nah, they aren't too big, not for a big ole turbo setup. they'd be fine. iirc, they are cut for a 4.125 already, so they'd be great for the new setup too.
My new setup wont be a 4.125 but plenty guys run these heads even on a 4.00 bore with great results. I'm just trying to get more opins.
As for suspension and things to hook the Glide on the transbrake should help a lil, but I do have tub front, coilovers, lowers, dbl adj uppers, solid bushings, and a anti-roll bar......thats gonna hopefully do untill i get some test n tune under my belt.
You could always get 205s and if you need more run the 225 program on them. I guess if I had the cake and your goals I'd go straight to 225s. I'd rather have a "too big" head and a smaller cam then have smaller heads and some monster stick that would be a PIA. If you're going to a block with a 4.125 bore and a turbo, why stay at 331, why not a 347 or 364? You must know more about turbo cars then I so you know the advantages of turbos and piston speed....
You could always get 205s and if you need more run the 225 program on them. I guess if I had the cake and your goals I'd go straight to 225s. I'd rather have a "too big" head and a smaller cam then have smaller heads and some monster stick that would be a PIA. If you're going to a block with a 4.125 bore and a turbo, why stay at 331, why not a 347 or 364? You must know more about turbo cars then I so you know the advantages of turbos and piston speed....
Enough boost can get you your goals, but as you know, a bigger head will get you there faster, pun intended
The more stroke, the more piston speed, the faster you spool, as you know. But for boosted applications and pushing that much power, you would want your piston rings further down, then what a short piston (goes with more stroke) might give you. It cuts down on heat to the piston rings.
AFR 225's would be great, but that is a lot of dough...
I'm sure those Trickflow heads can do the 'trick' later on though