Re: gt40 vs gt40p
 

alright im new to this forum, saw this topic and thought it might help, and your inputs may give me a better idea of what im trying to do. i recently bought an 89lx, it now has 93000 miles on the stock 302. im not trying to make it crazy fast, but pretty quick and sounding right, would be nice and heads were my next step.

list of what i have done so far...
373s
subframe connectors
lakewood shocks and struts
lakewood upper & lower c/as
performance rotors and hawk hp pads
underdrive pulleys
bbk cai
shorty headers
catback exhaust...

i plan on removing all my smog shit, cutting my cats, and throwing an xpipe and new mufflers to beefup my exhaust.

i just pickedup a cobra intake that hadabout 1500 miles on it, brand new tfs1camshaft, brand new 70mm accufab tb, brand new 75mm powerflow(or something like that) maf matched to 30lb injectors..
and now i have a couple offers from locals with a set of iron gt40heads, completely re done to make them pracitically brand new 400$, and gt40p heads 450$ ( but i can probably get him down to 400 as well ) do i buy one of those? or pay an extra couple hundred and get an aluminum set? do i need to get roller rockers, pushrods, springs or anything i like that?

im hoping ill be hitting somewhere close to 290 - 300 hp? if not what else can i do, or change thats not to unafordable.

Re: gt40 vs gt40p
 

now hold up just a second here guys, i am new and have been reading some of these posts let me clarrify that i am running a 347 stroker with p heads, 36lb injectors, c&l mass air meter, eagle crank, comp cam pistons, trick flow intake. my heads have a valve upgrade along with springs upgrade. last sat i ran a 8.68 at 89mph in a 1/8 on street tires spinning in fourth a the finish. these heads will with some wrk and correct combo put down serious hp

Re: gt40 vs gt40p
 

I have to agree with the post above, a few of you should take a look at Tinman's videos going high 11.6- low 11.7 with gt-40 iron heads on a N/A 302, or his dyno videos of his 347 putting down 360 RWHP, 355 RWTQ with another pair of gt-40 iron heads.

Re: gt40 vs gt40p
 

I put a set of GT40P heads on my mustang last summer from the stock heads.The P heads are sweet and do flow better.I was always fowling plugs all the time and now the plugs are a pretty carmel color.My engine is not stock its been built to run and runs so much better.Any GT40 heads are better than stock heads on the mustangs.Mine came off of a 97 or 98 ford explorer.They are just a all around better head.