White Cobra

i have a 95 cobra with cast iron gt-40 heads should i port and polish and redo those heads or go with some new aluminum heads am putting f-303 cam in if that matters, what do u guy's think? cause a machine shop said to do the gt- 40 would be about 800 but that is fully ported and i can get aluminum gt-40 x turbo swirls for a $1,000 i don't know what to do. whats the better performance? Thanks!

Black Snake

Yeah whats only $200 more id go with the aluminum.

sick95gt

Yeah, and you'll lose weight too.

posnick

$200 is not much when it comes to better heads. Definitley go with aluminum

mississippiheat

The question is will the "x" heads flow enough for your needs or will you end up doing more work on them to meet the "iron" flow after the work is done.

Derf00

Make absolutely certain to get the right head gasket too! It never fails that when switching from cast heads to aluminum on a cast block that someone forgets to use the right type of gasket. Use a Felpro pressed steel gasket 9333PT1. The special coating on the steel as seen in this picture http://www.pickproparts.com/pictures...rtnum=9333PT1% helps to keep the thing sealed even though the metals heat and cool at different rates.

sastangman

if your gonna spend a 1000$ on gt-40x heads i just dont think
your gonna get the performance your are looking for, spend a little
extra and get some quality stuff like canfield,trick flow and
of course afr's

wildstang87

i would go with the afr 165s, for around $1200 you get 35hp out the box, save around 40lbs, and dont have to get new headers. you can probably sell the gt 40s for a few hundred bucks(im looking for a set) and that will bring the overall price down.

Quik

just get those GT40s worked over. many ppl use them and have great numbers. save that 200 bucks and put it towards other things. those heads when back from machine shop will out flow those X heads. also the only advantage to aluminum heads is weight. actually head vs head a iron head will flow better. and aluminum will warp easier then iron. now if you went with those Xs youll need head work on them to get them to really flow well.. it comes down ot what your wallet has to spend

stanglx2002

i agree with OH the iron heads can withstand heat a lot better and wont warp like alumumim heads would and with $200 dollars you can get yourself bigger injectors like 24's when you put everything back together. you will need the extra fuel with more air flow. also a afpr would be a good idea too so you can adjust the fuel mixture richer or leaner