performance questions

**racingrev** · 10-06-2008, 11:07 AM

Fairly new on this camaro thing. I just got a 1999 SS convertible. Came with a few upgrades. SLP center mount exhaust, SLP airbox, smooth bellows, shorty headers and msd plugs wires and coil paks. Was told by another fbody owner that I should get rid of the cat converter, air pump and O2 sensors as they are restricting power. Is this true?

If I did that wouldn't that mess up the computer and cause the car to run poorly?

Really appreciate any one who has some more experience commenting!

Thanks.

**konigandy6** · 10-06-2008, 11:39 AM

Originally Posted by racingrev

Fairly new on this camaro thing. I just got a 1999 SS convertible. Came with a few upgrades. SLP center mount exhaust, SLP airbox, smooth bellows, shorty headers and msd plugs wires and coil paks. Was told by another fbody owner that I should get rid of the cat converter, air pump and O2 sensors as they are restricting power. Is this true?

If I did that wouldn't that mess up the computer and cause the car to run poorly?

Really appreciate any one who has some more experience commenting!

Thanks.

Yes, the air pump and converters are robbing horsepower, and yes your car would run a little rough if you just rip them off. You are going to have to invest in a good computer tune for your vehicle, so the A/F ratio can be programmed in as well as your emmissions SES codes programmed out. Otherwise your SES light will pop on and stay on no matter what.

Also, IMO, invest in a set of long tube headers and ditch the shorties. You will be much more impressed.

**Mr. Hyde** · 10-06-2008, 12:12 PM

The advice on ditching the shorties is good, no great advice. You'll notice a huge differance right away. As far as O2 sensors limiting, or restricting power, not so, actually the front set is NEEDED by your ECU to keep your car properly running. The rear set is there to let your ECU know if your cats are working properly, if you ditch the cats, you'll need to let your ECU know about it, or run "Sims", otherwise that dreaded SES light will be on.
I've never experimented with any of those "handheld" tuning devices, although I'm sure they are up to the simpler tasks. Like many serious modders, I have a tuner, he did quite a bit of work on the SS Camaro, and he has had his hand up my Z06's skirt already!
My advice would be to seek out a reputable tuner, and turn him loose on your car, he will bring out the max HP and drivability that's in your car.
P.S.You'd be surprised at all the stuff they can do once they're in there too...
If you have a M6 he can eliminate the "skip-shift" feature, calm down the traction control, so it doesn't kick your foot off the gas pedal, and of course, turn off those rear O2 sensors! Just a few small examples of what a tuner can do in there in addition to the obvious of make your car run much better!

**67CamaroRSSS** · 10-06-2008, 12:55 PM

1st off, are you subject to any kind of smog check? If not then you're good to go.

Discalimer: Neither myself nor the owners of this site recommend any alteration of any pollution control device of any automobile being used on any public road.

Ok, with that out of the way here are some "theoritical" things you can do to increase the grunt of your engine.

If you are going to race your car then you'll need some alterations to the chassis:
1 - Sub frame connectors to tie the front and rear together and also to stiffen it up.
2 - Adjustable torque arm. Stronger than the weak factory stamping and adjustable for pinion angle.
3 - Other changes based on application. Road racing will be a different setup than 1/4 mile acceleration.

Long tube headers and a good true dual setup will benefit any engine. Delete the cats. The front O2's must remain as this is what the ECU uses to determine A/F ratio.

If A4 step up to 3.73's; if M6 step up to 4.10's. These gears sets are an ideal compromise between acceleration and high speed cruise.

Tires, tires, tires! Your street tires are good for the street, not drag racing, not drifting, not slalom work nor will they work well on a road course.

If A4 get a high stall converter. If M6 a better clutch and a better rear end are definitely in your future.

Get a dyno tune using the services of a professional tuner! I can't stress this enough. If they don't have HP Tuners (preferred) or LS1 edit then I'd be suspect.

There are a lot more things than this but I haven't the time right now to write the book.

**c5z28** · 10-06-2008, 02:50 PM

If you have smog laws in Canada, and you want to stick to your shorties leave the o2's and cats, on, the power gain is not much and the o2 sensors help your car figure out if it is running to rich/lean giving you the best performance. If you do decide to go long tubes, get the ones with the air pump provisons and cats will only cost you an extra 300 if that. I took off my smog stuff here in Cali and it can be a bitch sometimes dealing with the government if I had to do it over again i'd stick with the cats and o2's.

**racingrev** · 10-06-2008, 08:23 PM

Thanks for the pointers! I will hafta look into cost on the long tubes.

**racingrev** · 10-06-2008, 08:26 PM

Also have been thinking about once i am done adjusting the exhaust sending the PCM to LSX for that tune you are all stressing the importance of. I am not sure about a tuner near where i live...

**c5z28** · 10-06-2008, 11:16 PM

Your only going to need a tune when you put on headers, swap intake manifolds, cams etc, even then your car's computer will run in "safe" mode and run rich, so your car won't lean out and blow a cylinder on you. If you can't find a tuner you can get a mail order tune not the best but better than having nothing. Also you won't need a tune by having shorties and changing exhaust, unfortunatley shorties don't net much of a power gain if any, they just weigh less and look better, as for exhaust it only makes the car sound better. Have fun

**Insert** · 10-07-2008, 04:30 PM

just do whatever you like and dont worry about smog laws. i have "heard" from some guys talking on some street corner that it is really easy to get around the emissions tests.

on an unrelated note, i had my cats pulled and a true dual setup, and but i had it made to accomodate the stock CME tip, (which IMO looks amazing) and my car passed all emissions tests.

where abouts are you in canada?
Ontario maybe? in the GTA area?