99 Z3 Coupe track /Street car

[BimmerBreaker]

Yeah CMM3's car is great. The M Rain seats are of course the best part...

[CMM3]

Yeah CMM3's car is great. The M Rain seats are of course the best part...

Thanks BB, It's great to see another Coupe evolving into a track car. Like the OP I had a e36 M3 that I used to race and then fell in love with the Z3 and thought what a cool track car it would make.

They are a challenge to get to hook up for sure with the short WB and e30 rear, but that's what makes it all the more interesting and fun.

I just got a complement the other day on the M Rain and told the person to look you up on the forums.

[Remotion]

Everyone trying to down play non-M tyre sizes are essentially racists and I want them banned from the forum for time out.

[jrkoupe]

what ....non m tire size?????

[aussiebj]

Ok so I fixed the rear sub frame, I know my way is not the RF way but mines a track car I'm not going to put the interior back in anytime soon.
First I cut off the lower support , Slotted the inner channel after opening up enough area to fix what I think should be enough area.
Made a 1/4 inch plate for the support slid in place, after plating in the inner channel and welding the plates in , then I put a 1/4 slot in some roll bar , tie it to the shock towers and welded it all up closed in around the roll bar and painted it up

[aussiebj]

Here is how I tied it all in,

[aussiebj]

Then I installed the front false aluminium floors and covered in antislip tape and painted the area black to look stock when you look in .. I had to put the stock seats in as my roll cage did not show up yet , Palmer 9-14 was approaching fast.

[aussiebj]

She was ready for Palmer Motorsports park in mass.
I did remove the rear sway bar , I'm not convinced it works better I did notice more understeer but this could be Palmer ill leave it off as I'm going back to NJMP on 10-9 so I can compare the same tracks with and without rear sway bar
Track vid of Palmer
https://www.youtube.com/watch?v=XAWxz0WQLh4&t=57s

[Bobkid]

I tried mine for a weekend without the rear bar and didn't like the feel as much as just keeping the stock bar in place. It may just be I'm used to how it reacts with the bar, but I'm getting too old to learn new tricks.

Definitely change the ratio in your rear diff. I went with 3.73, and with my S54 it's a good match for my tracks down here. 3.46 might be a better option for your setup, the difference you'll see coming out of the slow corners is amazing.

[aussiebj]

Thanks good suggestion

[PbFut]

Removing rear bar adds more rear grip. So if the car is not over rotating or was balanced before removal, disconnecting the bar will give a feeling of piggish push. Figure out how to get the front to grip more and then you are plus on all 4 corners likely improving overall speed. This is perfect example of changing only one thing at a time. You did and net was not to your liking. So either do another change or return. You are on the right path overall.

[aussiebj]

I think you are right if I had more power I could throttle out of the push but the rear tires are to wide for my little 190 hp..

[aussiebj]

Back half cage made to my specs ordered I need to put my racing seats and harnesses in here ....
check out the first couple of minuets of this video of my friend in a E36 M3 following the coupe at Palmer...
From 2.24 to 4.32

https://www.youtube.com/watch?v=A56cZbUaU30

[aussiebj]

Rear roll bar weld in kit I ordered came in started installing yesterday, NJMP on Monday lots of work to do..

[328 Power 04]

Nice! Would you like a tune for the little 190hp engine? Removes the need for cats, catalyst overheating protection (read: reduced power), and a few custom tweaks.

[aussiebj]

Absolutley

[aussiebj]

Well I finished the rear part of my cage in time for NJMP but did not get time to install the race seats and harnesses so I ran with the stock seats again .. while they are good for street driving they suck on the track..

[aussiebj]

NJMP Lighting day
The car ran great all day way wet up until 1 pm then dried out and I laid my best time there of 1:24 flat .. Not a blinding fast time but this is a 190hp car basically stock, with BC coil overs.....considering Porsche GT3 cars are doing 1:10 flat .. I'm 14 seconds from a car that is as much as my house and almost triple the HP I don't think the Shoe is doing to bad...

Heres a quick video of driving in the rain at NJMP
https://www.youtube.com/watch?v=JYDOAieLdB8

[328 Power 04]

Send me a PM and I can help you out. You would just need a windows laptop with one of those OBD diagnostics cables (INPA K+DCAN or VAG KKL) I always tell people to get.

[Gofast]

for upper end fast track driving, yes , remove rear bar.

FWIW... I like having the rear bar for off throttle rotation... necessary in tighter turns, and great when trail breaking. :-)

Just to add my own experience into the mix...
I also like some rear swaybar, in conjunction with a fat front swaybar.

With no rear sway at all, I found the car picks up the inside front in turns; I need a little bit to keep the car planted and to allow me to work the tail like trkshoe said.
For most tracks I run a fat Hotchkis front swaybar with either the stock rear sway or the even thinner rear sway off a Z3 1.8.

[aussiebj]

I'm putting the Coupe up F/S or trade I want a dedicated track car and cant bring myself to go all the way with the coupe... looking for an 95 or lower E36..
https://www.bimmerforums.com/forum/s...e-F-S-or-trade

[aussiebj]

Here are some pics of the underneath detailing

[CMM3]

What are you using for the rear axle/disk brake assembly. The hats on the disk appear to stick out about 6" from the disk surface whereas mine are much closer in at an few inches?

Have you considered adding adjustment to your rear camber & toe. I. E. Makes a posi-lock kit for the e30 that can be made to work fine with some minor mods.

[jrkoupe]

dont forget its not an M...............can that be the difference u r seeing?.....

the rear offsets I know are different on the wheels

[Remotion]

Yes non-M:s have very long hats in the rear brakes, that makes changing them very hard thing. A thing I am going through at the moment.
I am very interested to hear if those rear brakes have been changed in anyway.