No replacement for displacement?

Time to order the crank/rods for my stroker, current pistons will allow for a 4.3/6.8 (532) or a 4.5/6.7 (557) combination. will be a track only engine that sees a mix of 1/8 and 1/4 duty. Car is 2500lbs with a C6 trans. Using a set of SCJ's with minor cleanup and backcut valves, victor intake with 1150 dominator, customs grind solid roller, compression should land around 13.2-13.8. Eventually will have the heads ported and the intake (or switch to mafia) What stroke/rod combo would you choose and why?

For absolute TORQUE ... that is true.
Usually there are some other parameters which enter into such a decision.

There is a lot more to the car than what it weighs and it's transmission.

True enough, it is a ladder bar car, 32-14 tire, Afco DA's , 45F/55R weight distribuition, trans has low gear set in it now (may have to change that? ), convertor and rear gear will not be picked until dynoed.

with a c6 and ladder bars you aint gona need the low gear.532or557 will have all the tq you can deal with run'n a 3spd.

cool40 wrote:with a c6 and ladder bars you aint gona need the low gear.532or557 will have all the tq you can deal with run'n a 3spd.

I'm learning that now

With big tires, a three speed trans and only 2,500 pounds, I would use a 4.3 stroke with tenth more rear gear and rev it 400 RPM higher.

Even a 4.150" stroke with 3 tenths more rear gear and 900 RPM higher.

WHY...? the ET's will be about the same however, it will be more consistent on every track surface.

Thanks Randy, you've confirmed my suspicions. Also looks like the low gear set will be coming out when changing cases.

Personally I would throw a glide in it and be faster and lot less hassle than having to shift twice...

the Coug wrote:Personally I would throw a glide in it and be faster and lot less hassle than having to shift twice...

That was my original thought, but I already have a capable C6 in a small block case. And with all the other changes I am making (brakes,chute, BBF, headers, engine plate, carb, etc,etc) keeping the C6 is just one of the compromises I am willing to try to get back out this season.

I've now switched to a glide, would you still stay 4.3 stroke?

Now you can use the 4.5 arm IMO....... Let the convertor do the talkin' !!

Diddly wrote:I've now switched to a glide, would you still stay 4.3 stroke?

When the intake manifolding and cyl. heads are highly developed the 4.500" thing will be quicker. In the mean time they'll be very similiar in performance.
The bigger is better thing don't work as good as it could unless one can 'feed' the extra inches......i.m.o.