pureZero

Just took about half of the sound deadening material out of the floor boards and tunnel... I'm finding that it isn't much easier to use dry ice than the heat gun I have. Either way, it isn't an enviable chore... There's a bit of cancer on the driver side floor pan, and I managed to see some daylight coming through the passenger rocker panel. Passenger floor pan seems to be fine though, just a little dented.

THANK YOU! That's exactly the kind of information I needed.

Basically, guys... I know I'm no expert here. However, I have enough of an understanding on exhaust dynamics to make a set-up that will work okay. You need to remember one incredibly simple fact... I am on a very tight budget at the moment. Right now, I am more concerned with the car running well than I am about designing a high-performance exhaust. I simply don't have the kind of money needed to do so. I just want to make sure it will run well, and get decent power. If it sounds good, then great! There are exactly zero kits for the swap, and I'm flying by the seat of my pants a little bit. However, I am not going into this project blind, as some of your posts seem to be hinting at. The shop I'll go through to build the exhaust will be more than happy to take my ideas and help make them work, as they will have a better understanding of it all. And if I have to buy headers, instead of making my own, then that's fine. I will do what I have to do to make it work.

If you'll go back in the thread a little bit, you'll see that I was mistaken about the stock Z32 exhaust tubing size in the first place. It is already 2.25", so I'm not down-sizing any time soon. Do you have any idea where that thread is, for the shifter modifications?

I have the FS5R30A. I can't get anything else either. I'll have to get what I already have to work. The FS5W71C came with the Z31, and I have a Z32, which came with the FS5R30A.

I did, but seriously... I promise you that I am not blowing smoke here (no pun intended). Hot gases tend to move faster through the exhaust. Yes, exhaust will cool off as they move through the piping, but it needs to stay hot for a little while. And I'll stick to going with 2.25", thanks though. Just having mendrel bent tubing, no cats, and free-flowing headers will be a huge help to the engine. It's not that I'm trying to tell you that you're wrong, but I am going with what I know, and the link didn't really go into how to apply the information.

And apparently, I was mistaken on the stock exhaust size for the z32... It's already 2.25. Any smaller than that, and there'll be some performance issues. I'll still be making my own headers, instead of relying on the stock parts.

Cool gases exit the exhaust faster...? Okay... Tell you what, If you can prove to me that cool exhaust is better on a N/A, I'll believe you. Give me some irrefutable proof, please. Bigger isn't always better...

I am pretty sure I do... The stock 2.5 inch tubing size can support a little over 1000 hp, as proven by Z1 Motorsports on their widebody Z32. Now... Do I need that big of exhaust? No. The fact of the matter is this... What do motorcycles have done to their exhaust to improve performance? Low-restriction, high flowing exhaust. Now, that doesn't mean that a larger size is put onto the bike. There are times that a smaller tubing size is preferred. Tubing size actually has a huge effect on how well exhaust gasses flow. Too small, and there isn't enough space. Too large, and the gasses cool off too much to flow well. A higher flow capacity doesn't equate to better flow. Actually, it can be quite the opposite. Yes, if one were to take, say, a V8, and build it for max output, a larger exhaust will most likely be needed. But does that mean that stock exhaust size is the lowest you want to go? With the VG30DE, a smaller size exhaust, with very little restriction, is more than capable of supporting the motor's output. It could actually improve the performance, because the exhaust gasses may be able to flow better. Without any real restrictions, the 2.25" exhaust should, at the very least, flow just as well. The correlation between flow capacity and actual flow only exists when the engine's pumping capacity is taken into account. Theory is great, but it needs to work in the real world, or it's just theory. Lastly, remember that I'm not working with a turbo motor. Yes, larger exhaust after the turbine can help it spool better, but it's the complete opposite when working with natural aspiration.

As far as the exhaust... I will be whipping up a set of 2.25" custom headers using the mating surface off an extra stock set. After that will be 2.25" straight-pipe with twin glass packs. The step down from 2.5" to 2.25" exhaust should actually give the motor a little bit of a performance, since it will keep the exhaust gasses a hotter than the larger size, making it flow faster.

If I can add something to them to make it work, then great, but It's still going to be mounted as close to the firewall as possible.

I want to mount the VG as far back in the engine bay as possible. The motor isn't light, and weighs about 200 lbs more than the L28, so the farther back it is mounted, the less it will affect weight distribution.

Also posting about this build on HybridZ.com

I understand that, I just wanted to let people know what I'm doing on here. Plus, the questions I would need to ask would be ones that people here would be able to answer.

So, It's going to get the Z32 5-speed, 80-83 R200 3.900:1 final drive, and 195/60 r15 tires. Also, I'll fit an Autometer electric speedo and tach, and other gauges. Need to figure out how to compensate for the shifter on the Z32 5-speed being an extra 5.5 inches farther back, and of a different design, as well... The car will have about 235-240 hp, weigh about 3100lbs (200lbs lighter than my 2+2 z32 was), and I chose that tire size/diff gear set because I'm looking to get as close to the Z32's final drive as possible. The tires should give the final drive gear reduction enough of a boost to allow for a little better acceleration than the N/A 300zx, but also be geared high enough to keep the fuel economy close to what the L28E L-Jetronic FI has. The thing won't be a race car, but it won't be horrible either. Plus, I will be able to swap a VG30DETT directly into the car later on. I'm also keeping the L28 mounts in the car, to be able to swap the original motor back into the car.