I have my new 91' TT 2+0 in for the 120k service and the Tech noticed a hole in what he described as the "part with the rear cats in it"/ "pipe that hooks to the front down pipes". I'm still working with him to figure out the exact piece that needs replacing, but is anyone running these Z1 pipes on their car and/or have a recommendation? The OEM pieces are priced pretty steep.

https://www.z1motorsports.com/exhaust/z ... -5406.html

Thanks!

While I can't testify to any of these replacements, as I still have the factory mid-pipes installed, they are on my list to be swapped out. I'll be going with test pipes as part of the AIV delete - helps that we're not subject to emissions here in Franklin Co., PA (I'll probably be going with Specialty Z test pipes). If you don't have this delete done, you'll need to be careful to order the pipes with the inlets for the air tubes... or just do the delete:

http://www.twinturbo.info/63104/137858.html

It looks like the Z1 pipes have them, but I'd recommend calling and talking to someone live to discuss as oppose to a blind internet order. If the person you speak to doesn't instill confidence, hang up and call back later. I've had the best luck calling early in the morning, before the day gets busy.

Again, I'm a relatively new Z owner (got my '91 TT in June), so I'd also wait to see what those who have many more years, dollars, blood, etc. invested have to say.

Thanks, that's good to know about the AIV. This Z is my first performance car - and this is the first time I've had any work done since I picked it up about a month ago - so I'm on a steep learning curve. It doesn't help matters that the first owner had an aftermarket cat-back put on over 15 years ago but I have no idea who made it.

I do know the pipes are 2.5", so that's a start. I'm hoping a couple pictures from shop and a phone call with Z1 can help clear things up so I don't order the wrong piece.

I believe the first owner also installed a Jim Wolf ECU, so I wonder if the AIV delete has already been done or would be a good idea anyway.

I recommend taking it to a Z specialist. Unless your mechanic has experience with them, you risk pulling the pin on the grenade. This is especially so if you’re unsure of what’s been done. I have no idea who is in NC, but Bernie Bilski is in Alexandria, VA - he’s essentially the east coast expert. You can look him up on twinturbo.net.

Robo’s site that I linked above is an excellent source, as is here and twinturbo.net. Also download a copy of the Factory Service Manual that’s linked in the “All you need to know...” sticky.

Thanks, that Factory Service Manual will be a huge help.

Bernie sounds like the east coast Mecca for Z's, but with work and some other responsibilities on the weekends I needed to stick closer to home right now to get the car running right. I took her over to Jeff Underwood at Nisstech Imports here in Indian Trail, NC close to Charlotte. He's a Nissan Master Tech and now runs a shop specializing in Nissan/Infiniti and has past experience with Zs - recommended by the local Carolina Z Club.

I just picked her up yesterday with the timing belt service done, a couple new fuel injectors, and a Red Line Mt-90 change, and she's running much better than before and shifting as smooth as a 288k miles original transmission can (that'll be another project later on). After talking with Jeff and figuring out where the hole was in the exhaust, I called John at Z1 and ordered the 2.5" Z1 High Flow Cats. Looking forward to getting those delivered and bolted on in the next few days!

Awesome that you have a local guy who knows the Z. I don't have the luxury here in south-central PA (Bernie is a few hours away), but my intentions all along were to do everything myself anyway. That being said, I plan on keeping the car relatively tame. After some maintenance tasks and deletes to clean things up and reduce potential issues, I'll ultimately look to push up into the 14-16psi range. Barring a turbo failure, I have no plans above that... gee, I sure hope I didn't jinx myself just now

Ha! Knock on wood.

I'm hesitant to push the turbos, or anything else really, with 288k+ on the odometer. I'm told the first owner replaced the block a while back and everything else is stock/OEM to my knowledge other than the unidentified cat-back, the Jim Wolf chip, and some PowerStop brakes.

Now with the 120k service done, all cylinders firing, and exhaust soon to be good to go, I'm hoping to get by on just oil changes and tires for the next couple of years until I can get a house/garage to start really getting my hands dirty.

Although I do like the idea of the 98-spec trans at Z1 or a rebuild... The mT-90 helps, but my synchros have lived a long life.

Well transmissions are usually 300-350..pretty cheap so I owuldn't worry, unless you're dogging the piss out of it the trans should be fine..if its fine right now