Mild Performance mods for track days with E39 - The Unofficial BMW M5 Messageboard (m5board.com)

kmfullM5 · 10th August 2006, 07:35

Hey gang, I'm a new member that recently bought a 2001 E39 M5. I love the car and think it is the best compromise between usability and performance. I plan on doing a couple of track weekends a year and wanted to get some feedback as to what kind of mods you might suggest. I was thinking about concentrating on some sway bars, adjustable shocks, and upgraded brakes. Also, I was looking at a short shift kit. Anybody that tracks their M5, have you seen any weeknesses with the car or is there anything I should be concerned about mechanically?

I appreciate your help. I live in the Cincinnati OH area if anyone is local.

Thanks again.
Kent

ard · 10th August 2006, 07:45

Pretty good list. The concensus seems to be that not much improvement is gained by changing the front bar.

275 tires on all 4 corners, a Ground Control system, 430lb./in front, 340 or 380 rear, a dinan rear sway bar would tranform the handling. Add a front BBK, or all 4 if you can swing it and you'd be set.

Welcome!

Adam

PS Not sure what that "compromise" thing is you're referring to....

mottati · 10th August 2006, 09:22

Adam's description above would likely make a really nice handling M5 for the occasional track day. Not sure exactly how much compromise you'd get day to day with the springs. Bigger front tires, open the brake ducts and get some high temp fluid first, that will be cheap and have no downside (other than mild tramlining over uneven pavement with the bigger fronts). A rear sway bar is cheap and will help dial out more understeer. Go from there. This assumes you already have some track experience.

I have the dinan stage 3 set up and am pleased with it's compromise, certainly not a track oriented suspension, but considering this is my daily driver 355 days a year, and a track car maybe ten days a year (if i'm lucky) it works for me.
Mike

M5Kid · 10th August 2006, 21:00

Mike,

I've hear so many things about Dinan's Stg. 3 from different owners and the level of it's compliance comapred to stock suspension. Is it actually noticably firmer? I was in S.F. recently on vacation and noticed some pretty rough freeways and roads in the city. How does it fair on these?

If the owner could swing it, do you think they would be better off just upgrading to Dinan Stg. 3 off the bat?

Travis

mottati · 10th August 2006, 21:19

Hi Travis, it is definately firmer, but it really depends on the shock adjustment, and which shocks are being run. I hear people with JRZ's say its significantly firmer, but the jrzs have more range of adjustment, so i've read, so it should be possible to make a jrz equipt car ride better than a koni car. I have koni's, and played around with the front setting a bit initialy, but generally leave it in the same setting. I personally wouldn't want any firmer or lower for my day to day drive.
Mike

Quote:

Originally Posted by M5Kid

Mike,

I've hear so many things about Dinan's Stg. 3 from different owners and the level of it's compliance comapred to stock suspension. Is it actually noticably firmer? I was in S.F. recently on vacation and noticed some pretty rough freeways and roads in the city. How does it fair on these?

If the owner could swing it, do you think they would be better off just upgrading to Dinan Stg. 3 off the bat?

Travis

kmfullM5 · 14th August 2006, 23:26

Hey, Thanks for the info. The rear bar sounds like a good idea. I was also going to include the brake fluid and pad swap. I have had good experience with Hawk HP+ pads in the past at the track. Is there another pad anyone might suggest? Also, I've used Koni yellows in the past and was pleased with their improvement in performance while still being adjustable to a relatively comfortable ride. I'm not familiar with the JRZs. How do these compare?

I have had some track experience in the past, just not with this car. I am going from a front drive, turbo charged car to rear wheel, normally aspirated. I think it's going to feel like I'm starting from scratch.

The compromise I was referring to had nothing to do with the performance of the BMW. We just had our first child and I wanted something that could hold a kid seat in the back if necessary. I was looking for the best "do-it-all" car.

Thanks again for the help.

drabe · 15th August 2006, 05:30

I track my M5. I have the GC kit with 550 front and 425 rear, Dinan bars and the Stop Tech BBK. I run 275 all around. The main weakness is the weight. The GC setup help mitigate some of the understeer. The Stop Techs are superb. I would change the fluids frequently even if the schedule doesn't call for it. Driving style may be important---the car has a lot of torque so be sure you accelerate after the apex otherwise you may be in for some suprises.