BRracing 135i - not your avg dd

[miro2296]

sweet sweet ride! we need some video of it in action!

[brracing]

Thanks for the continued support and questions.
We started out this as just another project....to develop a cheaper M3, that could kill anything...and now have fallen in love w the car...it has such great personality and potential.....WOO HOO.

We will have pics of the engine bay next week....we have another new intake from ASR to install.....and we know the results already, but the new piece is going to be very nice.

Here are add'l pics of the harness bar main hoop base plate...you will notice that the main hoop is out a little from the side frame rail, this was to provide more clearance on the seat belt attachment, and to have the hoop be more centered in the base plate. The base plate mounts are the side seat belt mount (existing BMW mount), and the main bolt that goes thru an existing drain plug hole in the floor pan. We cut the carpet on the rear and side edge, and insert the main hoop, then replace the carpet over it so that it looks nearly original.
The last pic is of the close up of the rear shock tower bar, where we have cut out the carpet to the main bulkhead where the actual mounts are, and you can see the clearance to the rear seat area as well as the attachment and weld quality.

[datbimmerdoe]

Looks sick fawk!!!

[heyimsam]

OMG i am so glad you guys are here please save us from this wild understeer

[heyimsam]

how do the ast ride on the street as well?

[pkcormier]

You also mentioned above you run Advan tires non-staggered. What size? I've used Kumho 245 V710 (now no longer produced) and Toyo R888 255. Square setup. Looking for another 255x35x18 alternative to try for the track.

[brracing]

Don't want to hijack my own thread....
AST's. We have done Bilsteins, Teins, TCKline, GControl, Moton, JRZ, and Penske.
What we find is that the suspension solutions fall into several groupings.
(1) plain upgraded sport shocks and springs...in various package. Can be a good upgrade, but mostly driven by the customer looking for a low price upgrade, and too many tradeoffs, and not a true "matched" kit
(2) coilovers (like KW, Tein, GC, TCK, AST 4xxx, Bilstein PS9 or 10). These offer the first real upgrade in the shock design, offer the height adjustment that so many want or need....but, the shock and spring package are starting to make huge tradeoffs...either slightly too stiff for the street, and too soft for the track or autox.
(3) Upgraded coilovers....can be duals or up. Now the package has been upgraded again, but now allows a greater range of adjustment.
(4) Maniac quad adjustable...only needed for the track, and only for those who really know how to tune a suspension, not just turn some dials.

What we found or were trying to go after was indeed a kit that would completely serve us on the track, but that we could get the range of adjustment that it would work well for the family and for the bumpy freeway.

The AST 5300 give us exactly what we were trying to go for. We can make infinite adjustments with the cannisters, and altering the Nitrogen pressure if we really want a specific solution or capability. But, we can quickly....and I mean quickly, make some simple adjustments and drive the car on the bumpy freeway without a problem.
We can do this w some other high end solutions (our E46 M3 has high end Moton's)...but, for the price, the AST are the best combination of adjustment, performance, quality, and design that we have found.

[jibaholic101]

where are the dyno pulls?!?!?!?!

[brracing]

Tires used -
Yoko's
Toyo R888
But, there is a brand new Hoosier that has just been released (not on sites yet), that will be in a 245 type size, that really is the size of a 255, and this is the best track tire we have found, it's just that you trade off tire life for bite. The Toyo will last longer, but the Hoosier provides more grip.
We have not put full race slicks on, as we're concerned that if we don't do something to the oil system pickup, that the amount of G's we would get (similar to our full race car), that we will get oil starvation, and w all the oil issues already w this N54 turbo motor, don't want to risk it yet.

AST's run great on the street when you adjust the 5300 down to a softer setting (but you don't want to go full soft...which is amazing that you can get that much range of adjustment in this shock)

Dyno pulls...as mentioned, we've got a couple more tweaks to do to the motor, then will go to the dyno. We know our friends at ASR have gotten over 500+ at the WHEELS...but, their implementation is definitely on the aggressive side for our target, a plain daily driver and track maniac...but, if you want to kill everyone at the dragstrip or at that stoplight....talk to Abid at ASR.

[jibaholic101]

Originally Posted by brracing

Dyno pulls...as mentioned, we've got a couple more tweaks to do to the motor, then will go to the dyno. We know our friends at ASR have gotten over 500+ at the WHEELS...but, their implementation is definitely on the aggressive side for our target, a plain daily driver and track maniac...but, if you want to kill everyone at the dragstrip or at that stoplight....talk to Abid at ASR.

when is ASR going to start putting their products up on the internet to buy?

i have been waiting for so long for their shit! i love their products

[larryn]

Originally Posted by heyimsam

OMG i am so glad you guys are here please save us from this wild understeer

I hope you are joking. If not, then I suggest driving schools. Much reported "wild understeer" is a direct result of "wild driving"... I am an instructor and see "wild driving induced understeer" all the time.

Unless you're kidding, of course.

[brracing]

Their not joking about the "wild understeer" inherent in the BMW 135i. While BMW has been designing in understeer in their more sporty cars since the mid 90s, the 135i has a much greater element of it, due to the RunFlat tires, weight distribution, and heavily staggered tire size (fronts are way too small). It doesn't rear its head quickly when just doing daily driving, it feels responsive and fine. But, even on freeway onramps and exits, if pushed you can feel it come on. The car just won't completely rotate.
Get it to the track...and oh my.....you wonder if the car will ever stop pushing. I'm an instructor for several organizations, and a racer of over 16 years, and this car does not rotate, and pushes like a pig. Not on initial turn-in, but from mid turn to exit....you have to use the relief of the throttle to get the front end to bite.
Take it to the tracks, and you wonder if the thing will ever come around. Turns like Turn 2 at Laguna, Turn 2 at Thunderhill, and Turn 6 at Infineon......not good, not good at all. You just give up huge amounts of time, and you can't get on the throttle at all.
But, all is not lost....hence, why so many of us have been working for so long to design out the understeer. And, it can be done, and done without inducing throttle oversteer on turn exit. But, it doesn't come cheap like the solution did for the E46 M3.

[larryn]

"Wild understeer" and "pushes like a pig". Mild exaggeration, or are you comparing it to a Exige S or track car?

I've been tracking BMWs since 1986 (8 time owner), and yeah, there's some push, but come on... a good 50% of that is the 215 runflats up front. Added negative camber is another 30% of the mechanical (non-driver-induced) understeer fix for the non-track-cars here.

If you do want to have more fun doing AX and DEs (and you've taken care of the driver induced understeer component), then it makes total sense to have a car like yours. I'm loving seeing it here, btw.

[brracing]

Don't do Autox...but do full track days.
We currently have 5 BMW's, counting our BMW dedicated race car.
Use the 135i as our current instructor car along w our new 2010 GT3. The car has such great potential, that's why we keep adding to the list of enhancements, as each enhancement seems to have a great return....unlike so many other cars.
And, yes, I would compare the handling to that of the Loti...we want a near neutral balance all the time, and be able to dial in the changes that we need for a course like Laguna where it injects understeer anyway, versus a track like Infineon.
But, heck, we'll run with anything out there......from Vipers, to Vette's, to GT3's, to Loti (ate them up a long time ago before we got anywhere close to the changes we have now)...the only other car that we haven't been able to consume yet is an Atom w upgraded motor and full race slicks. But we want the car as nuetral as possible, so we can get the most from the car all the time.

[Justin(OKC)]

I hope you don't feel too bombarded with questions, but your car has generated a lot of interest!!! I actually want to verify what some others have questioned as well regarding your spring rates. From your posts it seems like you have tried multiple setups. Have you tried different spring rates? I'm curious how you ended up with 650#/650# (f/r). I heard about your car a few months ago and tried to get an idea of what spring rates you were running. Looking at vorshlag's site, I figured that the AST 5300's they have pictured for a 135i was for your car. Their picture states the springs were 550#/850# (f/r). Could you give your impressions of what you have tried and how you ended up with your current spring package? I will say that 650#/650# seems like a strange combination. It looks like a spring setup for a car that has been converted to a true rear coilover. Maybe you have gone with the softer rear spring to compensate for your UUC swaybars.

My AST 5200's are sitting on a FedEx truck here in town as I type this. I just totally took the advice from Harold at HP Autowerks when selecting spring rates. I am going with the smaller M3 swaybars and then am doing 400#/800# springs from Swift. I was concerned that my front springs were not going to be stiff enough, but decided to just try it as they are not that difficult to change (except I didn't factor in the hoses and external canisters...oops). Also, am switching to the M3 rear control arm which changes the mount. Hence, my rear shocks are actually for an M3. I'm excited to see how it turns out and realize I'm likely going to have to play with the springs. After reading your post, I'm kicking myself on the rear hoses. I had no idea that I needed to get longer ones to mount them in the trunk. I may have to drive a few hours to Dallas to visit Vorshlag and change it.

Sorry for the lengthy post, but I want you to know how much I appreciate you posting the info on your car. Any plans for a Quaife or Wavetrac?

[heyimsam]

Not to steal your thread! but No i am not joking I have been racing for sometime now, and I really enjoy the car, but if you try to go ten tenths the car pushes bad. I didn't insult the way you drive please sir don't insult mine! when you turn in and the weight transfers the car pushes hard. I believe it is because of the tires, and a combination of other things as well.

look at the article in road and track I believe where Randy Pobst even says the same exact thing! maybe he doesn't have enough experience either tho.

anyways br great introduction to the forums! and cannot wait to see more!!!

[brracing]

(1) Spring rates. We have run 450/450...way too soft, even for daily street driving. Then tried 550/550...works great for the street, still too soft for street and track use. Then tried 650/650...works great for standard powered 135i's, but if you add a lot of power, the rear will be too soft....then will need to go to 700# rears. Over the years, we have traditionally run a much softer spring rates than others, using the shock adjustment to perform the magic. And, on our race car, we try to get to where we almost don't need sway bars at all....but there we can play w ride heights, change pickup points, move the CG, etc, and have other tools to play with. On the 135i, we are running the UUC set, and they are working great for us. The car is near nuetral now...after all the changes.
(2) We are now at a point where we need to solve the known issue w brakes...and we will likely be trying a new set of StopTech brakes (calipers, rotors, and PFC pads), as the brakes are a known issue. And, we need to solve the problem w the diff...question of an OS-Giken ltd slip or a special diff made by Dan at Diffs Online...who makes most of the top BMW racing diffs (he has regular rebuilt diffs too...a great guy).

[VMRWheels]

Nicely done guys! The car looks great. What tracks have you guys gone to so far?

-Charles@VMRWheels

[m3bs]

Originally Posted by brracing

(2) We are now at a point where we need to solve the known issue w brakes...and we will likely be trying a new set of StopTech brakes

I contacted Stoptech a while back and they said there were no plans to develop a 135i application. Have they changed their tune, or are you going to develop your own setup with their caliper?

[and 1]

Originally Posted by larryn

I hope you are joking. If not, then I suggest driving schools. Much reported "wild understeer" is a direct result of "wild driving"... I am an instructor and see "wild driving induced understeer" all the time.

Unless you're kidding, of course.

hope that wasn't on any of my runs!

[brracing]

To answer the other questions just mentioned...

1) We have been to Thunderhill, Infineon, Laguna Seca or aka Mazda Raceway, and are looking to make a trip down south to Buttonwillow and possibly cal Speedway.
We have found that all of our local tracks provide some of the best testing and suspension tuning. Kind of nice to e in the presence of such historic tracks.

2) Regarding ST brakes, we are working on a application for our car and platform, since we are working closely with them on our other new development car the 2010 GT3. We will keep you posted with more information and what we are able to release.

If anyone has any inquiries or would like assistance with anything relative to your 1 platform please feel free to PM us and we will respond as quickly as we can, we dont jsut sell these products we test them to their extreme and ensure they are the right fit for the enthusiasts.

[BMW86]

Originally Posted by jibaholic101

+ 100000

This is my new favourite 135i!! The hood and wheels look amazing, I've been waiting so long to see this hood in Alpine White!! Your car is badass man and the 19's look unbelievable with that suspension setup. Does it rub at all and have you had to roll your fenders??

Awesome work