[Formulabruce]

Originally Posted by Mike Davis

I am a big fan of the 4" stroke engines. If it was my build I would go 4". Moves the rpm range up a little bit and kills a little bottom end.

yup kills the Torque in the RANGE YOU DRIVE........
Reason why the dynos don't even care what happens below 4,000 RPM
but who REALLY Drives ABOVE 4,000 RPM for longer than 15 seconds?
Yup, overbuilding "happens"
And after all that, the HP is only a estimation, even on a dyno......
How many folks have switched out their Torque converters for Horsepower converters?

[Mike Davis]

Originally Posted by Formulabruce

yup kills the Torque in the RANGE YOU DRIVE........

The 4" stroke has plenty of low end torque for any street car.
I think it would be a lot easier on the stock drivetrain the OP is running.

[tom s]

2X on 4in.Tom

[Formulabruce]

My Point is just why have max power where you do NOT use it. For a street engine this makes no sense, and costs more money.
Fact>> In this "street" section people get "influenced" into a DRAG built engine.., and FEW actually do drag race.
I have met many people that say they "wished they had Not built their motor at 11:1" or solid lifters, or forged pistons, etc..
On the Street DRIVEAVILITY is Job #1
I am all about "excitement" but I wouldn't put a 9 ton AC system in a house that only needs a 3 ton system.... just to
say my house has "This" .
Maybe it is just about bragging rites ??

[Mike Davis]

it cost no more to build a 4" stroke than a 4.25.
Killing a little bottom end of a stock suspension street car is not a bad thing. Easier on ALL drivetrain parts.
No one is telling the guy to put a solid roller or 11:1 comp.
I guarantee the OP would not be able to tell much difference in driving the 2 on the street.

[Verdoro 68]

From what I can tell, the 4.25 kits are a little more prevalent and cost about $500 less than the 4.00 kits. Not a huge amount in the scheme of what this will likely cost on the whole, but worth thinking through the benefits/drawbacks since I'm starting from scratch.

I chatted with a local Pontiac builder yesterday about what I want from the engine. He walked me back from a stroker at the start of the convo but by the end of it he was thinking the torque of a 4.25 stroker would be a good match for what I use the car for, which is mostly around town lower RPM driving and hot rodding here and there.

That said, I got a big box of parts from KRE today including the $450 cam I was waiting 3 months for - that will be too small for a 472. I suspect I'd want a different cam for a 4" stroker too? Save $500 by getting a 4.25 stroker kit, spend $500 on a new cam that works with the bigger cubes. The most economical path here is building a 400 again, but what fun is that?

[grandam1979]

If you had your choice would you put a 400 428 or 455 in it that will give you the answer your looking for. Don’t forget 494 so you got a lot of choices starting from scratch you can do any of them with your block.

[Verdoro 68]

All things considered, I'd build a RAII-headed 428 for no other reason than parts were available in '68. Sort of a one of none fantasy build if I raided the parts counter in '68. With Pandora's box opened and now looking at my options to solve gripes I had with previous incarnations of the car, I keep having to remind myself this project came about because of the heads.