Big block road race build 572

[richiev88]

Hi,
Currently been shopping ( what else to do in lockdown) for parts for my new roadrace engine for my 1970 Camaro
Currently I have BMP tall deck 10.2 alloy block
4.5 bore CP Carrillo pistons, small dome,
crower 4.5 crank,
AFR 357 cnc heads,
crower rocker gear,
Jesel belt drive.
crower 272, 282 @50 106, .700 valve lift solid roller.
crower 6.535 rods
Compression comes out at 11.58:1,
103/105 race gas
Tall single plane intake and 1150 dominator carb.
5 stage dry sump oil pump, large pressure section
I have been running a short stroke SBC for a number of seasons. Most of our fast guys have gone to SB2.2 nascar power of which they stroke to 410cu.
Not wanting to run a "team" engine and for a point of difference I have gone down the big block route
So I'm hoping for a bit more HP/ TQ and much longer engine life as I'll only turn it to 6500rpm
I know this is not the norm, we had the heads cam and crank/ rods from a low hour build.
I know there is a bit much cam and heads are big, but we run 275mm road race semi slick so are traction limited.
Perhaps the cam and heads will soften the bottom end a bit ??
Any guesses on HP and torque potential from this Combo

Richie

[swampbuggy]

Here is a guesstimation 900 HP 780 TQ.

[bob460]

My guess..........875hp & 760tq

[richiev88]

Wow, I am guessing 830-40, but hey like yours better

[BILL-C]

How much road race experience do you have?

[hoffman900]

How much road race experience do you have?

+ 1

Sounds like a NASA class? I can’t think of any other sanctioning body that allows such a wide range of platform in a class. How competitive is your class?

Edit: NM, just realized your in New Zealand. What are the tracks like there? The ones I can think of are tighter and slower than the big tracks here in the US or Europe.

[dannobee]

Any way that you look at it, it'll have almost 200 lb ft of torque more than a 410" SB2.2. Is traction control legal in the class? Because you're gonna need it.

SWAG = 572 x 1.3 = 744 lb ft of torque. 650 lb ft @ 7000 = 866 hp

[LoganD]

Just be careful, you're going to have a hard time making this engine live in a road race situation.

[Momus]

Way too much low and midrange for a Thundersports circuit racer.

Which track in NZ has a 200 mph top speed?

That chassis/tyres will be so overpowered it will be undriveable.

[Walter R. Malik]

Hi,
Currently been shopping ( what else to do in lockdown) for parts for my new roadrace engine for my 1970 Camaro
Currently I have BMP tall deck 10.2 alloy block
4.5 bore CP Carrillo pistons, small dome,
crower 4.5 crank,
AFR 357 cnc heads,
crower rocker gear,
Jesel belt drive.
crower 272, 282 @50 106, .700 valve lift solid roller.
crower 6.535 rods
Compression comes out at 11.58:1,
103/105 race gas
Tall single plane intake and 1150 dominator carb.
5 stage dry sump oil pump, large pressure section
I have been running a short stroke SBC for a number of seasons. Most of our fast guys have gone to SB2.2 nascar power of which they stroke to 410cu.
Not wanting to run a "team" engine and for a point of difference I have gone down the big block route
So I'm hoping for a bit more HP/ TQ and much longer engine life as I'll only turn it to 6500rpm
I know this is not the norm, we had the heads cam and crank/ rods from a low hour build.
I know there is a bit much cam and heads are big, but we run 275mm road race semi slick so are traction limited.
Perhaps the cam and heads will soften the bottom end a bit ??
Any guesses on HP and torque potential from this Combo

Richie

Personally, I think I would use a lot less stroke with a longer rod and make it a 509 ...
you don't need that extra torque and turning it about 7,000 with more gear would help.
Looks good though.

[Ron E]

I have to agree with Walter. I don't think you will be able make your torque manageable with a 572 . A 509 at 7K will make a lot, no doubt. And, 7k RPM is well within current endurance valvetrain pieces.

[CamKing]

106 LSA is way too tight. That 4.5" stroke is going to have a very peaky torque curve, and that tight LSA will make it worse. You'll spend all your time trying to keep the back end from passing the front end. If you have to stick with the 4.5" stroke, I would go with something around a 112-114 LSA.

If it was me, I would go with a 4" stroke, and turn it 7,000rpm. You'll have a broader power band, and the engine will last longer.

[hoffman900]

A Trans Am chassis can barely handle the torque from a NASCAR spec 358ci engine. Really can’t imagine a 275mm tire putting down what you want, even with a blank sheet chassis.

[PackardV8]

I don't have the BBC road race experience of some here, but my limited exposure is they have severe crankcase pressure pumping problems at sustained high RPM. The larger their displacement, the greater the crankcase pressure to be managed. Using multi-stage dry sump pumps, it can be difficult to keep the oil inside. Even with a torque plate and hot honing, keeping the cylinder walls round is a challenge on a 572". Better ring seal is key to reducing crankcase pressure.

[Caprimaniac]

Sounds fun.

I want to add this: Do you have a cover for the belt- drive? Debris will eat it unless.

Agree on Camking to keep it less peaky, and also de-stroke idea is something I would look into.

Else; oil Control is everything, and it seem like you have taken care of Things there.


On crankcase pressure pumping. Looking at a SBF BMP Block have breating Spaces between cylinders, don't know about the BBC...May help...