E36 M3 Sedan GTS3 Build - Build #2

[BMMMW14]

Hi All,
I am just begining my new race car project and am going to make every effort to completely document my progress, as so many of these build threads have given me great ideas.

If anyone remembers, this time last year I built a '95 M3 in to a GTS3 car and crashed it first day out at Road America.(For the record i am still kicking my rear at least once per day). I am going to try and keep it simple and well executed,worry about going faster AFTER it(I) see a few races.

One thing that i have decided since my last build was to forget about being IP legal. I want to focus on GTS3 and just run CM if I get out with BMW Club. As such, my number one goal is to get weight out of the car.

Car is a no accident '97 M3 4 door. 93,000 miles. Nice to start with a solid car!

Main Goals:
- 2400 lbs. before the cage goes in, using lexan rear windows and only a carbon hood. (i have been involved in dozens of e36 builds and i think this should be reasonable).

- Stock engine internals: I want to get weight down low enough to make this a non-issue. I love my torque curve the way it is right now and want to let it alone.

-Other goals are to have simple wiring, while being as modular as possible. Looking forward to lots of quality time with my Weatherpak kit!


Current Mods:
ENGINE:
-DINAN CAI
-DINAN TB
-M50 Manifold
-EURO HFM
-DINAN Stg. 5 SW
- Borla Cat back (For sale soon)

SUSPENSION:
- Bilstein Group N
- Turner Camber Plates
- Turner Sways

BRAKES:
-HT10 pads
-SS lines
-VT Motorsport

MISC:
-UUC shifter
-UUC tranny and motor mounts

Planned:
- SS Headers and 3" Exhaust (identical to the one inmy old build)
- 6 speed and 4.10 (maybe also may run a 3.73 that I have)
- Oil Cooler and LTW pan (have both)
- X Brace, front strut brace
- Solid Bushings
- No Aero Planned
- Carbon Hood
- ETC !



Group Ns




Thought I would throw that i to show off how good the fit of VT's plates is.

I will update as much as I can. I will really get to the gutting next week. Enjoy.

[eficker]

I like the brake duct at the rotor. Did you make those? Very tidy

[AirDoc]

Subscribed

What valving on the Group N's?....what spring rates?...I'm trying to figure out what spring rate to run with my 300/300 valving Group N's.

Best of luck in your build.

[BMMMW14]

I like the brake duct at the rotor. Did you make those? Very tidy

Those are VT Backing plates and just my own hose seyup. Best backing plates I have used yet!


On the Group Ns they are the off the shelf turner valving and springs. I can find the rates later today. I beleive it equated to 800f/900r. Have not run with them yet though. And they are probably just a stop gap to get things going

[vinnymac]

Good luck with the build. My 99 M3 started life as my daily driver and I started building it for IP but now I run more NASA events than BMWCR. I wish I would have started my build with your philosophy and built specifically for GTS3.

I think sticking with a stock motor and pulling weight out is probably going to yield the most reliable car in the long run.

Best of luck.

[Sammyzuko]

Subscibed! Not everyday you see a M3 sedan built for the track. Looking forward to seeing how this progresses.

[BMMMW14]

Good luck with the build. My 99 M3 started life as my daily driver and I started building it for IP but now I run more NASA events than BMWCR. I wish I would have started my build with your philosophy and built specifically for GTS3.

I think sticking with a stock motor and pulling weight out is probably going to yield the most reliable car in the long run.

Best of luck.

Thanks.

Yeah, I am really hoping that not having to stick to IP rules will be an advantage. My main though is there is plenty of IP stuff I don't have money to do, and there is plenty that costs very little that you can't do for IP. So it makes sense for me.

I think with just bolt ons and a nice exhaust setup I should be able to see 240+ at the wheels. I just could not sleep at night knowing that I have a $10k motor in my car that could pop at any second!

Within the next week I will have it all stripped, progress might be a little slow after that, but no reason to rush it. I am hoping to take it to the track once more in October.. without a cage just to get a baseline for where improvements can be made.

Meeting with my cage builder soon to talk about design. I am going to keep it simple. strong and light...i think.

[vinnymac]

Thanks.

Yeah, I am really hoping that not having to stick to IP rules will be an advantage. My main though is there is plenty of IP stuff I don't have money to do, and there is plenty that costs very little that you can't do for IP. So it makes sense for me.

I think with just bolt ons and a nice exhaust setup I should be able to see 240+ at the wheels. I just could not sleep at night knowing that I have a $10k motor in my car that could pop at any second!

Within the next week I will have it all stripped, progress might be a little slow after that, but no reason to rush it. I am hoping to take it to the track once more in October.. without a cage just to get a baseline for where improvements can be made.

Meeting with my cage builder soon to talk about design. I am going to keep it simple. strong and light...i think.

I noticed you are in Chicago. You should strongly consider Izzy's Custom Cages in St. Louis. Scott (the owner) built the cage for my IP/GTS3 car and I've been very pleased with the results. You'd be shocked at how affordable he is and the quailty of work you get for the dollar. I highly recommend him to everyone.

Here's a link to my cage:
http://www.izzyscustomcages.com/BMWM3Cage.html

[jmitro]

absolutely you can be 2400 lbs (or even lighter) before cage. my E36 sedan is 2425 with cage and about 1/4 tank of fuel.

see my build thread if you need any ideas for weight loss. all my body panels are steel except the hood and trunk. doors are stripped to nothing but skins.

also, why are you using a 6 speed? it's a little heavier than the 5 speed. with a 4.10 diff you will probably need it on high speed tracks.

[BMMMW14]

absolutely you can be 2400 lbs (or even lighter) before cage. my E36 sedan is 2425 with cage and about 1/4 tank of fuel.

see my build thread if you need any ideas for weight loss. all my body panels are steel except the hood and trunk. doors are stripped to nothing but skins.

also, why are you using a 6 speed? it's a little heavier than the 5 speed. with a 4.10 diff you will probably need it on high speed tracks.

I have been studying your build for weeks! Glad to hear that you are down to that weight, makes me feel better.

Only reason for 6 speed would be to get a 4.10+ rear end in there. A lot of this car's time will be at Road America and with a 5-speed even a 3.64 would run out of RPMs. I have considered swapping out my 3.23 for a 3.91 depending on the track, but I would preffer to go with one diff only.

[jmitro]

agreed, i use a 6 speed with a 3.91lsd and S52. 4.10 diff would be a nice ratio

i've done a lot more to the car but haven't updated in a while, I'll try to get some more photos up soon.

[Gunnie]

Sorry to be confused here but wouldn't a 4.10+ run out of RPMs well before a 3.91? I thought the higher the ratio the better acceleration and lower top speed (vice versa).

[warptkid]

Thanks.

Yeah, I am really hoping that not having to stick to IP rules will be an advantage. My main though is there is plenty of IP stuff I don't have money to do, and there is plenty that costs very little that you can't do for IP. So it makes sense for me.

I think with just bolt ons and a nice exhaust setup I should be able to see 240+ at the wheels. I just could not sleep at night knowing that I have a $10k motor in my car that could pop at any second!

Within the next week I will have it all stripped, progress might be a little slow after that, but no reason to rush it. I am hoping to take it to the track once more in October.. without a cage just to get a baseline for where improvements can be made.

Meeting with my cage builder soon to talk about design. I am going to keep it simple. strong and light...i think.

Glad to hear you're gettin' back in the game.. can't wait to see the pics as the car develop! Good luck on things, I, should be starting on a very similar project soon as well... not going as light as you, but same philosophy.

FLMS doing your cage???

[///Mracer]

I also like your approach about GTS only build. should be a fun project!

[jmitro]

wouldn't a 4.10+ run out of RPMs well before a 3.91?

yes. what are you confused about? a 6 speed tranny gives an extra gear so he doesn't run out of top speed in 5th gear

[Gunnie]

yes. what are you confused about? a 6 speed tranny gives an extra gear so he doesn't run out of top speed in 5th gear

I understand he has a 6spd but putting a 4.10 in there would make 6th shorter. That could be good for technical tracks but he would run out of RPMs on the longer straights.

I am just going by him saying a 4.10 would be better since he would have more RPMs which isn't correct since it would limit his top speed no matter how many gears he has.

I would love to put in the figures on my spreadsheet but I don't have the gears or tire sizes so I can't. That would ease my confusion. :p

[BMMMW14]

I understand he has a 6spd but putting a 4.10 in there would make 6th shorter. That could be good for technical tracks but he would run out of RPMs on the longer straights.

I am just going by him saying a 4.10 would be better since he would have more RPMs which isn't correct since it would limit his top speed no matter how many gears he has.

I would love to put in the figures on my spreadsheet but I don't have the gears or tire sizes so I can't. That would ease my confusion. :p

Quickly...
3.73, 5spd, 245/40 17 , 7000 RPM = top speed 138 MPH
4.1, 6spd, 245/40 17 , 7000 RPM = top speed153 MPH

ratios 1-5 on these boxes are the same, 6 is an overdrive.

Does that clear things up a bit?

[BMMMW14]

Glad to hear you're gettin' back in the game.. can't wait to see the pics as the car develop! Good luck on things, I, should be starting on a very similar project soon as well... not going as light as you, but same philosophy.

FLMS doing your cage???

Thanks, good to be back in the game...or getting there!

Unfortunatley, I don;t think funds are going to allow for an FLMS cage, which I will say are just the best.

[Gunnie]

Quickly...
3.73, 5spd, 245/40 17 , 7000 RPM = top speed 138 MPH
4.1, 6spd, 245/40 17 , 7000 RPM = top speed153 MPH

ratios 1-5 on these boxes are the same, 6 is an overdrive.

Does that clear things up a bit?

Honestly, I don't know. I am so tired right now I can't think straight.

Why not just leave the 3.73 in there with the 6spd and get a higher top speed? :

[BMMMW14]

Honestly, I don't know. I am so tired right now I can't think straight.

Why not just leave the 3.73 in there with the 6spd and get a higher top speed? :

I have no need for more top speed.

4.10 allows for greater torque mulitplication, and the gear spacing should be better, we'll see. Road America is about as fast as any road course in this country and I will not be over 153 there! Also, I can stretch it to 7200 RPM which gives me another 5mph.

Ideally I would be at redline, in top gear, at the fastest part of any given track, anything above that does nothing for me.

[Gunnie]

I have no need for more top speed.

4.10 allows for greater torque mulitplication, and the gear spacing should be better, we'll see. Road America is about as fast as any road course in this country and I will not be over 153 there! Also, I can stretch it to 7200 RPM which gives me another 5mph.

Ideally I would be at redline, in top gear, at the fastest part of any given track, anything above that does nothing for me.

Okay that makes sense. I figured you would be running RA since you were in Chicago.

Too bad I won't be building my racecar for another year hopefully in AZ.

[m4f1a]

I have no need for more top speed.

4.10 allows for greater torque mulitplication, and the gear spacing should be better, we'll see. Road America is about as fast as any road course in this country and I will not be over 153 there! Also, I can stretch it to 7200 RPM which gives me another 5mph.

Ideally I would be at redline, in top gear, at the fastest part of any given track, anything above that does nothing for me.

you may want to consider shift points for the track as well. take road america, for example, i'd rather not run out of gear between 5 and 6 or going into the kink.

[BMMMW14]

Yeah, good point, turn 5 at RA is never in the right gear for me. With the stock 3.23 3rd gear would get me all the way to 6 and be just shy of shifting, but it comes out of 5 like a dog, hard to win that battle. 4th always got me nicely through the kink, well last time through the kink was anything but nice!

Going in to 7 at RA is the hardest for me, at near stock weight I just ran out of revs in 3rd at trackout. I would think with 500 lbs less car i can make it in to 4th before then. But I am not going to know 'till I go test it.

[saem3]

Yeah, good point, turn 5 at RA is never in the right gear for me. With the stock 3.23 3rd gear would get me all the way to 6 and be just shy of shifting, but it comes out of 5 like a dog, hard to win that battle. 4th always got me nicely through the kink, well last time through the kink was anything but nice!

Going in to 7 at RA is the hardest for me, at near stock weight I just ran out of revs in 3rd at trackout. I would think with 500 lbs less car i can make it in to 4th before then. But I am not going to know 'till I go test it.

For me it seems that 4th gear has worked better with both of my cars at T7, it's feels like it's too high a gear, but you do go faster than zinging it in third. BTW I do use 6th with my 4:10 at Road America.

Steve E.

[BL Dozier]

building smiles on car at a time. classic. keep it up. sounds like a soild donar to begin with you must realy be into rr