and the factory changed a lot of things from the previous versions. If the 8.1 had been the first design back in 1965 and the aftermarket had developed a vast array of performance components for it, things might be different.” With the different head bolt pattern, different oil pan pattern, and a switch to largely metric thread throughout the engine, the Gen VII big-block Chevy is practically its own animal.

These two blocks are World's current big-block offerings. On the left is the Merlin IV, and on the right is the 8.1L replacement block. While you may notice additional head bolt holes on the Merlin, those are for various race heads on the market, and not for the L18's altered bolt pattern.

The Magic of Merlin

Now that we’ve discussed the three major generations of big-block Chevrolet blocks, we can effectively look at World Products’ aftermarket offerings, which cover Mark IV, Gen V/VI, and the 8.1L variants. “All three types, as produced by World, have significant upgrades over the OEM blocks,” says McInnis. “However, their capabilities are still skewed in the same order as the OEM blocks are, just at a higher level. That is, mostly dictated by the availability of (or lack thereof) performance parts for the respective engine types.”

World has been producing its line of aftermarket blocks for over 25 years, and is constantly improving the lineup, as noted by the fact that current production of the Merlin line of big-block Chevy engine blocks is dubbed the “Merlin IV.” “World has made continuous improvements to the Merlin big-block, with the newest iteration being the Merlin IV. When we made new foundry tooling for the new Merlin IV, we designed it so that all three types of block castings could be produced with the same tools,” McInnis explains.


One of the largest differences between the Mark IV and Gen V/VI block is the one-piece and two-piece rear main seal.

While there are still three distinct versions of the block, World is able to use the same casting for the Mark IV and Gen V/VI blocks. “The Gen V/VI style block uses the same casting [as the Gen IV variant] with some changes in the machining. World’s Gen V/VI block is machined to accept the Gen VI-style one-piece rear seal, timing cover, and oil pan,” says McInnis. “It does have a Mark IV style oil filter pad and fuel pump boss, as well as Siamesed cylinders and splayed 4-bolt main caps.”

The Merlin IV block comes in 21 separate configurations, covering every OEM Mark IV and Gen V/VI applications, along with several configurations designed purely for aftermarket performance.

All of the Merlin blocks are made from high-density cast iron, and are designed to handle huge power. Available deck heights for the .600-inch thick deck range from 9.500-inch up to 10.250-inch, with a maximum bore size of 4.625 inches. At the maximum bore size, the cylinder wall thickness is approximately .290 inches thick (with additional thickness on the thrust side), making for a robust platform, even bored all the way out.

The Merlin IV has traditional-pattern 7/16-inch blind-tapped head bolt holes, along with an additional row of bosses in the valley area for several race heads that utilize the additional bolt holes. The blocks have two options when it comes to the main caps: standard four-bolt nodular-iron versions, or the more robust splayed-four-bolt billet steel caps. The Merlin IV comes with a 2.120-inch cam bore standard, with an option for a 55mm cam bore.


All of the Merlin-series engine blocks come with four-bolt mains standard. Here, you can see the standard nodular-iron main caps, while billet steel main caps, with splayed outer bolts are available as an upgrade and recommended for severe-duty applications, or anything making over 1,000 horsepower.

Internally, the water jackets have been expanded for enhanced cooling capability. The Merlin IV has a priority main oiling system with the block set up for a standard-style oil pump, but with provisions for a relatively-easy conversion to a dry-sump system, if that’s how you roll. The spin-on oil filter location has been revised to clear a kickout-style oilpan, and is dual-drilled to accept stock-style and aftermarket oil pans.

For the 8.1L big-block Chevy, World offers three part numbers for the cast-iron upgraded block, which doesn’t fall under the “Merlin” banner, but incorporates a number of the same upgrades, but in the late-model architecture. Available in three bore sizes — 4.245, 4.495, and 4.595 inches — the max bore size possible for the 8.1-family is 4.625 inches. When coupled with the supplied clearance for a 4.75-inch stroke, displacements of up to 638 cubic inches, are easily attained.

“We made the 8.1 block because GM no longer produced them. It is designed to be a stock replacement with the ability to upgrade performance beyond what the factory blocks were capable of,” says McInnis. “As an upgrade for your 8.1-equipped tow rig or boat it makes more sense, and for industrial applications, they are widely used.”

Again, Merlin IV on the left, World 8.1 on the right. From the rear, you'll notice the blocks are very similar at first glance, but the 8.1L block has passages and mounting provisions for modern electronics.

Which One Is Best?

With all the different variants, which one is best? That’s a very subjective term, but we tried to pin McInnis down on that one. “Inherently, there’s not much difference between them, but practically there is a huge difference,” he says. “The Mark IV style engine has the edge by far. There is an almost limitless range of aftermarket performance parts available from numerous manufacturers, enabling builders to create combinations for just about any type of use imaginable.”

Moving on to the Gen V/VI engines, as the blocks are the same castings as World’s Mark IV Merlin engines, there isn’t a power ceiling difference, at least not one that comes from the engine block. “The Gen V and VI can utilize many of the Mark IV components, but not all,” comments McInnis. There are a few performance parts available for the stuff that is specific to this engine.”

That leaves the Vortec 8100, which is definitely the red-headed step-child of the group. “While there are some aftermarket performance goodies available, it is a very limited selection,” McInnis says.


One of the subtle, but critically important differences of the 8.1L big-block, is the rampant use of metric hardware at the factory. That design shift further separated the Gen VII from the rest of its big-block brethren.

So when it comes to aftermarket performance, it appears the Mark IV pattern engine is the big dog, both in performance capability and variety of parts, which McInnis confirms: “For high performance builds, the Merlin IV (Mark IV style) would be the preferred choice by a large majority.”

However, McInnis was quick to qualify the statement. “It really depends on the application. In a marine application where an 8.1 was previously fitted it would make sense to build that type of engine because it avoids a lot of other changes which would be required to fit a different engine,” McInnis shares. “If all-out performance was the goal, then the Merlin IV would be the better choice, however.”
What’s right for you? We can’t answer that. That’s a discussion to be had between you and your engine builder, or between you and World’s tech department. Even though we’ve just barely scratched the surface of the 60-year legacy of the big-block Chevy, hopefully we’ve given you an understanding of the history, nomenclature, and differences between the factory generations, along with some of the aftermarket options available, which should keep the big-block Chevy as a viable option well into the twenty-first century.


http://garage.grumpysperformance.com/index.php?threads/big-block-chevy-info.710/

UN-machined SBC blocks have a nominal 9.0" deck height,
its very common to have the deck on a previously undecked block actually measure 9.022"-9.025"

SBCprintCustom2.jpg





UN-machined BBC blocks have a nominal 9.8" deck height,
its very common to have the deck on a previously undecked block actually measure 9.822-9.825

BBCbott.jpg


heres some calculators you might use
from a cost and parts availability vs the potential power levels you can generally expect there's
several BBC engine sizes that have consistently proven to perform rather well


the more common larger displacement combos ,these are
468 cid =454 .060 over bore stock 4"stroke crank
496 cid =454 .060 over bore + a 4.25" stroke crank
540 cid= 4.5" bore + a 4.25" stroke crank
572 cid=4.5" bore + a 4.5" stroke crank
632 cid=4.6" bore + a 4.75" stroke crank























gear spread sheet that comes in handy THANKS TO 1FATGMC

HERES OTHER INFO LINKS

















a few resources to allow you to calculate the ideal results
http://www.tmossporting.com/tabid/1805/Default.aspx

here's some different calculators

http://www.kb-silvolite.com/calc.php?action=comp2

http://www.wallaceracing.com/dynamic-cr.php

http://www.smokemup.com/auto_math/compression_ratio.php

http://not2fast.wryday.com/turbo/com...pressure.shtml
average the results


 
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they make BOTH clock wise and anti-clock wise rotation big block water pumps, Id sure check to be sure your using the correct version.
yes head gaskets do make a difference
https://www.felpro.com/technical/tecblogs/size-and-position-of-coolant-holes-on-gaskets.html

https://www.chevelles.com/forums/18-engine/247875-water-holes-big-block-head-gaskets.html

http://static.summitracing.com/global/images/chartsguides/f/fel-1012.pdf

http://garage.grumpysperformance.com/index.php?threads/bits-of-427-bbc-build-related-info.15543/
yes head gaskets do make a difference
https://www.felpro.com/technical/tecblogs/size-and-position-of-coolant-holes-on-gaskets.html

http://garage.grumpysperformance.co...ne-have-any-power-potential.12343/#post-81076

www.cartechbooks.com

Complete Cylinder Heads Guide for Big-Block Chevy Engines

Induction Systems for Building Big-Block Chevy Engines - Covers how to build 396 to 572 ci Chevy Big-Block Engines Step-by-Step
www.cartechbooks.com

as with most technology, there's a rapid ongoing improvement in what parts are available,
what the components can accomplish, what other matched parts must be used, and as usual the cost is always going upwards.

http://garage.grumpysperformance.co...hevy-oe-and-aftermarket-block-variants.15146/

bbchgs.png

http://garage.grumpysperformance.co...ig-block-chevy-head-gaskets.16420/#post-99663

003-big-block-top-end-build.jpg

When any dome-top piston is used, such as this JE slug, it is necessary to verify dome-to-cylinder head clearance. This can be accomplished by using clay or Dykem layout fluid. With our piston slathered up, we saw no transfer to the cylinder head (without a gasket). This means we will have at least our gasket compressed thickness (0.040-inch) clearance when the head is installed.
004-big-block-top-end-build.jpg

The next step is to verify piston-to-valve clearance. We installed checking springs on the intake and exhaust valves, turned the engine to 10 degrees before TDC (top dead center) for the intake and subsequently 10 degrees after TDC for the exhaust and used a dial indicator to measure free drop. With our relatively conservative lift, there was miles of clearance.

005-big-block-top-end-build.jpg


006-big-block-top-end-build.jpg

Next, we checked radial valve clearance using a transfer punch inserted through the valveguides. The corresponding punch mark on the pistons was scribed using a compass set to half the valve diameter. This check ensures the valve faces fit inside the valve pockets.
 
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https://2ovflq8a2if23r0004f29t3i-wp...ds/BBC-Mark-4-Block-InformationPacket-B17.pdf
https://www.cartechbooks.com/blogs/techtips/killerbigblockchevy/
http://garage.grumpysperformance.co...-aftermarket-block-variants.15146/#post-91792
many of the recently designed and currently sold aftermarket big block aluminum heads can be used on any of the gen iv-v-vi blocks
(obviously ask detailed questions before you purchase)
this obviously is not true of most factory heads or previously designed aftermarket heads

ictor-Reinz used to make a left and a right (different part numbers!) gasket pair to put Mark IV heads on to a "production" Gen 5 block. Those gaskets are now supplied by Mahle.

4918 is for the passenger-side (right) deck.
4923 is for the driver's-side (left) deck.

https://www.mahle-aftermarket.com/media ... a-g-05.pdf

http://garage.grumpysperformance.co...ig-block-chevy-head-gaskets.16420/#post-99663


https://2ovflq8a2if23r0004f29t3i-wpengine.netdna-ssl.com/wp-content/uploads/BBC-Big-M²-Block-Information-Packet-B31.pdf
 
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I got asked recently what block ID start with on a personal BBC build
no question a 4.5" raised cam bore DART BLOCK, and Id use the longer connecting rod options
with the 10.2" deck


http://garage.grumpysperformance.co...-calculators-and-basic-math.10705/#post-72061

http://garage.grumpysperformance.com/index.php?threads/big-block-chevy-info.710/#post-990

http://garage.grumpysperformance.co...-about-your-potential-dream-bbc-combos.14607/

http://garage.grumpysperformance.co...od-rod-length-too-stroke-info.510/#post-10311

http://garage.grumpysperformance.com/index.php?threads/picking-a-cam-for-street-strip-496-bbc.13384/

http://garage.grumpysperformance.co...esting-info-on-a-big-block-turbo-build.10680/

http://garage.grumpysperformance.co...le-turbo-all-steel-496-bbc-8-81-157mph.10615/

http://garage.grumpysperformance.com/index.php?threads/turbo-big-block.6835/



Dart Big M Sportsman Iron Engine Block Block Big Block Chevy 4.500 in. Bore, +.400 in. Raised Camshaft , 10.2" deck height :like:

Part Number: 301-31223455​


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Big M Sportsman Iron Engine Block Block Big Block Chevy 4.500 in. Bore, +.400 in. Raised Camshaft

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$3,330.34
Truck Freight: $184.99

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Big M Sportsman Iron Engine Block
  • Big Block Chevy
  • 4.500 in. Bore
  • 10.200 in. Deck Height
  • +.400 in. Raised Camshaft Location
  • Ductile Iron Main Caps
  • Sold Individually
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Ships on 05/03/23


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  • Details

    Iron Blocks W/Ductile Iron Main Caps
    Tech Tip - Oiling System

    Features:
    • Ductile iron 4-bolt mains caps for ultimate bottom-end strength
    • Siamesed extra thick cylinder walls to resist cracking and improve ring seal (minimum .300 in. thick with 4.625 in. bore)
    • Uses +.300 in. tall GM Gen VI style lifters
    • Crankshaft tunnel has clearance for a 4.500 in. stroke with steel rods without grinding
    • Main bearing caps have splayed outer bolts for extra strength
    • True priority main oil system lubricates the main bearings before the lifters
    • Lifter valley head stud bosses prevent blown head gaskets
    • Dual oil pan bolt patterns fit standard and notched oil pans
    • 220 BHN cast iron block material
    • .842 in. lifter bores
    • Press-fit freeze plugs
    • 2-Piece rear main seal
    • Note:

    Specifications:​

    Part Type
    Engine Block
    Quantity
    Sold individually
    Rear Main Seal Style
    2-piece
    Engine Block Material
    Cast iron
    Cam Bearings Included
    No
    Freeze Plugs Included
    No
    Main Cap Material
    Ductile iron
    Main Caps Included
    Yes
    Raised Cam Location
    Yes
    Assembled
    No
    Timing Cover Included
    No
    Cylinder Bore Diameter
    4.5 in (114.3 mm)
    Deck Height
    10.2 in (259.08 mm)
    Shipping Weight:
    300
    Package Height:
    14
    Package Depth:
    24
    Package Width:
    19.5
    Part Category:
    Performance Parts
    Part Fitment:
    Semi Universal



Features:
  • Ductile iron 4-bolt mains caps for ultimate bottom-end strength
  • Siamesed extra thick cylinder walls to resist cracking and improve ring seal (minimum .300 in. thick with 4.625 in. bore)
  • Uses +.300 in. tall GM Gen VI style lifters
  • Crankshaft tunnel has clearance for a 4.500 in. stroke with steel rods without grinding
  • Main bearing caps have splayed outer bolts for extra strength
  • True priority main oil system lubricates the main bearings before the lifters
  • Stepped main oil gallery (9/16 in. to 1/2 in. to 7/16 in.) increases the flow of oil to the crankshaft at high RPM, and front oil crossover eliminates internal oil leaks around the distributor shaft
  • Lifter valley head stud bosses prevent blown head gaskets
  • Dual oil pan bolt patterns fit standard and notched oil pans
  • 220 BHN cast iron block material
  • .842 in. lifter bores
  • Press-fit freeze plugs
  • 2-Piece rear main seal
  • Note:

Specifications:
Material:
Superior Iron Alloy
Bore: 4.500''
Bore & Stroke: 4.625'' x 4.750'' max recommended
Cam Bearing Bore ID: 2.1195'' - 2.1205''
Cam Bearings: Special coated, grooved, with 3 oil holes
Cam Bearing OS: +.010'', +.020'', +.030''
Cam Bearing Press: .002''
Camshaft Position: Standard
Cam Drive: Standard Timing chain, gear drive or belt drive
Cam Plug: Standard BBC 2-7/32'' (2.218'' dia)
Cubic Inch: 632'' max recommended
Cylinder Wall Thickness: .300'' min @ 4.625'' bore
Deck Height: 9.800''
Deck Thickness: Adequate for all applications
Fuel Pump: Mechanical pump provision
Fuel Pump Pushrod: Standard BBC
Freeze Plugs: Press in cup plugs
Head Gasket: Fel-Pro 375-1037, 1047, or 1067
Inner Head Stud: 2 slotted bosses per side
Lifter Bores: BBC .8427'' - .8437''
Lifter Galley: Raised .350'' for longer lifter bore
Lifter Type: Roller - Gen VI (+.300'' longer), Solid - Mark IV
Main Bearing Size: Standard BBC
Main Bearing Bore: 2.937'' - 2.937''
Main Caps: 4-bolt ductile iron
Main Cap Register: Deep stepped register on each side (No need for dowels)
Main Cap Press: .005''
Main Cap Bolts: All 1/2'', #2, #3, #4 have splayed outer bolts
Oil System: Wet or Dry Sump - Main Priority Oiling
Oil Galley, Main: Stepped, 9/16'' - 1/2'' - 7/16''
Oil Galley, Filter-Main: 5/8''
Oil Filter: Stock Oil Filter Location
Oil Pan: Standard pan bolt pattern, extra bolt holes provided for strokers
Rear Main Seal: Standard 2-piece seal, Fel-Pro 375-2918
Rear Main Thrust Width: 1.622'' - 1.624''
Serial Number: On main caps
Starter: Mounts in standard location
Stud Hole, Head: Blind holes
Timing Chain/Gears: Standard
Timing Cover: Stock Cover
Torque Specs: All 1/2'' bolts - 105 lbs
Weight: 4.500'' bore - 260 lbs


Specifications:​

Part Type
Engine Block
Quantity
Sold individually
Rear Main Seal Style
2-piece
Engine Block Material
Cast iron
Main Journal Type
OEM
Cam Bearings Included
No
Engine Block Style
Stock/OEM standard deck
Engine Block Style
Stock/OEM standard Deck
Finished Cylinder Bores
No
Freeze Plugs Included
No
Main Bearings Included
No
Main Cap Fasteners Included
Yes
Main Cap Material
Ductile iron
Main Caps Included
Yes
Raised Cam Location
No
Main Bolt Style
4-bolt
Engine Block Weight (lbs.)
260
Cylinder Bore as Shipped
4.49 in (114.046 mm)
Cylinder Bore Diameter
4.5 in (114.3 mm)
Deck Height
9.8 in (248.92 mm)
Manufacturer's Part Number:
31273444
Shipping Weight:
281
Package Height:
20
Package Depth:
26
Package Width:
31
Part Category:
Performance Parts
Part Fitment:
Semi Universal
 
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as many of you know one of my personal goals is to upgrade the engine in my car to a custom built big block chevy engine.
unfortunately, like a few of us I have this mental issue where I just can't bring myself to use cheap or inferior parts or do, or have other people do, slip shod sub par work, (I check and measure everything) I don't trust most machine shops to do top quality work,
after decades of dealing with many, thus were talking about building an engine based on a dart block, all forged components and matched to a full roller valve train, (READ VERY EXPENSIVE)
and as with most of us, I just can't convince the wife to give me $20-$27KK plus for a personal project, especially after spending $35K on a shop, so its going to wait awhile while I figure out the finances, more tools for the shop and ways to supplement my income for awhile, plus that nagging issue of greatly reduced mobility until my knees heal.

so if any of you have suggestions on what engine to build, or ways to supplement cash flow please PLEASE POST ,
so we can discuss various options & goals and ways to reach them.
now obviously I'm not about to go seriously racing (been there done that in the past and its a seriously bottomless money pit)
so durability and maybe 750hp-800hp is the goal which I've reached and exceeded more than a dozen times in the past building my own engines and engines for others, the key here is that once I build this I don't want to have to do more than minor maintenance and tunning
so I'm tending to think something in the 540-582cid, and I'm toying with the idea of rather low boost, intercooled, twin turbos and efi, this time.
not that that's really required , but Id like to run pump gas.
 
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This is on E85, so its easier, but modern EFI and good tuning makes power levels safe that was almost impossible to achieve 10-20 years ago.

817 hp Vortec 8100
 
thank you, Id seen something very similar, using e-85 before, but really appreciate that added input!
 
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Were you able to save one of your BBC engines for this project or will you be buying the block? Will the OEM block hold up to 800 HP?

How about a Excel spreadsheet to track prices on each component, then you will know when you have found a truly great price. Buying only when you find those rare deals, since you more time than money. Do you know what components you would accept for this build? Maybe have 2-3 possibilities for each.

Post your list here with prices so that others can help with the search and post when they see something better. This would mean the list would be continuously being posted with newer prices and when you have purchased a component.

Need help with the Excel spreadsheet, I'm available!!! Just give me a list of the components you want to track.
Or would you rather do this by hand???
 
great Idea, but currently Im starting out with zip/nada ,
and no I had to sell all 6 BBC engines , and 4 engine stands I had before the move
simply because of no room and shipping weights cost.
its only a temporary inconvenience, Ill work out the details and cash flow issues
and no the dart blocks or world product blocks are MUCH stronger than most OEM BBC blocks


 
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I found the Big M Sportsman for $2122, shipping is unknown. Lukovich Racing Engines does not seem to have online ordering. They went out of business in 2007.



Facebook post from 2022

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Id love to grab that but current financers won't allow unfortunately

link too bore vs stroke info on hundreds of engines
displacement = bore x bore x stroke x 8 x .7854

1/2 stroke + rod length+piston pin compression height,
should roughly equal block deck height ,

plus or minus a few thousandths,
minor adjustments in compression,
due to head gasket thickness and what the piston deck height is are common
common BB CHEVY piston compression heights are
1.270"
1.395"
1.520"
1.645"
1.765"
remember the blocks deck height, minus the piston pin height minus 1/2 the crank stroke will equal the required connecting rod length
OR
the blocks deck height, minus the connecting rod length, minus 1/2 the crank stroke. will equal the required piston pin height
http://users.erols.com/srweiss/tablersn.htm

http://garage.grumpysperformance.com/index.php?threads/big-block-chevy-info.710/#post-60300

http://garage.grumpysperformance.co...-displacement-street-engine.10961/#post-48359

http://garage.grumpysperformance.com/index.php?threads/tall-deck-big-block-related-threads.10391/

http://garage.grumpysperformance.com/index.php?threads/which-496-bbc-engine.12291/#post-60423

http://garage.grumpysperformance.co...g-block-head-comparison.319/page-2#post-56649

http://garage.grumpysperformance.com/index.php?threads/build-a-496-stroker-bbc.101/#post-49427

http://garage.grumpysperformance.com/index.php?threads/block-choice.10472/#post-43984

http://garage.grumpysperformance.com/index.php?threads/scat-cranks-related-info.10930/#post-47993

http://garage.grumpysperformance.co...apless-top-piston-ring-sets.10555/#post-44980

http://garage.grumpysperformance.com/index.php?threads/block-prep.125/page-2#post-58033

http://garage.grumpysperformance.co...-on-the-cheap-well-to-start.11739/#post-55365

http://garage.grumpysperformance.com/index.php?threads/what-big-block-is-it.11655/#post-54494

http://garage.grumpysperformance.com/index.php?threads/scat-cranks-related-info.10930/#post-47993

http://garage.grumpysperformance.co...-15-years-later-after-long-term-storag.10443/

http://garage.grumpysperformance.co...g-block-pushrod-guide-plates.4596/#post-52034

http://garage.grumpysperformance.com/index.php?threads/build-a-496-stroker-bbc.101/#post-49427

http://garage.grumpysperformance.com/index.php?threads/another-496bbc.5123/page-2#post-49183

http://garage.grumpysperformance.co...-calculators-and-basic-math.10705/#post-72061

http://garage.grumpysperformance.com/index.php?threads/another-496bbc.5123/

http://garage.grumpysperformance.com/index.php?threads/picking-a-cam-for-street-strip-496-bbc.13384/

http://garage.grumpysperformance.co...-car-craft-magazine-big-bang-big-block.10830/

http://garage.grumpysperformance.com/index.php?threads/striders-540bbc.1356/

 
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