Here is a perfect example of cat-vs-test pipe

[jojo]

Just thought i would share this with you guys, but im sure a lot of you have already experienced it.

I had my test pipe on for the last couple of months, and was running about 24psi of boost 100 octane no problem with 02s right around 750ish screaming through 3rd gear. Took off the test pipe on Friday and put on Random Techs high flow cat, so i could get my car smogged on saturday. it passed no problem. But while driving down to good old Smog Busters, i thought i would open the beast up a little and see what kind of restrictions this bulky hunk of medal would put my car through. Well not to some of you guys suprise, i couldnt get the boost passed 20psi and 02s around 800 or so, and this was with the medal mashed to the floor. Yes!! i lost 4psi of boost and some spool up time, i did not like this at all!! so i went home and put the test pipe back on and, Holy ****!! low and behold boost shot back up to 24-25psi. So i am first hands on witness from experience that a cat does indeed suck for our cars. If you have one get rid of it, you will be as happy as a pig in ****!.

On the other hand, just wondering if it is normal (which im sure it is) from a dead stop at the light, i floor it boost jams up to 21psi, but as im popping through gears, the boost seems to rise up to the final point of about 25psi. Can anyone share the same experiences with this?? or is this called boost creep? if so does it mean anything or is there a way to cure this so boost shoots instantly up to 25psi from dead stop when the pedal is mashed to the floor?

thanks

jojo

 

[blackbuick87]

eventually it may creep past 25psi, keep an eye on it. Boost usually is programmed to go down in 3rd to prevent knock, so keep an eye on that too

 

[jojo]

Originally posted by blackbuick87
eventually it may creep past 25psi, keep an eye on it. Boost usually is programmed to go down in 3rd to prevent knock, so keep an eye on that too

Thanks black, anyone else?

 

[Little6pack]

Well Now I can't wait

can't wait to put my bypass pipe in to see how it works for me.

Hope I get a good feel out of the test pipe

 

[jojo]

Re: Well Now I can't wait

Originally posted by littlesixsteve
can't wait to put my bypass pipe in to see how it works for me.

Hope I get a good feel out of the test pipe

Hey littlesix you wont be dissapointed believe me! i felt the difference hands down buddy. But i also have a 3" downpipe and nice flowing exhaust system, so this whole package makes a difference as well. No back pressure whatsoever. This thing is definately breathing like it is supposed to. Like i said the cat conv.
sucks for our cars, what a wast of performance to even keep one of these things on. Feel the difference and have fun with it

jojo

 

[salvageV6]

Was that the over $200 Random Tech. 3" Hi-Flow cat.?

Just wondering?

 

[scottyb]

See my sig, car basically stock hardware:turbo, IC, injectors, wastegate actuator. The only boost change at the time was done by the already installed RA 93 chip.

Between trips to the track, I installed 2 things: power plate and test pipe, but not in the same day. They say you can "feel" 2 tenths, and I felt it the day I put in the test pipe. At the 1/8 mile track, I gained 5 tenths and 5 MPH!!! The car came alive when I removed the old cat.

 

[TClassic]

Did the NOISE level rise when you removed it???

 

[scottyb]

Yes it did, but I don't consider it to be obnoxious. I'm convinced that my mufflers (installed before I bought the car) are basically useless, but on the other hand I hope they flow well. Another board member said he put on summit $20 cheapies and it's quiet with the same setup. ??? (thread was about drone)

 

[TClassic]

Yea, when I bought this car back in Feb., other than the Exaust, 3" Stainless TH, High flow Cat & ATR Stainless 3" system it was Stock with just the Basic recipe upgrades, but its pretty loud right now with the 3" system, Im afraid that if I GUT this cat It'll be TOO LOUD for me!!! If I DO gut it to test it out, I can't go back!!!

 

[jojo]

Originally posted by salvageV6
Was that the over $200 Random Tech. 3" Hi-Flow cat.?

Just wondering?

Thats the one!

 

[salvageV6]

Ooops, guess my new one goes on Ebay. Maybe I can turn a profit.

I was hoping that it would only lose a pound or maybe two of boost.

Guess not.

 

[Joe 1320]

I was running an open 3" downpipe. Man did that sound sweet! You could really hear the turbo whistle. You may end up having to enlarge the wastegate hole and get a larger puck to control boost creep.

 

[jojo]

Originally posted by Joe 1320
I was running an open 3" downpipe. Man did that sound sweet! You could really hear the turbo whistle. You may end up having to enlarge the wastegate hole and get a larger puck to control boost creep.

Not real familiar with this joe what is all involved with the enlarging the wastegate hole? the puck i have now on my 3" DP is already pretty big.

thanks

jojo