Help. Car taking a nosedive on power...

[Pewter2K1]

Well to start, the car is a 2001 Automatic with right about 96K miles on it.

I have a Comp cam 210/220/.512/.512 @115. Magnaflow 3" system w/cutout. 3" ungutted cat, stock tubular manifolds. 3.42 gears, Lid, Taylor wires, NGK Tr55 plugs.


Heres the deal. Last March-may 2004 when i was running the car N/A after the cam swap it was consistently in the 14.6-14.70 range with 2.1 60's on a decent day. Not optimum weather at all. Over the summer june-september was my nitrous kick. Running 13.30 and still like 14.65 on motor. Well a year went by and the car never made it back to the track, and over the winter nothing was added to the car but a set of pushrods and a good cleaning out of the heads, no porting, just removed as much carbon deposits as possible. Raced the car again this year and it was running worse than stock times (15.0). The best i could get was a 15.2@87. 60's were 2.2's. I got a code on the way back that the O2 was bad, so i replaced both front sensors, and also did the !knock sensor mod. Went back and still running the same. Was able to squeeze a 15.0@88 with 2.25 60'. I am NOT spinning, launching the car at around 2K. I am puzzled, the weather wasnt great at all, mid 90s with humidity, but i wouldnt think its enough to take almost .7 seconds off the time.

So now i am at school, car is home in the garage, and I am tryin to make a list of things to check, change or upgrade when i return for breaks.

I want to do a compression check, thinking maybe the nitrous caused the rings to go out a bit.. or maybe a bad valve seal.

Also thinking maybe the cat is clogged... car runs rich, i know that, but it is as rich as it was when i was running 14.60s so...

Transmission slipping.... 96K on the car 76K on the tranny, and i have not been nice to it at all


Maybe i just need better weather..... I am at a loss... if anyone has any imput to what I should look into would be greatly appreciated. I dont want to tear too much into it, but if need be I will at least get the heads off and send them away for a valve job and a port.... but now I am just mainly concerned on getting it back to previous times, not go any faster than before... just incase thers somthing serious that would be worsened by more gofast parts.


Sorry for the long post, but gots to get all that info in there.

[AZ3.8Camaro]

I used to run 16.2s in the AZ heat stock.
Got it down to some 15.9s with practice.
Then did the cam. Ran some 15.8s and 15.7s, was very dissapointed.
Replaced the cat and ran a 15.0 the first time out.
The car will easily do mid 14's na on a good tire, with the new gears, but I don't have the time to race it.

Moral of the story is: Replace the cat.

[98 3.8]

How many miles did you have when you replaced your cat, AZ?

[ChronoGN]

Just take off the cat.

[slow6]

gut it
maybe your cat was clogged?

[AZ3.8Camaro]

Don't gut it. It pollutes more, makes your car sound terrible, and I ran no better time gutted than with a carsound 3inch highflow cat.
I got a highflow cat, was so impressed with the results that I got greedy and gutted it. It sucked, and was no faster. I then paid again for a new high flow one. Couldn't be happier.

It had 65K or so on it. I had the cam for 10K of those. My valve seals went out, and I was burning oil for about 2K of that, which couldn't have helped.

Bottom line, replace it if you doubt it.

[Pewter2K1]

yea, cat is gonna be the first thing on the list... Carsoud is the way to go? No Cat-co.... have a part number for the carsound cat?? THanks

[Tyler]

caugh !Cat Caugh!

How is emissions in Va?

[Pewter2K1]

no emmissions yet, but i think its on its way, and i think i would rather go with a quality high flow than just a gutted 3"

[articacid]

if you not sure if its the cat or not and your going to by a new one anyway, i would just gut it 1st to see if that is indeed your problem.

[pgriffith]

Catco makes a very nice high flow cat. I picked one up from summit for all of $50. Then another $10 to have it welded on.

[AZ3.8Camaro]

Yeah I think most companies are similar for highflow cats. Catco or carsound. Just a a 3inch in inch out, with no air pump provisions. They might be a little shorter than stock, but you can get a 3" section of pipe to add in.

I felt kind of redneck with it gutted and it sounded like ***. Thats just my opinion.

[Pewter2K1]

Yea new pipes from cat to muffler are on order, 3" Carsound, 3" Ubend for S-pipe, and new 3" straight pipe to allow for a clean transition to the over the axle pipe. Should have it on when i get home from school for a long weekend in October. Probably will get back to the track on thankgiving break tho... oh well, its well needed and is a good start. Its the first on the list but was the last to change...
So besides the cat... anything else i should be looking towards??

[AZ3.8Camaro]

Id still do that compression test, for the hell of it.

[Pewter2K1]

anyone know what i should be reading for a "proper" compression?