I'm considering modding my 1990.

I want more power on the street as well as mannerable on the highway. I've been looking at catback exhaust systems however it seems I can't use the Corsa Pacecar or Touring systems on my car. What direction should I go for a catback sys?

I have no experience building a motor so I have no idea what kinda of rebuild I'm gonna require, can you help me? I have 57K on the odo and it's an automatic.
:nopity

 

I think it all depends on how much you want to spend. For a reasonable cat back system ($500 or so) I think many L98 users like the hooker system and the magnaflow. I can't really recall anyone complaining about either of these. Some systems like the B&B or Power Effects are around $1000! Too much in my book but the adjustability of the PE is tempting and everyone that has this system loves the big block sound. And the magnaflow system looks so sweet. From what I gather headers will make a much larger impact on performance but the sound probably won't be as nice if you just have stock mufflers.

 

I would go Power Effects, but thats still expensive.
Only cheaper one i would do is Flowmasters.

You dont need a rebuild with only 57K, run the sh** out of it, then dig in that motor.

 

57k? Keep that thing for a while. The bottom end should still be like new. I used muffler elims on mine. I couldnt stomach paying $500 for a catback when I could do it myself for under $100 and take weight off the car too.

 

b&b triflos sound mean on an L98

 

COME NOW CF MEMBER's....
I'm a neophyte when it comes to mod's and performance, and for jeez sakes, this is the Tech/Performance forum....put down some knowledge for me and tell me what I should do to make that firebreathing dragon non supercharged/NOS...TPI L98 motor....it's clear go exhaust route...headers lend more power gain at this stage than the cat back system...What else...I'm eager to know the engine mods to think about...

Thanks you gentlemen for your kind support!

ttt :smash:

 

Do they ever! :D :D :D

Ivory90,

a cat back exhaust was the most recent thing I've installed on my car and after a return run to the dragstrip I didn't gain any real improvement in my ET or trap speed. It sounds better though.

To wake your car up a little for a low investemnt do the basics first. If local laws allow it, dropping the precats will give you a noticeable difference. I found that doing a tuneup (plugs, leads, rotor, check timing, new fuel filter, etc gave me a good improvement).

I would do a throttle body coolant bypass, loose the precats (or better yet get headers), port out the plenum (at least get rid of the bumps in the entry to the manifold, relocate the manifold air temperature sensor to the front airbox, install a lower temp thermostat and fan switch to kick in the fans earlier, and maybe add a K&N as first mods. These shouldn't be dead money if or when you get more serious later.

An adjustable fuel pressure regulator is not easy bolt on HP as it only has an effect under WOT, the rest of the time the ECM cuts back on injector "firing" time to keep things within set parameters. This would be a mod best setup on a dyno IMO. When I installed one (without dyno tuning) I couldn't feel any difference but I did notice an increase in fuel economy.

If you don't know how to do these mods, do a search in the archives or post a thread and ask.

One other thing, if you replace the lower intake manifold later for an accel or edelbrock don't bother unless you install larger runners as well.

As far as exhausts go, any C4 system can be made to fit your car, it just requires more fabrication work. We have more than a few L98 guys on tthis board running LT1 cat back exhaust systems on their cars.


[Modified by Red 90 L98 Coupe, 1:25 PM 6/30/2002]

 

There are quite a few cars here with bolt on mods running low 13's-high 12's. Search for Vic 89, 65Z01, and my car to see what a few bolt ons do. Check out L98 Terror's car and Scorp's car and you can see what lots of bolt ons do for an L98.

 

Frank,

I always advise those who are about to start mods to their Vettes, to do so only after you have laid out a plan.
Don't buy parts just to buy parts. Combinations are so very important. Some work, some don't.
A question you must ask yourself is: Where do I want to be 3 to 5 years from now? Will I still own this car? Do I need to spend the dollars on mods,
since I plan on buying a newer Vette a few years from now? I would say it depends on how 'deep' your pockets are.
I've always tried to 'budget' myself, by only spending around $1500 a year
on parts. This way I put pressure on myself to plan all my modifications
very carefully, and not spend money fullishly.

Review the numerous signatures of other '90 Vette owners.
See what works for them, and what hasn't in the past. Take notes of their numbers. E-mail those owners. I think you'll find everyone to be up front with you about their successes and failures. I think it's safe to say, anyone who posts here on the forum, have a great amount of pride about their Vettes, and the imformation they supply. And that's a good thing.

If you must get started in doing the mods to your Vette...your first purchase should be a 3" notebook binder, and 3 hole punch from Office Depot. I'm not kidding. If you're going to get into it, you must keep accurate records of all your purchases.

Plan, plan, plan.

Good Luck,

John

 

Thank you gentlemen for the informative post!

Frank :seeya

 

Just remember... the little things make a big difference too!