Dyno 2000 Camshaft Possibilities For 396

heres a set of stock oval ports after port work,
you can use as about average,
for the better cast O.E.M. stock muscle car era,
cast iron oval ports with some port & bowl clean up,

Lift Intake Flow (CFM)
Oval PORT
.100" 73
.200" 140.2
.300" 211
.400" 273.2
.500" 302.8
.600" 315.3
.650 313.8
.700"311.1


Lift Exhaust Flow (CFM)
Oval
.100" 60.8
.200" 107.7
.300" 139
.400" 165.2
.500" 186.4
.600" 202.3
.650" 208.4
.700"216.5-



https://www.airflowresearch.com/content/catalog.pdf

heres the 265 afr heads
265afrt.png


heres what I would use.. 300cc afr oval port heads

300afrt.png

Ok, but where are the exhaust numbers?
 
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they are posted? ..ok, I see they did not show, I reposted them
 
I see them now, thanks!

Sometimes I've seen when that happens the text is white and background is white,
therefore you can't see them.
 
Depends what You want.
It's a past NHRA Super Stock engine used a 396 BBC.
A Few have cracked 700-750 Hp with them factory heads and full Race cams.
496 BBC always done here by Grumpy.
To build it you have to scrap your entire 396.
Only the Tunnel Ram will be used.
Surely there must be a way for decent HP? the speedway guys are pulling 800 hp in their 406 SB engines. All though they are methanol race motors....
 
perhaps theres a miss-understanding, the 396 BBC can easily potentially produce impressive power, back in the 1970s-2000 or so we used to routinely swap a 454 crank and rods with custom pistons and a re-balance job with a 454 flywheel and damper in a 396-402 block to build a stroker 433,
the basic 396-402 has a great deal of potential,
its got larger valves, in many cases better and larger ports, a stronger, crank, cam, rods and block,
(especially if aftermarket components are used)
the main reason the 396 is not all that commonly built to serious power levels is,
the fact that the similar 427-454-,477-,496-,540-,572-,632- cubic inch displacement versions of the BBC,
can be built on similar looking engines for in many cases just a bit more cash.
even if your goal is a lower cost build I,d much rather start with a 396 BBC, especially the 375 hp rated version if you were lucky enough to find one.
(those made well over 450 hp stock)_
it almost always comes down to dollars spent vs potential horse power....
if a 406 SBC makes 800 hp, thats roughly 2 hp per cubic inch
why build a 396 BBC , if the cost to build a 427- 496 BBC, being similar,
that could get you significantly more torque and horse power, is the question that always comes up?

1000 plus hp BBC engines are common in some race venues
Photo266_2.jpg
 
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http://www.superchevy.com/how-to/0707ch-small-block-vs-big-block/

http://garage.grumpysperformance.co...ce-between-a-400-sbc-and-a-396-402-bbc.15087/

http://garage.grumpysperformance.co...402-bbc-with-a-4-454-crank-or-even-4-25.2165/

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

http://garage.grumpysperformance.com/index.php?threads/496ci-revamped.14642/

http://garage.grumpysperformance.com/index.php?threads/a-mid-range-454-bbc-build.8215/

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

https://www.shafiroff.com/
]
no ones suggesting a SBC can,t produce amazing power, but its basic architecture
limits its potential, where a much larger displacement BBC, might have difficulty , making
the same power per cubic inch, its a no contest match-up when you start to exceed,
or you need about 800 hp or more if the rules don,t limit your engine displacement.
The valve positioning of the BB heads is much improved over the SB.
The BB heads also don’t have the two center exhaust valves together which helps even heating.
2.30 intake valves and 1.88 exhaust valves are common in many aftermarket heads .
I don,t see and reason why a well designed and properly assembled 396 with a roller cam and better heads like the AFR 300 cc could not easily exceed 600 hp , if you used enough compression and that tunnel ram type intake , and race octane gas, but I doubt youll hit the numbers you posted using reworked O.E.M. heads

https://rehermorrison.com/rech-talk-9-the-big-bang/

Tech Talk #9 – The Big Bang


By David Reher, Reher-Morrison Racing Engines

I haven’t checked the Environmental Protection Agency’s list of endangered species recently, but I’m willing to bet that the small-block V8 is on the list. While the small-block is still the engine of choice in oval track racing and several NHRA sportsman eliminators – notably Stock, Super Stock, Competition, and Pro Stock Truck – the big-block V8 has simply taken over the heads-up eliminators and fast brackets.

There is a reason why the Rat motor reigns as the king of the quarter-mile: the big-block Chevy is durable, heavy-duty, and the best bargain in motor racing.

That’s a total reversal since the days when Buddy Morrison, Lee Shepherd, and I were winning races with small-block Chevys we’d built with junkyard blocks and $25 reground crankshafts. Back then, big-blocks cost big bucks. Today, however, it’s virtually impossible to find a usable 400ci small-block in a salvage yard, and a CNC-machined Bow Tie small-block will set you back $2900. Do the math: You can buy a brand-new Gen VI big-block, an aftermarket forged steel crank, steel H-beam rods, and a set of custom pistons for about the same price – and you’ll end up with a motor with significantly higher performance potential.

Big engines make sense for weekend warriors – the bigger, the better. An engine’s lifespan is directly related to the number of cycles it turns. If you have a large displacement, relatively low-revving engine, it will turn many fewer cycles in a season than a high-revving, small-displacement motor. This means the big engine’s rods will be stretched and its valve springs compressed fewer times. Its roller lifters will make fewer revolutions, and every moving part will be subjected to less stress, wear, and tear.

If you want to race as cheaply as possible and still have a reasonably fast car, my advice is to build or buy a low-rpm, big-inch motor.

You should also have a firm idea of how much horsepower you need to run the number in your particular eliminator. For example, if you need 800 horsepower to make the cut for the Quick 32 at your local track, that’s readily attainable with one of our relatively inexpensive Super 502 engine combinations. If a customer wants a 1200-horsepower engine, I can do that pretty reasonably as well if we make it big – say 588 or 600 cubic inches – and put a nice set of 14-degree Dart Big Chief heads on it. But if someone asks for a real hot rod engine that produces the maximum power for its displacement, then the price tag quickly escalates to Pro Stock levels.

You can compare buying an engine to buying a piece of tubing. If I order a three-foot length of steel tubing with a certain diameter and wall thickness, the clerk at the metal supply can quote me an exact price. But if I want some exotic aerospace material, and I don’t know the length, diameter or thickness, there’s no way the guy behind the counter can give me a price. It’s the same with racing engines: I know what it costs to build a 1,000-horsepower bracket racing big-block because I’ve done it dozens of times – but I have no idea what the price tag would be for a 1,400-horsepower Pro Stock big-block because no one has ever built one.

I’ve noted in previous columns that rpm plays a major role in determining the cost and maintenance requirements of a racing engine. Any engine that regularly turns more than 7,500 rpm really needs lightweight valvetrain components – titanium valves, top-quality rocker arms, serious valve springs. On the other hand, if a 7,000 rpm motor will meet your power requirements, you can build a relatively inexpensive engine that will be virtually bulletproof.

So how big is big enough? I’m sure some engine builders will disagree with me, but I believe the practical limit for a conventional Chevy big-block with 4.840-inch cylinder bore centerlines is 615 cubic inches. I want to emphasis the word “practical.” Back when Buddy, Lee and I raced Mountain Motors, we built 655ci Rat motors with standard blocks, but those were extremely labor intensive. When you consider issues such as camshaft, connecting rod, and oil pan clearance, a 4 5/8-inch stroke crankshaft is about the realistic limit for a standard big-block.

If you want to build a big-block with more than 615 cubic inches, my advice is to go all the way to an aftermarket block with a raised camshaft, spread oil pan rails, and 5.00-inch cylinder bore centerlines. There’s no reason to beat your brains out to get 20 more cubic inches when it’s just as easy (and just as expensive) to build an engine that’s 100 cubic inches bigger. I wouldn’t even consider a block with a 4.900-inch bore centerline like we use in Pro Stock; the little bit you gain with .060-inch more spacing between the cylinders simply isn’t worth the expense for a bracket-type engine.

Aftermarket manufacturers have tooled up to support the new generation of bigger big-blocks with special cylinder heads, oil pans, camshafts, and other specialized components. It’s possible to build a 706ci Rat for Pro Mod or a monster 816ci Mountain Motor – but the price will reflect the cost of the exotic components that are required.

I clearly understand the appeal of big-inch engines for bracket racing and heads-up eliminators. If the rules don’t limit the size of your engine, cubic inches are definitely your friend. They help keep costs down and reliability up. And you can’t have too many friends
 
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Used Grumpy's numbers for the OEM BBC heads with port and bowl clean-up.

OEM_BBC_HeadFlowNumbers.JPG

Dynomation can take cam numbers at .050" and estimate the seat-to-seat numbers, but it can't go in
the opposite direction. So I used a generic cam from Dynomation and modified it to match the valve
event timing numbers to 19Brookwood60's numbers on page 1.

Sim02 Cam File
Sim02_CamManager.JPG

Sim03 Cam File
Sim03_CamManager.JPG

Sim03_Sim02_Compared.JPG
.
 
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throw a set of these 300 cc AFR, heads on a 13:1 compression ratio 396,-402- or a stroked 433,displacement version,
matched with a cam like a crower 01523 solid roller cam, run E85 or race octane gas,

https://www.crower.com/chevy-396-454-series-230-high-rpm-roller-cam-3.html

Duration @ .050" Lift: Intake / Exhaust 278 / 287

lift at valve in .743 / ex .728

intake 33/65@ .050"
exhaust 77/29 @ .050"
http://garage.grumpysperformance.com/index.php?threads/crowers-valve-timing-charts.4299/

https://www.jegs.com/i/Edelbrock/35...VzF6GCh31kw-TEAQYAiABEgLesfD_BwE&gclsrc=aw.ds

300afrt.png

a 4000 rpm stall converter and 4.11 rear gears in a light car, long 33"primary,length 2.125" diam
headers, with a 18" long 3.5" collector, and potentially you might even consider direct port, wet nitrous

https://www.summitracing.com/parts/edl-71852/overview/make/vauxhall/model/victor
 
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Rick,,, could you possibly run that revised combo above:praying::rolleyes::D
 
Ok, so I did another pop quiz and everyone failed. I got the torque curve swapped between the two
Sims. I will correct the curve immediately above so it's correct for everyone reading.
 
Got the wife's car fixed yesterday, so it's back to having some fun !

I made all the changes suggested by Grumpy in post #30.

Crower_SR_01523_743_728.JPG

Sim04_SR_Crower01523_743_728_Sim03.JPG

The header sizes came pretty close to Grumpy's suggested ....
long 33"primary,length 2.125" diam, with a 18" long 3.5" collector

Sim04_HeaderSizes.JPG
.
 
well its rather obvious theres some issue with the software or the data ,
simply by looking at that predicted data, and the resulting predicted tq curve

btw where did you find the cams spec card?:like:
 
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AFR 300's do flow good numbers with a decent roller cam.
I understand what you are saying Grumpy about cubes is king for affordable HP.
Its hard for me to surrender my faithful 396 that served me well for the last 30 years.
But alas I probably need to let it rest and build a 496.
I like the data the two of you have put up, you seem to have an amazing library of relevant information, this is why I enjoy the forum.
I think I will be upgrading my DD2000 software with what Rick is running, it seems alot clearer when you are doing the numbers.
 
I think the web site was down, I tried numerous times

https://www.crower.com/

btw
RICK
I've used a roller BBC cam, in a similar BBC in the past,
in a serious 13.5:1 compression 427,BBC
a crane 138631
crane138631.png

https://www.summitracing.com/parts/crn-138631
you can use this as seat timing
in 45-79
ex 93-39
seat timing
why not try that and see if the software likes that better?
 
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