Black8Banger

iTrader: (9)

With AFR 225s and a Trex cam, do you have to flycut the pistons? If so, whats the biggest cam you can go without flycutting? Anyone know off the top of their head how much you have to flycut them?

LSONE

iTrader: (1)

t-rex is not a very good cam for that application at all, but i wouldnt imagine you would need flycut

Tony Mamo @ AFR

iTrader: (13)

I assume you milled the 225's??

If so how much?

Assuming low-mid 60's you WILL be flycutting....

(2.080 valve creates more V to P issues than the 205's with the smaller 2.02 valves).

Black8Banger

iTrader: (9)

I do not have either the heads nor the cam. I am looking at going with a 402 sometime next year but I was thinking of going ahead and getting the FAST 90/90 Intake and throttle body along with the 225 Heads to be used on the new motor. I was thinking of using them on my stock cube LS1 for now and switch to a bigger cam. I assume this would be an ok move since I would use that intake and heads on the 402.

Also, what do you do about the difference in the bore size between a stock ls1 and the 4.000 on the 402?

Tony Mamo @ AFR

iTrader: (13)

The problem will be chamber volume....a large chamber on a 402 is perfect but will kill a 346 unless its used on a blower application that will benefit from the lower static compression ratio. If you mill the head for the smaller motor then you will need a pretty good sized dish on the larger combo....not ideal in my opinion.

As far as the bore size differences, ANY 225 headed combination must run a 4.125 minimum bore gasket anyway so technically both combinations would take the same head gasket.

Tony M.

Black8Banger

iTrader: (9)

Thanks Tony! Youve been a great help!