How much will aftermarket heads help?
 

Hello,

Some of my mods were to replace something that was broken (not necessarirly the biggest HP gain to $$ ratio) but here is everything (a few soon to be installed):

MAC Cat Back Exhaust
MAC Cold Air Intake
MAC Equal Length Shorties
MAC Pro Chamber
Granetelli 75 MM Mass Air Flow Sensor
3.55 Gears
Trick Flow Steet Intake Manifold

If I decided to get heads and maybe a more aggressive cam, how much would that give me, what would my estimated 1/4 mile time and HP (crank and rwhp) be?

Thanks,
DoranW

I'm not that good with estimates but it would be alot. You have the trick flow intake but it won't show much gain with the stock heads. You need a good head to show its potential. If you went with the trick flow heads and a cam to match I'm sure it would be alot.

With a good set of Al heads like TFS Twisted Wedge and a good cam you would be around 290-300 at the flywheel. You'll have to upgrade your fuel system to 24 or 30# injectors, fuel pump and re-calibrate you MAF. You should also invest in a 65mm or 70mm TB. If you do all that you should be somewhere between 315 and 335 HP at the flywheel. IMO.

What kind of car do you have again, It is an SN95 right? (94-95 GT comes to mind)

Oh and quarter mile times, assuming you can drive (no offense) would be somewhere in the mid 13's (depending if you just do the heads or the other stuff)

Actually it is a 1990 Mustang 5.0 LX in just about perfect mechanical condition. Unfortunately, it is an auto though... :(

Thanks,
DoranW

Don't bother upgrading the AOD if you don't like it now chances are you won't like it beefed up either. Swap out your auto for a 5 speed manual...something like a Tremec or T-5 World Class...you won't be sorry you did. I don't think that the swap kit is too much either.

BTW...aftermarket heads are worth every penny. Stock heads flow like crap...you definitely want the benefit of bigger intake and exhaust ports as well as bigger valves. Less weight with aluminums too.:D

Do you know how much the kit would be? Assuming I want a heavy duty clutch and I want to replace everything that might be a problem down the road?

I think you would have more like 350-365 FWHP and high 12's in the 1/4. I bet my car has 285 HP with the stock port and polished heads.

You might see 350 FWHP with heads, a big cam and full exhaust. You would need to get rid of the cats to see 350 FWHP with what you have listed. The TB is a must buy.

I think 95mustanggt is about right (with what he listed), 320 FWHP, give or take. You lose a bit more power to the wheels with the auto, but you should still be able to run low 13's.

The 3.55's are not the best gears for an auto. If you had a 5-speed and 3.73's you might tap some 12's with good driving.

Oh, and get a good set of rockers if you buy heads. Stock rockers are junk.

I did a before and after dyno pull on my car a couple months back. With the stock long block (stock motor heads and cam), 73mm maf, 65mm tb, underdrive pullies, 1 5/8 primary bbk unequal shorties, 2 1/2" Bassani o/r x pipe, 2 1/2" dynomax catback and a few other assorted bolt ons I dynoed at 210 rwhp and 270lbs of Tq. After i put box stock Edelbrock 6032's, TFS stage 1 cam, ported Cobra intake 76mm maf, 70mm tb, 24# injectors, 190lph fuel pump and a BM elec. fan I dynoed at 283 rwhp and 315lbs of Tq. I ran a best of 13.9 @ 96 mph on the old setup and I've been told i should be abe to hit the high 12's with good driving with the new setup. I'll be dynoing again in a few weeks to see how much help bumping the timing, fuel pressure and some long tubes will help me but I'm told that 300rwhp should be easy with that.

The heads are the biggest and best mods you can make on your motor, but they need alot of support too. You'll need a bigger tb, fuel injectors, fuel pump, adjustable fuel pressure regulator, and you will definitely need some subframe connectors so you don't warp your car when you launch.:D