scottyblank

So fairly new to the later model Mustang game. I bought a 1995 GT and want to get a few more HP out of the 5.0L. What is the difference between the GT-40 and GT-40P heads? Are there certain mods needed to use the Gt-40P heads such as intake or headers? Seems like the GT-40P heads are plentiful and cheap. Also, Explorer intakes are plentiful. I am working on a tight budget.

jwog666

just remember, those "cheap heads" are used with lots of miles on them, after you buy them you will have to have them reworked with a valve job, seals, perhaps valves and springs, and dont forget adjustable rockers and studs. now they arent so cheap. you would be better off to save up for a new set of AFR's of similar heads

mjr46

the gt-40/ explorer combo is so over used and underperforming, it isn't worth the time and effort for minimal gain.....

87 T TOP GT302

You question was GT40 vs GT40P heads. You may already know but in case you don't the p heads have smaller valve and the plug angle is different too. Also headers that fit one won't fit the other.
Go to Five.ohinfo and there is more information about these heads.
Yes you can get aluminum heads but the come at a hefty price too.

jwog666

you get what you pay for with new heads

88 orangepeel notch

+1 ^^^ lol

OP, what mods does your car have now, or is it stock yet ?

mongolchuck

If you can pick some up cheap, meaning under $100 then do it. They do add some power with some other supporting mods like intake and throttle body. But if you're spending more save up for some aftermarket heads. The p heads have smaller combustion chambers and slightly smaller exhaust valves. They do outflow the regular gt40p heads but not substantially.
I have the p heads on mine and because I got them for $60. Get new springs and a three angle valve job with them. Even the stock ho cam can be too much for the explorer springs.

scottyblank

Car is completely stock. Compression check shows engine is good. Not burning oil and holds good oil pressure. This car is a hobby car meaning it will be taken out for an occasional cruise and to the local drag strip for midnight drags.

I would like to get this car in the low 12's, high 11's. It does have an auto trans and 3.27 gears at the moment.

My budget is tight, so I'm looking for cost effective mods that will make the car quicker but keep it completely streetable.

mongolchuck

You'll need gears and some transmission massaging. The aod does not do even occasional track work well. As has been said on the forum many times, cheap fast or good. You can only have two of the three; and usually just one.
GT40 stuff is an upgrade over stock but usually no more than 25 hp. It definitely has the benefit of being inexpensive and oem parts are reliable. There are trade offs for anything you want to do. The gt40 upgrades are tried and true so do it if you want just keep your expectations low.

88 orangepeel notch

So you've got a completely stock SN Mustang, and your on a tight budget.

Scrap the heads/intake idea for now. Throw a set of 3:73/4:10 gears in the back and enjoy those while you save up for the next mod.

And no disrespect meant, but to get your car in the low 12's/high 11's is going to be alot more $$$ than you think. Make a wish list of what you'd like to do to your car, then double that amount. Now your in the mid 12's......

I'm not saying it can't be done, or that you shouldn't even try. But from your first post you said "tight budget". That's a major drawback from running fast at the track

Good luck in whatever you decide, and we're always here for honest advice.