hey guys,

I would like some opinions here. I've got a 90 GTA. 42000 miles automatic L98,hpyertech stage 2 chip, jet fan switch,160 degree thermostat. I also have a complete accel ignition system as well. my exhaust is stock except for no cats but I'm going for a good set of shorty headers and exhaust system soon. My question is, with my mods(including the exhaust) which would you go for first, a turbocharger, a supercharger, or a good set of aluminum heads? Right now I'm leaning towards the heads but I would like to hear from people that's already went one way or another. This is not my daily driver but will be mostly a street car. Anyway I'd like to hear what you think.

 

well it all depends on how time and money u want to invest.installing new heads takes alot of time, plus u need to change the cam to compliment it.and the tpi needs to be tossed then to, youd have to go withsomething else(carb,lt1 intake,aftermarket fuel injection etc).then your going to have to change your converter and rear gears.

OR

just throw in nitrous and call it a day.

dave

 

why would the intake have to go?If he wanted to he could just have everything ported or siamesed.TPI's only real problem is it doesnt breathe enough,so porting,etc. makes up for most of that.

Depending on how much you want to spend is also a consideration.Superchargers are around 3 grand for a set,i think its around their (maybe less if you use junkyard parts)to do a turbo setup,and the heads would probably be a grand for a good set.But like mentioned you really should get a new cam to go with the heads,and do some intake work.

 

I want to keep my tpi though I will probably go with a lt1 intake. I would really like to get a good set of heads and then go supercharged but I can't do it all at once. I just wonder with a tpi intakes known breathing problems would a supercharger really do me much good with no other mods?

 

a supercharger is not really dependent on mods.it will work on a completely stock vehicle.youll gain about 100-130 ish hp.

 

having a turbo or supercharger would overcome the tpi's ability to breathe, but porting or whatever would still greatly enhance performance.


sha-BAM!!!! 200 posts,damned straight :lala: :lala: :lala: :hail:

 

if u bolt on a ati procharger supercharger with intercooler, they say it will make a stock l98 thirdgen run in the mid 12's to mid 13's. I think thats worth around $3,000.

 

Congrats..

Though I would do head work and cam change before adding a turbo or SC. Also some 3:42s and a high stall TC would knock a good chunk off too. The engine will perform much better down the road when you add either of them (turbo/SC).
You're going to need some suspension work soon anyways, all that power won't do a bit of good if you can't put it to the ground.

 

I'm really not too concerned with 1/4 mile times as this is mainly a street car. I just didn't want to waste money on a supercharger if the stock heads and induction would choke it too badly. I'd like to go with an intake, heads and cam upgrade first. Mark, I think the car has 3.42 gears now but I was wondering what kind of stall speed do you think would be best? I do have a new tci streetfigher but I think it's a little to much for a daily driver. Thanks for the suggestions guys and keep em coming.

 

LET ME TELL YA SOMETHING! the last thing ya want to do is siamese those things! it causes a reverse vaccum concentration in the orbital restraint of the intake design. This will in turn casue a pressurization of the soap dish causing your muffler bearings to go on a jello diet! jiggle jiggle!!!!!

 

Originally posted by budda:

<font size="6" color="purple"><b>Oh JOY</b> someone left the door unlocked at the loony bin again.</font> :lala: :lala: :lala: :lala: :lala: :lala: :lala: :lala:


Originally posted by
The bang for the buck is about the same for any of your listed options.
<hr>
Turbo = biggest $$$ = big HP = big bang + difficult install
<hr>
Supercharger = big $$$ = big HP = big bang + moderate install
<hr>
Heads = moderate $$ = moderate HP = moderate bang + moderate install
<hr>
If you got the money go for the big bang.
Heads will give you a nice gain, but not near what a supercharger can. The TPI intake will not be a problem with a supercharger or turbocharger, just crank up the boost to get the flow. You can't do that with heads. There are some cars out there running 9s and 10s and bunches running 11s and 12s with long runner TPI systems with superchargers.
A turbo will give huge gains but are dificult to install.
The heads will give a nice little gain but will be more dependent on the intake and camshaft.

 

Do the basic engine buildup first...intake, exhaust, heads, cam, etc...then get turbo, supercharger, or nitrous for Christmas!

 

Exactly.

 

Keep in mind that the best heads and especially the best cam choice for a naturally aspirated engine will not likely be the best heads and most surely not the best cam for a forced induction engine, and using the best heads and cam for a forced induction engine on a naturally aspirated engine will result in a dissapointingly low HP engine until you install the turbo/supercharger.

 

I like the intake idea alot. I believe the stock heads flow more than the stock intake anyhow (tahts why a superram alone can improve performance). I also really like the ideas of the siamesed runners with the ported plenum. put that together with the SDPC lower for vortec's and maybe some L31's (heads) and a H.O.T.T. cam and maybe a bigger T-body. I think this might be a performer, someone may have the exact or similar system described above and could give us some idea of what this kind of package does.

 

I've always heard that for the time the L98 heads were pretty good, but if I get a set of heads I'll likely get a set of afr aluminum heads. I really like the look of the stock tuned port setup so I don't really want to change it. I'm looking at a cheap used intake to siamese and I thought that the new intake and a good set of headers should hold me over for a while. I'd like to get the heads,cam and supercharger at the same time in order to match the cam.