96-98 Versus 99-02 TwinCam

[82-T/A]

Hey guys,

Is there any difference at all between the 96-98 TwinCam and the 99-02 TwinCam? If so, is there any horsepower difference?
I remember reading / hearing somewhere that the throttle body on the 99-02 TwinCam is larger than the one on the 96-98, is this true?

Is there anything that I can pull off a 99-02 that will give me slightly more power on my 96-98?


Thanks!

[darkfox]

no horsepower difference, at least not rated. Throttle bodies for all years, 96-02, are exactly the same. In fact, 95% of the parts are the same.

the ONLY differences are these:

EGR non-existant on 99+ models. 99+ have a slightly different intake manifold, only difference from previous year models is the absence of the EGR inlet. Exhaust manifold is actually better on the 96-98, having slightly larger runners. Pistions on the 99+ give 9.7:1 compression, up .2 points from 96-98. Not enough to make a difference. Injectors on the 99+ suck, 96-98 have higher flowing injectors. ECM on 99+ is different, but not enough to make a performance difference.

That's about it really. 96-98 motors are better imho, except they are harder for somethings because of the EGR and ECM. (ho intake mani swap and gm charger, etc)

[Lash]

I find it kinda strange that the newer ones tend to run quicker times. I dunno...


I've seen more and more that run 15.2-15.0's with barely anything done. Maybe it;s just me...... or just the better tranny ;)

:)

[SpyhunteR]

I'm going to say it's the tranny's fault.

[darkfox]

maybe i should invest in a 99 z. then again, i theoretically SHOULD be running low 15's, but ihave my gay 4t60e transmission making me slow as poop. of course, woulda shoulda coulda don't count. i can't say poop until i do something crazy like get a tranny swap.

anyone care to swap in a nice new getrag for me?

[SpyhunteR]

I'm also blaming it on myself.

[82-T/A]

Hmm... see, my goal is to one day build up a 98 Grand Am GT with a 5-Speed, the 2.4 TwinCam (built up with the secret cam swap, performance exhaust manifold, and a good port / polish job) and then install the SuperCharger.

I'd like a reasonable 200hp from it. I think it would be a pretty sweet ride. I figure it would be good for mid 14s in the quarter.

[judgez24]

yeah ive got a 9 9motor in my car, with a 97 exhaust manifold, intake manifold and tb, intake manifold has bene ported same with the tb, quad 4 ho injectors in the car aswell and a 97 ecu, soon tobe an ho intake manifold, so we'll se ehow that works for me

[darkfox]

i had the 33lb ho injectors in mine and i swear they made me run rich as @#$@#. what i thought was more power was just the horrible amount of low end torque the rich mixture created. My exhaust tip is still coated in black soot from that.

[AmIGrand]

I'm going to say it's the tranny's fault.

I'm also blaming it on myself.



That's funny, I don't recall ever seeing you beat a stock '98 at the track...? :eek::D:p

[SpyhunteR]

Originally posted by AmIGrand
That's funny, I don't recall ever seeing you beat a stock '98 at the track...? :eek::D:p

you're going to be one of the first 5 people that take a ride in the new grandma in the next few weeks, we'll see what you say than.

[judgez24]

my computer seems to have adjusted for it and im getting stoich readings again, which piss me off, i think i might have some sort of issue with my o2

[Lash]

Originally posted by darkfox
maybe i should invest in a 99 z.

If you get a Z....get a 2000+. It has the better tranny...plus...if you ever do decide to get boost (turbo or S/C)... the reflash does wonders!!!!!! Theres a guy in WI with a 99 that didn't have the reflash with his turbo set-up......he swaped in a 00+ computer/cluster and now he said the thing feels like it came turbo'd from the factory ;)
There a write up on it on .org.

[AmIGrand]

Which Z do you mean, DF? As in, Nissan, or as in Z-24? If it's the Z24, who does reflashes on these things?

[Lash]

A Z-24.... Some people who put the GM S/C on a pre 00 and they can't use the reflash because the computers are different.... so the sell the re-flash part of the kit. Usually you have to take your car to the dealer to have it done unless you have connections ;). The computer allows the car to read boost and adjust for timing and fuel. It also allows you to use a 2 bar map instead of check valves. Makes the car much more boost friendly and also gives a better basline/start in the tuning process.


Thats why Nick (change for a button) swap his computer. I'll post a link...hang on...

[Lash]

here....


http://www.j-body.org/forums/read.php?f=40&i=45434&t=45434


:banana:

[darkfox]

BAH fug da boost i will just get me a bottle of laughing gas and be done with it.

BTW judge what color top injectors are they? blue? brown? green? saw some green ones at the yard... wanted to know if they were worth anything.

[judgez24]

darkfox, i cant remember what color top these are, if i can sneak a peak in there without removing too much ill let you now, all i know is they came from a 92 ho quad in a gtz.

also to the comments about the 2.4's, if you do buy one and plan on moddingit look for a low kid 96 - early 97. my motor is proof they are stronger than the newer ones and i guarantee my 99 motor wont last me more than a year or 2 and its only at 17k while my 97 was at a little over 200k when the ignition fucked up and a plug broke my valve, but in the end the motor still looks perfect other than the missing valve.

there are small difference and you can find them thrughout here and see what they are and for some reason the late 97 and newer 2.4's are weaker and ive seen more of them blown than 96 and 97 motors, ive gota friend with a 98 whos on his third or 4th motor now, i lost count after the last time he broke it and the new motor he had he was having trouble with. theres a guy with a 99 that snapped 3 cranks within 40 k. plus numerous other people woh have had problems and only a handful wreck a 96 - early 97, usually because of misscare of the motor

[Lash]

I've had zero (and I mean ZERO) problems with mine..... I have 64,000 beat to crap miles on it ;).


Only problems I've ever heard of its maybe a spun bearing...but's that cause by driver error. Oh...and then there was that one guy who ran a 12.8 on stock internals w/15psi of boost in 2002 2.4 ;).

[82-T/A]

My 97 Grand Am SE I would beat the piss out of constantly. I even drove it with a failing waterpump for a month. The engine NEVER had any problems until one day when a family member totalled the car at 117k miles. The engine would still start and idle, and I could move it around the block...

But every mile I put on that car, I floored it at least once.

[judgez24]

well my old motor saw more nitrous than you can shake a stick at. hundreds and hundreds of pounds of the shit in good sized doses and i guarantee if i were to replac ethat valve i could get atleast another 60 or 70 thousand km out of her. the bottom end still looks spotless :)