New to IT, Questions on Suspension

[europeanspec]

Hello, everyone,
I am building a '97 318is for ITA. Is there a rear camber arm that is IT legal? Is the reinforced Motorsport arm legal, or does it have to be the stock arm? How are you e36 guys getting enough camber out of the rear?

Also, does anyone know of good performance software for the four-banger? I know that hardly anyone runs it, but if you have some good info, I'd be much obliged.

Thanks,
Andrew Smith

[europeanspec]

subscribing.

[TroyM857]

Andy,
Do some searches and I think you'll find alot of the info you're looking for. I found this searching BMW 318i:
http://www.improvedtouring.com/forums/showthread.php?t=18797&highlight=318i

See you at the track Sunday,
Troy

[europeanspec]

I come all the way to a new forum and I get the same jerks answering my stupid questions. What is this, the internet?

That thread finished with the same conclusion I keep hearing: it will not be competitive. Regardless, I'll build it anyway and run it in NASA as well.

It looks like I won't be making it out on Sunday. The wife won't be working, which means I will.:(

[shwah]

Um. Hoping you guys know each other and that is tongue in cheek...

If you must have information RIGHT now. The search will be your best friend.

Let me preface my answers with the fact that I am not a BMW guru by any stretch.
You have to use the stock arm.
You can use eccentric bushings, if that helps in this situation.
The best answer for software on any computer controlled motor is going to be a custom tune, whether via custom burned chip, or stand alone programmable engine management computer.
My experience with the M42 powered E30 318is is that the motors don't leave a ton on the table from BMW. Swapping in a BMP intake netted 5% (~5hp) on a Dynapac dyno - it also improved the torque 'valley' at 3000rpm. Adding a Racing Dynamics chip netted a 12% gain over baseline (w/chip and intake). Adding a Supersprint exhaust to the mix only provided an additional 2%, so 14% gained from stock on a 6 figure mileage stock motor.

So my take is that bolt ons have limited effectiveness, and to build a really competitive one you would likely need to do a full build motor - .040 over, balanced, + .5 compression, blueprinted, custom tuning, custom intake/exhaust lengths.

Hope this helps.

[europeanspec]

Um. Hoping you guys know each other and that is tongue in cheek...

If you must have information RIGHT now. The search will be your best friend.

Let me preface my answers with the fact that I am not a BMW guru by any stretch.
You have to use the stock arm.
You can use eccentric bushings, if that helps in this situation.
The best answer for software on any computer controlled motor is going to be a custom tune, whether via custom burned chip, or stand alone programmable engine management computer.
My experience with the M42 powered E30 318is is that the motors don't leave a ton on the table from BMW. Swapping in a BMP intake netted 5% (~5hp) on a Dynapac dyno - it also improved the torque 'valley' at 3000rpm. Adding a Racing Dynamics chip netted a 12% gain over baseline (w/chip and intake). Adding a Supersprint exhaust to the mix only provided an additional 2%, so 14% gained from stock on a 6 figure mileage stock motor.

So my take is that bolt ons have limited effectiveness, and to build a really competitive one you would likely need to do a full build motor - .040 over, balanced, + .5 compression, blueprinted, custom tuning, custom intake/exhaust lengths.

Hope this helps.

Thanks, it does. I don't see a 14% increase as that bad. It may not gain as much as some of the other platforms, but is seems acceptable. I will probably run different engine management and tweak it to the grenade point. I have plenty of spare motors.

Oh, and I do know Troy, though he may not claim the same in public.

Was that intake the multi-throttle, because that wouldn't be legal?

[shwah]

No it was just replacing the airbox with a filter on a stick.

[TroyM857]

Oh, and I do know Troy, though he may not claim the same in public.


I will publically admit to knowing Andy. He the biggest BMW fanboi I know.:D

[JeffYoung]

Victor Manning races one of these in the SEDiv. Good guy, see if you can contact him through Evan Darling.

Also, a request was made to reprocess this cars weight (and lower it) and it seemed to me (not speaking for the ITAC here, just me) have merit. It will be voted on soon.

[Z3_GoCar]

A new weight won't help if it already can't get to the weight it's at. A new weight would help the Z3 though... But the only way weight will drop is if it's shown that the standard gain is optimistic in this case, and it's been repeatably demonstrated that this can never be shown sufficiently enough. I think the M-44 and the Toyota 4AGE share some of the same basic problems and will forever be a tweener motors, IMHO. I wish that wasn't the case, because in the scheme of things they're both good motors connected some great chassis'. So, if you really want to build an e-36 318i into an ITA car, I say: Go forth, and let it be so! Because you will only be satisfied racing the car you want to race.

[europeanspec]

I will publically admit to knowing Andy. He the biggest BMW fanboi I know.:D
Mama said, "Go with what you know."

I have heard about the issues with getting the car to weight and making power. It was such a clean body that I couldn't pass it up, which may be a bad thing in the long run. We'll see.

I just received my GCR and haven't memorized it yet, but has the SCCA abandoned the VIN rule? If this thing is not competitive in ITA, I have the resources to convert it to a 2.5-3.0L engine for use in ITS-ITE. Is that legal now?

Again, thanks for all of your help. I'm going to try to make the race at Barber in September with my fellow Louisianians.

[ed325its]

Yes, the VIN rule is gone. Since you have a E36 2-door model (not the ti) you may choose to do an engine swap to any other E36 model such as the 2.5l or 2.8l and run in ITS or ITR. Also be sure to change all other required parts to match the new model. Some of those will be improvements like larger brakes and rotors, some may be less advantagous. But when finished the car must be exaclty like the 325is or 328is you claim it to be.

And if you want to stuff something larger like a 3.0l or 3.2l from an E36 M3 or E46 330, then it would run in ITE in most regions.

[europeanspec]

Yes, the VIN rule is gone. Since you have a E36 2-door model (not the ti) you may choose to do an engine swap to any other E36 model such as the 2.5l or 2.8l and run in ITS or ITR. Also be sure to change all other required parts to match the new model. Some of those will be improvements like larger brakes and rotors, some may be less advantagous. But when finished the car must be exaclty like the 325is or 328is you claim it to be.

And if you want to stuff something larger like a 3.0l or 3.2l from an E36 M3 or E46 330, then it would run in ITE in most regions.
Thanks for the info. How much for your ITR car?

[europeanspec]

One more question (I'm sure there will be more); Can I retrofit the car to run on an OBD-1 harness? I have both setups.

[JeffYoung]

my understanding from my discussions with the one ITA 318is driver I know is that the car can make a lower weight.

I'm pretty sure, but not 100% so, that the 318is was never processed while the 1.9 Z.3 was. The 318is's listed weight in the GCR seems off by quite a bit to me compared to what its process weight should be.


A new weight won't help if it already can't get to the weight it's at. A new weight would help the Z3 though... But the only way weight will drop is if it's shown that the standard gain is optimistic in this case, and it's been repeatably demonstrated that this can never be shown sufficiently enough. I think the M-44 and the Toyota 4AGE share some of the same basic problems and will forever be a tweener motors, IMHO. I wish that wasn't the case, because in the scheme of things they're both good motors connected some great chassis'. So, if you really want to build an e-36 318i into an ITA car, I say: Go forth, and let it be so! Because you will only be satisfied racing the car you want to race.

[europeanspec]

my understanding from my discussions with the one ITA 318is driver I know is that the car can make a lower weight.

I'm pretty sure, but not 100% so, that the 318is was never processed while the 1.9 Z.3 was. The 318is's listed weight in the GCR seems off by quite a bit to me compared to what its process weight should be.
Process weight? To what are you referring?

The GCR lists the e36 318is as 2600lbs. Is that with or without driver? Also, it calls for solid rotors, front and rear, though the 1997 fronts were vented. Do I need to retrofit?

Thanks again for all the responses.

[TroyM857]

Process weight? To what are you referring?

The GCR lists the e36 318is as 2600lbs. Is that with or without driver? Also, it calls for solid rotors, front and rear, though the 1997 fronts were vented. Do I need to retrofit?

Thanks again for all the responses.

Andy, I'm still a newbie, but here's my understanding:

Several years back a process was developed to class IT cars using a mathematical formula along with some subjective evaluations to reestablish a car's minimum weight, which is referred to as the "great realignment". This replaced a very subjective way of establishing min. weights that was previously used. Many cars including the most popular models were run through this process, however the ITAC (improved touring advisory committee) does not have the resources to run every IT eligible car through the process. You have to submit a request to the ITAC along with supporting documentation to have a particular model run through the process.

Most of the people on the ITAC frequent this forum, so I'm sure some of them will also respond to correct anything I may have gotten wrong.

[ed325its]

Thanks for the info. How much for your ITR car?


The car ad can be seen here http://www.improvedtouring.com/forums/showthread.php?t=25906 and I am seeking $18,500, car is ready for a podium finish and comes with all spares. After several years (Andy called me seasoned!) of racing I am going to semi-retire and only run a handful of arrive and drive events each year.

In answer to your other questions.

OBD-1 - If I remember correctly the OBD-1 and OBD-2 variants are acutally different engines. The early 318 is 1796cc and the latter is 1895cc. They are also different spec lines on the GCR. If this is correct you would not be allowed to retrofit the 1997 car/motor to a OBD-1 harness. However, with open engine management you may be able to accomplish your goals without a change in wiring harnesses.

Weight - The GCR listed weight is 2600 lbs. That is the minimum weight for the car with driver, gear, and fuel as it comes off the track. I agree with others that appears a bit high and the car should be reviewed for a possible weight reduction.

Brakes - If the vented front rotors are stock for that car you should provide proof to the ITAC and request a GCR correction. However, I do not think vented rotors were stock on the 4 cylinder cars; 318i/is/ti or the 1.9 Z3. (I am not an expert on the 4 cyl cars so YMMV.)

Please feel free to ask any questions on or off line.

[europeanspec]

Thanks again for the info.

[CCARVER]

I can not wait to pass this car at our local track.

[europeanspec]

I can not wait to pass this car at our local track.

We'll see what happens. Don't use this as motivation to "mis-adapt" my new ecu.

[CCARVER]

You do not have the IT spirit yet.
A true IT racer will give you their spare engine so you will make it out on track.
Just so they can pass you and say they did everything they could to help you lose.
As always, I will be track side with 3+ cars running laps all day long.
See you there Andy.
Carver

[ericblois]

welcome to ITA with another bmw, im not sure 2600 is that far off my e30 eta in ITA is only 2550 and i dont have the rev range of the 4cylinder the aerodynamics or the better rear suspension of the e36's. but man its fun picking on the miatas in the corners

[europeanspec]

You do not have the IT spirit yet.
A true IT racer will give you their spare engine so you will make it out on track.
Just so they can pass you and say they did everything they could to help you lose.
As always, I will be track side with 3+ cars running laps all day long.
See you there Andy.
Carver
It seems that there are very few of these things running, so I doubt I will see that situation. Maybe you could stock a few m44s for me.