well after about 10,000 miles my test pipes have cracked open...and now im running a half dump. DO NOT add test pipes or hfc to the nismo...trust me. so what should i do now? put the stock cats back on? trade out exhausts? it's obnoxiously loud and droning now

 

pics of the crack?

its not cause of the nismo i dont see how the nismo would have caused the crack.

 

no pics yet as it just happened while heading to work...the nismo is infamous for cracking test pipes and hfc

 

i still dont see how your exhaust cracked your test pipes... you sure you didnt bottom out any time?

 

im sure...it's been cracked for a month? and suddenly on the highway the exhaust got really loud and immediately i knew what i happened. it just cracked right off.

 

Exhaust didnt crack your TP.

 

what would be the cause then? tons of people have had problems with this setup...cant just be coicidence

 

i have nismo and tps and mine cracked the other day. Only bc AAM tps SUCK!! I want a tp with flex so when im drifting or hittin the gears hard i dont break them due to engine movement

 

I don't understand how the exhaust system (from y-pipe to the rear) could crack the test pipes. I think it is indeed a coincidence.

 

Try the Megan TPs. They have flex pipe.

I've read a ton of Nismo exhausts and cracked TPs.

 

NO It is not a COINCIDENT...many people have reported that nismo cracks TP

 

well i have never experienced this myself, but the cause of the cracking due to the test pipe/nismo exhaust combination could be because of the fact that the nismo exhaust is a single mid-pipe exhaust. therefore the temperatures at the test pipes and y-pipe are increased because of the reduced flow when compared to a true dual.

alternatively, the cause could be strange angling and rigidity between the tps and the nismo (this is pure speculation, i would have to see the set-up in person to make a certain determination). you could follow iStan's advice and get the Megan tps with the flex pipe.

my suggestion is that you replace your stock cats for now; you are dumping tons of unnecessary waste into the atmosphere as well as getting reduced performance from your engine, not to mention you are risking a pretty large ticket if you were to get pulled over for the noise and smoke (depending on where you live). if you buy another set of tps get a true dual, this should solve your cracking issue.

 

you do realize its the same amount as if he still had the test pipes right? and its certainly not TONS. many cars on the road WITH cats dont run as clean. i passed smog no problem w/o cats (im in CA, strictest smog laws in US). thats how clean these cars run

 

Ya, I think im going to put the stock cats back on and possibly sell or trade the nismo for a borla or bassani and possibly add res test pipes. it is unfortunate because this combo was pure audible bliss just a shame

 

Members often report test pipe and NISMO exhaust problems.

But we have no way of verifying that the NISMO exhaust is more apt to cause test pipe problems than other exhausts. It may simply be the the NISMO is a popular exhaust therefor the high number of test pipe problems.

 

^^ +1

I know somebody who had test pipes on his stock exhaust and they cracked. That is not sufficient justification for everyone to go around saying "if you pair test pipes with your stock exhaust they will crack."

 

not at all. all of the exhaust that is leaking from the holes in his test pipes are not going through the rest of the exhaust or rear cat converters, therefore releasing a shizload of unburned hydrocarbons into the atmosphere. i am all for test pipes and large exhausts but there is no reason to unnecessarily pollute the environment.

 

Dude, WTF are you talking about?

please point out where the "rear cat converters" on a Z are. He has TEST PIPES. What leaves the exhaust manifolds is the same as what would exit at the exhaust tips on his setup.

 

woah, no need to be rude. i am not trying to be hostile bro. as i understand it, the 2 rear canisters of the nismo exhaust are cat converters (as well as mufflers)? am i wrong? i know my old hondas had cats on the down pipe as well as in the rear canister. i am pretty confident that those canisters aren't just resonators...

 

I do not intend to be rude, but you have 61 posts here and two of them rank among the stupidest things I've ever seen posted on this forum.

There are two cats on a stock Z, one off each manifold and before the Y pipe. Test pipes replace those. There are no cats in any off the shelf aftermarket exhaust system, to include the Nismo, made for the Z.