figured my problem out
Thread Starter
Racer
Joined: Jan 2014
Posts: 288
Likes: 10
From: Proctor WV
figured my problem out
Junk out of pre CAT
Inlet
Pulled the whole system off. Chunks laying in front of Main converter on my 86. 1 Pre cat toast.Other OK, Gutting the whole system, No smog checks in WV......Straight down pipe before main CAT sounded good ...Gutting my main CAT, reinstalling with Magnaflow rear pipes. Got my motor back....Been running like crap couple of years....Got my Problem solved
Drifting
Joined: Oct 2015
Posts: 1,674
Likes: 191
From: Shit Creek, USA
Good luck and congrats.
Zen Vet Master Level VII
Joined: Mar 2016
Posts: 5,218
Likes: 1,174
From: Southlake, TX
Me too.
I took off the precats and then put on a performance catalytic converter and left the factory mufflers. WOW. The car sounds great and you can feel the difference.
My muffler guy suggested this mod as he says he has been doing it for years on the L98. He said the pre cats are very restrictive and really don't do anything. He suggested the performance cat (with air bung) as he said that it will flow 6x better than originals.
I'm very happy with the way it turned out.
Thread Starter
Racer
Joined: Jan 2014
Posts: 288
Likes: 10
From: Proctor WV
78000 miles on my 86. The main cat was changed before I bought it. ( it looked newer) The front screen on the main cat caught all the debris luckily. But I have material loose in the main cat, nothing got past the rear screen into the mufflers
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Drifting
Joined: Oct 2015
Posts: 1,674
Likes: 191
From: Shit Creek, USA
Zen Vet Master Level VII
Joined: Mar 2016
Posts: 5,218
Likes: 1,174
From: Southlake, TX
Drifting
Joined: Oct 2015
Posts: 1,674
Likes: 191
From: Shit Creek, USA
Does someone offer bolt in straight pipes?
Zen Vet Master Level VII
Joined: Mar 2016
Posts: 5,218
Likes: 1,174
From: Southlake, TX
I don't weld either. I took it to a shop and they charged me $75 and they were done in 45 minutes.
Can't help you on straight pipes from the header, but I bet the parts suppliers will have them. I worry that they will cost more than a cut and paste job....
Can't help you on straight pipes from the header, but I bet the parts suppliers will have them. I worry that they will cost more than a cut and paste job....
Drifting
Joined: Mar 2011
Posts: 1,693
Likes: 144
From: on Barnegat Bay Joisey
[QUOTE=billschroeder5842;159559245
Can't help you on straight pipes from the header, but I bet the parts suppliers will have them. I worry that they will cost more than a cut and paste job....[/QUOTE]
Replaced the front Y pipe for one without precats. Billy's right, it cost about $150+install.
Can't help you on straight pipes from the header, but I bet the parts suppliers will have them. I worry that they will cost more than a cut and paste job....[/QUOTE]
Replaced the front Y pipe for one without precats. Billy's right, it cost about $150+install.
Zen Vet Master Level VII
Joined: Mar 2016
Posts: 5,218
Likes: 1,174
From: Southlake, TX
LOTS
I removed my precats and installed a performance catalysis and kept the factory mufflers. I was able to feel an immediate, no Sh*t difference.
Everyone asks "how much HP increase ??" I have no clue; only the SOTP Dyno for me.
Budget allowing please remove the pre cats and the catalysis. They both are super restrictive
I removed my precats and installed a performance catalysis and kept the factory mufflers. I was able to feel an immediate, no Sh*t difference.
Everyone asks "how much HP increase ??" I have no clue; only the SOTP Dyno for me.
Budget allowing please remove the pre cats and the catalysis. They both are super restrictive
Melting Slicks
Joined: Oct 2016
Posts: 2,024
Likes: 363
From: Central Alabama
Interesting. What is the intended purpose of the precats?
My 2001 MR2 has precats. Toyota used them to get a lower emission rating. They only serve a purpose during main cat warm up. On the MR2 they are Known to break up and can get sucked into the engine. Thus gutting them is pretty much standard.
I know that sounds odd but Toyota used their Variable Valve timing for EGR. When they want to draw exhaust back they delay exhaust valve closing into the intake stroke.
My 2001 MR2 has precats. Toyota used them to get a lower emission rating. They only serve a purpose during main cat warm up. On the MR2 they are Known to break up and can get sucked into the engine. Thus gutting them is pretty much standard.
I know that sounds odd but Toyota used their Variable Valve timing for EGR. When they want to draw exhaust back they delay exhaust valve closing into the intake stroke.
Tech Contributor
Joined: Aug 2006
Posts: 9,933
Likes: 103
From: Peoria Arizona.. Resident Gold Cylon
Junk out of pre CAT
Inlet
Pulled the whole system off. Chunks laying in front of Main converter on my 86. 1 Pre cat toast.Other OK, Gutting the whole system, No smog checks in WV......Straight down pipe before main CAT sounded good ...Gutting my main CAT, reinstalling with Magnaflow rear pipes. Got my motor back....Been running like crap couple of years....Got my Problem solved