GRAND-AM 128i Build Thread

[Evice]

It is a cross post, but I thought 128 family would be happy to see what can happen to a 128

http://forums.bimmerforums.com/forum....php?t=1955577

ali.

[TheSt|G]

Certainly wouldn't mind some insights from them as to what they have done to the car enginewise.

[Evice]

Engine is a Dinan package. They are not allowed to do much on it. Improve reliability with a better radiator and oil cooler and rebuild the engine up to the maximum tolerances as rules allow. That's what I have been told by them.

[andrey_gta]

I want those Rotors

Any idea where to get them from, or at least slats that look like that?

Looks like they are using solid Subframe bushes

[Evice]

Originally Posted by andrey_gta

I want those Rotors

Any idea where to get them from, or at least slats that look like that?

Not sure. I know that calipers wise they are allowed to run 330 calipers, and 330 transmission because they are beefier, but not sure if they are actually running them.

[Greenkirby21]

wow this is so cool. thanks for the post

[andrey_gta]

i spy m3 front control arms, at least the lower arm (what we wrongly call the wishbone)

[Drawn05]

Originally Posted by Evice

It is a cross post, but I thought 128 family would be happy to see what can happen to a 128

http://forums.bimmerforums.com/forum....php?t=1955577

ali.

The exhaust certainly looks huge. I would have thought such a bigger pipe diameter would have been counter productive on a 3L N/A.

[Evice]

Originally Posted by Drawn05

The exhaust certainly looks huge. I would have thought such a bigger pipe diameter would have been counter productive on a 3L N/A.

larger, free flowing pipe typically removes the low end torque, and increases high end power, which you'd want on a racecar.

[Jatterbu]

Guys, sorry it took me so long to post over here. I'll try to update this thread with some pictures if I'm allowed to, the account is new so I may need a certain post count. The build has been completed and the car is being loaded and off to Texas today. I was able to grab this pic yesterday of the vinyl being finished and about to be put on the scale pad.

Originally Posted by andrey_gta

I want those Rotors

Any idea where to get them from, or at least slats that look like that?

Looks like they are using solid Subframe bushes

Shoot me over an e-mail and I can give you info on the rotors. We use the same size rotor as on the 330i and it is a 2-piece design. We also use a 2-piece rear direct replacement rotor for the 128i. This is a fantastic setup for aggressive driving, HPDE and club racing, it provides a ton of weight loss and much better cooling.

Originally Posted by andrey_gta

i spy m3 front control arms, at least the lower arm (what we wrongly call the wishbone)

Yes we use the M3 front control arms in the car. There are quite a few swapped over parts from other BMW models that really make the 128i come to life. It's a fantastic little car!

If you guys have any questions at all, feel free to ask or send me an e-mail and I'll respond as quickly as I can.


Joey
joey.atterbury86@gmail.com

[Hops128i]

what a great link! Thanks! definitely going to watch grand am this season.

[Greenkirby21]

Originally Posted by Jatterbu

Guys, sorry it took me so long to post over here. I'll try to update this thread with some pictures if I'm allowed to, the account is new so I may need a certain post count. The build has been completed and the car is being loaded and off to Texas today. I was able to grab this pic yesterday of the vinyl being finished and about to be put on the scale pad.





Shoot me over an e-mail and I can give you info on the rotors. We use the same size rotor as on the 330i and it is a 2-piece design. We also use a 2-piece rear direct replacement rotor for the 128i. This is a fantastic setup for aggressive driving, HPDE and club racing, it provides a ton of weight loss and much better cooling.



Yes we use the M3 front control arms in the car. There are quite a few swapped over parts from other BMW models that really make the 128i come to life. It's a fantastic little car!

If you guys have any questions at all, feel free to ask or send me an e-mail and I'll respond as quickly as I can.


Joey
joey.atterbury86@gmail.com

thanks for the updates. I wish I could go to the austin race : (. Unfortunately I have midterms that week

[ilikebmxbikes]

That is awesome. Glad to see some 128i love.

[andrey_gta]

Originally Posted by Jatterbu

Shoot me over an e-mail and I can give you info on the rotors. We use the same size rotor as on the 330i and it is a 2-piece design. We also use a 2-piece rear direct replacement rotor for the 128i. This is a fantastic setup for aggressive driving, HPDE and club racing, it provides a ton of weight loss and much better cooling.



Yes we use the M3 front control arms in the car. There are quite a few swapped over parts from other BMW models that really make the 128i come to life. It's a fantastic little car!

If you guys have any questions at all, feel free to ask or send me an e-mail and I'll respond as quickly as I can.


Joey
joey.atterbury86@gmail.com

Car looks great Joey!.
Its nice that alot of the modifications ( brakes, exhaust, m3 parts) are what we are all slowly doing to the 128i's here


If you can explain to us how the oil cooler is attached to the car. I've read that the n54 335i oil filter housing can be used and any n54 oil cooler set up.


I'll email you in a few days regarding the rotors.
I did discover that the 130i used 330i rotors with the 128i caliper, so I hope this confirms what i found.

[M3_WC]

Originally Posted by Jatterbu

Guys, sorry it took me so long to post over here. I'll try to update this thread with some pictures if I'm allowed to, the account is new so I may need a certain post count. The build has been completed and the car is being loaded and off to Texas today. I was able to grab this pic yesterday of the vinyl being finished and about to be put on the scale pad.

Car looks great, I will be at COTA this weekend. Can't wait to see the car in action.

[TheSt|G]

Looking good. Post as much as you can here, we would love to see what you are doing.

[Obioban]

Originally Posted by andrey_gta

Car looks great Joey!.
Its nice that alot of the modifications ( brakes, exhaust, m3 parts) are what we are all slowly doing to the 128i's here


If you can explain to us how the oil cooler is attached to the car. I've read that the n54 335i oil filter housing can be used and any n54 oil cooler set up.


I'll email you in a few days regarding the rotors.
I did discover that the 130i used 330i rotors with the 128i caliper, so I hope this confirms what i found.

Food for thought, at least on the older cars (e46) when there's a variety of brake options, coding should be done to optimize the electronic brake for distribution to the hardware. E.g. if you retrofit CSL brakes to the e46, you recode the DSC module accordingly.

Might be beneficial for you guys as well.

And, if you're going off book (non standard BMW setup or aftermarket), best to match the DSC coding to the closest BMW bias.

How to calculate bias here:
http://www.m3forum.net/m3forum/showthread.php?t=412927

example spreadsheet:
http://www.m3forum.net/m3forum/showp...86&postcount=2

[TheSt|G]

Seeing as there is a dealer recode for the BMW Performance(repainted 135i) BBK, I have no doubt that it is the same.

[Evice]

You guys are over thinking it. Also don't forget this car has Bosch Motorsport ECU. Everything is free for all.

330 calipers will not change braking bias as BBKs would.

[Obioban]

Originally Posted by Evice

You guys are over thinking it. Also don't forget this car has Bosch Motorsport ECU. Everything is free for all.

330 calipers will not change braking bias as BBKs would.

What's different about the 330i calipers?

As in...
more clamping force = altered bias
larger pads = altered bias

And, to the contrary, a well engineered BBK either shouldn't change the bias or should change it for the (experimentally tested by the BBK manufacturer) better.

Either way, coding the car to know whats going on (or as close to that as possible) makes the entire system work better.

[Evice]

Originally Posted by Obioban

What's different about the 330i calipers?

As in...
more clamping force = altered bias
larger pads = altered bias

And, to the contrary, a well engineered BBK either shouldn't change the bias or should change it for the (experimentally tested by the BBK manufacturer) better.

Either way, coding the car to know whats going on (or as close to that as possible) makes the entire system work better.

330 is a little beefier, but in equal amounts F and R. Plus you can use master cylinder to change brake bias (can't say if this specific 128i is allowed to have non-stock MC)

[SkinnyVT]

Originally Posted by Obioban

larger pads = altered bias.

Larger pads don't change bias, just wear rate and heat capacity, surface area has no effect on the amount of friction force

Originally Posted by Evice

330 is a little beefier, but in equal amounts F and R. Plus you can use master cylinder to change brake bias (can't say if this specific 128i is allowed to have non-stock MC)

Similarly changing the master will have no effect on bias as the ratio of front/rear piston sizes will still be the same, the master will only effect pedal travel/effort.