[screamingchief]

Originally Posted by 69Farburd

You've given me a lot to think about. I guess the main question in my mind is what combo is going to make the car go fastest? I don't go to the track much, but want to be fast when I do. But it does need to be streetable. I guess it is hard to get the best of both worlds. Does more compression mean more hourspower? If it does, would I be better off just zero decking the block, runing the combo I have with a possible cam change and continue adding race fuel to my gas?

Well,if you think about this,a large part of the reason your where you are right now is due to the fact that this motor very well may have damaged the rod bearings due to detonation,this despite your best efforts via mixing fuels to try and account for any CR issues.

So to use a lame cliche',how's that working for you?

If a combo like I described is'nt "enough" power,then there are simple ways to address that,the first being adding more headflow via porting the iron heads or better flowing aftermarket aluminum heads or such.

But a well built unported iron head 428 with good tuning should easily be able to make 425 hp no sweat,even @ 9.5:1 cr.

And with the slight CR drop,you also wont have to be super conservative with the timing curve either.

The zero decking often adds roughly like .25 to .5 a point of CR depending on how far down the pistons were to begin with.

So in some respects your just compensating for that by either adding more dish or a bigger chamber.

But what I'm saying is I would drop it just a bit more to make it more pump gas friendly and eliminate the need to mix fuels,and then make up for that slight loss in those other changes like using a better cam and more aggressive tuning and maybe more headflow & such.

But the choice is yours.

Good luck with it.

Bret P.