New Car 1991 TT - rotted exhaust

[RedZed]

Hey Guys - I am new to the forum, this is my first post. I recently picked up a 1991 300zx TT for 8k with 70k miles on it. Its been under a car cover and maintenance has been somewhat neglected ( I changed the oil and the filter had a date of 2011 on it.) The Cat Back exhaust is also rotted out. It looks like a local muffler shop job and not a high end exhaust.

I have limited access to a lift and am thinking of just doing downpipes and test pipes right away in addition to the cat back exhaust while the vehicle is on the lift. 3 questions....

1. I am thinking of HKS exhaust and megan downpipes. However to me mixing exhaust parts from different companies might not make sense from a flow standpoint so in that case what are your thoughts on the PG system? I have a limited budget so I think the specialty Z system is out of the question

2. Do I need an 02 sensor check engine light eliminator?

3. It looks like there are additional pipes going to the exhaust around cat. I read that Nissan does this to pump clean air into the exhaust. what do I do with this portion of the system?

thanks for the help, looking forward to being a member of the community.

[Ace2cool]

1. Mix and match doesn't really affect flow too much. As long as the diameter is the same, it should all flow the same, depending on bends, ect. But as far as mating the pieces together, mixing isn't gonna affect performance. I'm using Z1 test pipes and H pipe, AMS downpipes, and SZ axle back.

2. No. You'll keep the only 2 O2 sensors you have, as those are for the ECU, but pre-96 Z's didn't have the "post-cat" O2 sensors.

3. AIV's can be deleted. Go into the fender wells and start ripping s*** out.

[RedZed]

awesome thank you very much.

[RedZed]

I wanted to follow up on this post. I got a great deal on some new/used stuff

z1 2.5 inch downpipes
z1 2.5 inch test pipes
SZ 2.5 catback with resonators.

now I just gotta talk to my mechanic buddies about using their lift so I can pull the transmission and get the DP's installed along with the rest of the system.

[NolimitZ32]

Any particular reason you are pulling the trans? It can stay in place to do downpipes, and personally its more of a hassle to pull the trans just to do the DPs.

[RedZed]

Everything I have read indicate that I need to pull the trans or the motor to get at the underside of the turbos to swap the DP's if that is not correct that is a good thing. I admit I havent crawled under there and looked yet. I am a new 300zx owner so I have a great deal to learn.

[NolimitZ32]

Pulling the turbo requires the removal of the engine or a head because you physically cant get to the engine side nuts but getting the down-pipes off requires a couple different angled shorty box-heads, a ton of patience, and a rich vocabulary of curse words. The hardest part of it all is that the nuts and studs are likely rusted solid so before going at it you need to spray it down with penetrating fluid at least a couple days before and let it sit. Other that that it IS possible to get them out without dropping the trans.