Hi everyone,
My name is matt. I'm new here and hoping you guys can lend some advice.
I have a 350TPI out of an 89 TransAM GTA. I want to add some low end HP to it, make it quicker off the line. IM currently running 13.30 @ 104, id like to get it down to the low 12's.

I already know that the best solution is an easy flow exhaust... that’s not really an option as My set up requires a pair of Sanderson CC90 headers (shorty block huggers). So what other options do I have?

I’m going to be getting a set of side scoops, so that I can have better air access for the air intake... but other then that I’m out of ideas.

The engine only has 50k miles on it... most of that is track time (from the previous 2 owners). Its never been someone’s daily driver... tell me.

So any advice would be great. Thanks guys.

 

By low end HP, I assume you dually mean torque. If you setup is using the stock runners and baseplate, there's not much more low end you will get outside of bumping up the timing to around 8 or MAYBE 10 degrees if it's not already there.

I never knew those Tuned Port Fiero's to be low 13 second cars, but if you are looking to improve that - I'd look into a new baseplate (I feel Accel is the best while Edelbrock's has a shakey reputation), and a set of modded SLP runners. With your rather low vehicle weight, I think more high end power would be beneficial. If a SuperRam is affordable to you, go with that. If you have no emission's concerns, I see no reason not to go with an LT1 intake, or a HSR if it will fit. Do you have any information about your engine? Cam Card, Heads, Compression Ratio, etc?

Lastly, out of morbid curiosity, what is the top speed of a little aerodynamic car like that with a V8 and a 5 speed? I've always wanted to do an LT1/Fiero but wouldn't do it with the isuzu 5 speed, or an auto/4speed which is all that is easily found around here.

 

By low end HP I mean, HP at slower speeds to help me off the line faster... so yes I guess torque... Stock the 350 has I believe 330... somewhere in that area.

Well, i believe that the stock trans am gta ran the quarter mile in the low 14's... put that same engine in a car that’s over a 1k lbs less, and you’ll cut a full sec off that time... I only want to improve on the time, because there’s a kid at work with a mustang running 12.5 in the quarter (ive seen his time slip), and he doesn’t think the Fiero could ever do it, and I must prove him wrong.

I haven’t reached top speed yet. My Speedo only goes to 80, I’m looking for a 120 gauge, and then I may have to get a larger one after that. I have tried to get an idea, I drove along side my friend in his vette, and up to 130 (where he wanted to slow down because he was scared) is the fastest ive gone... I was in 5th gear at 3900rpm... I know I could have gone to at least 156... most Fieros at that speed would have been shaking, but I have a new front and rear end suspension, cost me over 2k grand but it was worth it... I can now out handle an 88 Fiero...

 

It's pretty hard to beat an L98 off the line with *more* parts. You'll go faster in the quarter with fully functioning stock parts, plus some more flow, like a bigger cam, and intake base and runners - with a matched up plenum, then heads. You're stuck with exhuast, and have a manual tranny. Traction should be your problem, not torque. Toss a scantool on there and see if you're hitting lots of knock (and knock retard), then determine if it's real knock.

 

Welcome from another PFF'er. I'm Kissmyssfiero over there.

I'm somewhat familiar with your car. i was going to buy it before you did, but decided I'd better finish mine instead.

If I'm not mistaken, You have a centerforce clutch. IMO, you're about at the limit of what that clutch will handle. Get a spec stage 3 if you want to up the power.

Like said above, you'll need bigger runners and an intake. Thats a good start.

when you want more, dig into the motor. Ditch the stock cam. Then the heads. That should really bring down your ET's.
With all these upgrades, you need to upgrade things like your injectors, fuel pump, etc. Like you would any engine.

If you ever rebuild the motor. up the compression. Forged internals would be nice for reliability.

Driver skill is also important. Practice at the track. I have rodneydickmans sport shifter on my car. Not a short shift ****, but brackets and linkage that shortens the shifter throw. It takes about an inch out of the stock shifter throw. I love it. I barely move the shift **** to change gears with no noticable increase in shift effort. I think its about $125.

You could also run a HSR. Thats what I have on mine. But be prepared to cut up the decklid. its Tall.
Here's a pic I just took of mine. If you have any other questions, PM me on here or at PFF. I'm glad to help.

 

Bet that takes a pretty impressive shoehorn to fit in there.

 

How are spark plug changes?

 

That's a pretty wild statement with the extra weight in the a$$.

 

Theyre easy... but thats only because I have access to a lift.



It's an extra 35lbs. Not nearly enough to make a difference, and if it was it doesnt matter, I have my battery relocated up front.
Soon Ill have an amp right next to the battery... That should help in that department as well.

 

I'd say its closer to 75-100lbs difference. Considering a stock auto trans weighs 50lbs more than a manual, it's hardly a negligible difference. I feel no difference with the added weight. The torque difference is very noticable though. Hard to keep the skinny 225's hooked up. And this car has suprisingly good traction. All the weight of the engine is over the tires.

You can't outhandle an 88 fiero with the same upgrades. I have one(an 88), I've driven and owned both. Stock and modified.

Plug changes aren't that difficult. Only the #1 plug is hard because the alternator is close. I could remove the alternator in about 15 minutes if I had trouble with the #1 plug. I haven't changed plugs yet, but I did look to see how hard it would be. I only pulled the #4 to find TDC while setting the timing. I would pull the plugs from underneath. I could probably do it in 20 minutes.

 

You guys have sparked my interest. Those have to be sick cars, even with a mild 350. What do they weigh? How hard is it to find a decent one? I've looked on ebay but did'nt see anything close to me.

 

I think they only made a few hundred thousand of them.....

Finding one with the right combination (in my mind), without the front end rotted out here in Ohio was so difficult that I gave up after a year and a half. There are lots of 4 spd cars out there, lots of auto's.... but 5spd v6's (what I wanted) and getrag 5spd instead of the isuzu 5 spd was very, very very hard to find for a decent price in decent condition....

I you don't care about overdrive, or base engine size, finding one in good shape is easy.

 

Goy they didn’t make any, the v-8 was not a factory option, all v-8s are decedents of either a Zumalt kit (mine) or a Archie kit. Both have their strengths and weaknesses.

I live in MI and it wasn’t too hard to find a V-8 with out a rotted front end... the trick is finding a guy who cared about his car... my Fiero has no rust on it... even my exhaust has no rust and the v-8 conversion is 10 years old.

GMGod id suggest trying Fiero.nl that’s and enthusiast site. There are lots of people there who have v-8s for sale... or stocks in great shape for sale, for only a couple of grand you can make your own v-8. Good hunting... and welcome to the dark side.

The best part about a V-8 Fiero is that no one ever thinks its gonna be quick or fast… I mean they know that the Firebird is gonna be good… but a Fiero… na, and then you show them… and they have to think twice next time they see ya… the look on their faces is always worth it.

 

Don't they notice the strange sound?
As for your question, if I were you I think I would do a vortec head/vortec stealthram swap. I may be telling you somthing you already know but the heads/cam/intake are not really performance peices on these engines, but it does'nt look like you can swap cams with the engine in the car. Don't worry about the tiny loss (if any) in off idle torque, you won't miss it.

 

Oh yea, I would guess that would get you about a 12.8 at 109mph with 1.6 rockers and a good tune.

 

I said I was looking for a 6cyl/Getrag 5spd, which they did make. Maybe you missed this impotant part of my post...
I highly doubt anyone actually thought they came factory with any v8... but too assume I did would make me want to slap you.

 

Back to the origional post! I fabricated an exhaust for a guy here in Windsor that converted his fiero to an 8. We ran the hedman block huggers ( pretty much the same as your sandersons) and I used two dynomax bullet mufflers (it doesn't resemble anything quiet!!) due to the space restraints. If I was to make that exhaust again now, I would use two flowmaster hushpower's instead. Anyway, Low end performance in your case shouldn't be much of an issue. You should have more than enough grunt to get that fiero moving. You could try going to a little shorter tire to help lower the final gear ratio. That would help get you moving. I Like the idea of the stealthram to make more power higher in the rpm range. My biggest concern in your quest to the 12's (?) is, will that getrag handle the abuse of that kind of torque in a manually shifted car? If it can't handle it then where do you go from there? There isn't alot of options for a transmission for your fiero! Good luck with your project.

 

Sorry goy my mistake.

Ya... theres a Tranny that im supposed to use when I have higher toruqe... I forget off the top... ill find out. that would be step two if my tranny went.

 

Are any of the automatics in those cars overdrive?

 

No. If you did the 3800S/C swap you can use the 4t60 (4t80?) out of that.