Hey I was wondering if anyone on here has ever made a performance car out of the L6, or 635CSI. I am buying a Bavarian Auto ECU chip and not sure what else to do. Any advice is greatly appreciate. Thanks alot.

what a lot of people do is upgrade suspension and brakes. If you like your stock ride height, adding a set of bilstein HD's a good way to make it handle a lot better. You can also add HD upper control arm bushings. The brake upgrade you can do is adding the rotors and calipers from an E34 540. Those brakes are a direct bolt on, but you will need the same size wheels or larger than what the E34 is equipped with. I think they are 15s? Adding an limited slip differential is one of the cheapest ways to go faster.

Your in Wilmington, DE i see, you should come up for the meet im having on June 23rd in Malvern, PA! I live around West Chester PA off of 202, so you arent that far at all. If you wanna join in, send me a PM!

-Jeff

It wasn't already? :stickoutt

The M30 is pretty limited when it comes to naturally-aspirated power gains. The most whp I have ever seen from a M30/M90 engine with a ton of work done to it is about 280rwhp. To put it in perspective, that was after about 25k worth of work.

In comparison, you can hit 280rwhp with a TCD stage 1 kit, which runs about 4k.

Of course, in both situations, a manual is a must, as the stock auto cannot handle it.

Of course, in both situations, a manual is a must, as the stock auto cannot handle it.


The E23 745i guys say the stock autos (if in good working order, of course) are good for about 400 hp (crank) before they give out.

HAving said that, I'd feel much better converting to manual if I were to do a turbo conversion. the manuals can handle a bit more horsepower than that, from what I've seen and been told.

well, im on a limited budget and a ECU chip adds about 20 hp (201 hp) and brings the orque up to about 250. That being said do you think that the automatic transmission can control that amount.

Im sure the auto box will be fine with a chip. Lots of people do it. I wouldnt worry about blowing it. Like xatlas said, if your going to spend 25k on the motor, then you might wanna swap in a stick, but youll be good. Post some pics up of the ride sometime!

-Jeff

here is a link to some pics, when i was thinking of selling her. lol

http://forums.bimmerforums.com/forum/showthread.php?t=712864

Jr,

When you add that chip, please post your experience with it. I have had mine for years now and done ZERO to mod it. I want to add larger rims someday, and an offset set of tires, but, I dont feel like adding mods to it. To me the car performs fine, but, then again I drive like a granny and baby my ride with the hope I can pass it down to one of my sons.
I do plan on putting some extr Umph in my seven, that is my daily driver and I dont plan on keeping that one forever.

Let us know how the perf-upgrade works!

You better keep that car...its too clean to sell! Looks great!

-Jeff

the autos are not that bad, just look at what is being done with the 745s and Alpina also used a lot of autos with the turbo motors. My Alpina has over 220k miles and still has the original auto. It has been serviced but never rebuilt. Look at how many 260 5spd that failed with the 633, or the issues with the early CR 5spd. Just choose your tranny carefully and treat it properly.

Check out Metric Mechanic: http://www.metricmechanic.com/catalog/Anatomy-of-2200-3200-3500.php

Rebuilt M30 3700 HiFlo ST Sport - 270 HP at $6,300 ... and that's just the entry level motor! A rebuild is usually around $4,500/5,000 any way, seems like a great deal.

Defining the Metric Mechanic Engine Models * 2200, 2500, 3200, 3500, 3800 & 4000 - Equals the approximate engine size in cc.
* HiFlo - A head ported for approximately 18% airflow increase.
* ST - Surface Turbulance™ which results in fuel efficiency and emissions.
* Sport - If Sport is listed in the name, the engine has a Sport Cam. If Sport isn't listed, then the engine has the stock cam.

The MM guys do quality diff and transmission work, but I have heard a few bad things about their engines, and I really don't like how they show no dyno proof.

As for the 745, as I understand it, those transmissons have different valve body packages and different torque converters compared to the normal autos.

As for the 745, as I understand it, those transmissons have different valve body packages and different torque converters compared to the normal autos.

There were a dozen or more different valve bodies and t/c used by various models. It was my understanding that they were different depending on the calibration needed for shift points due to differences in rear end ratios and power bands of the engine but the parts were basically the same for the strength of materials.

But even if the "stock auto" can handle it; can you say that "any" BMW 5 spd can? I would think that you would have to be selective of the 5 spd and clutch package that was used in the conversion.

One way to help the 4hp22 box last longer is to source the pistons in the valve body from a Ranger Rover box. It will firm up the shifts and keep the clutchs from slipping.

Vance

There were a dozen or more different valve bodies and t/c used by various models. It was my understanding that they were different depending on the calibration needed for shift points due to differences in rear end ratios and power bands of the engine but the parts were basically the same for the strength of materials.

But even if the "stock auto" can handle it; can you say that "any" BMW 5 spd can? I would think that you would have to be selective of the 5 spd and clutch package that was used in the conversion.

BMW only used four five speeds in the E24, the 260, the 265 OD box, the 280, and the 265 CR box.

The 260 is supposedly a bit weaker than the 265 OD and CR boxes, but many people with TCD kits run just fine with them. The 265 CR box is weaker than the 265 OD box, too, based on how often people have to rebuild them. The 280 is something of an unknown, but I have heard of it needing rebuilds about as often as the 265 CR box.

The main reason why these boxes need rebuilds is the second gear synchro, it almost always goes bad. Other than that, they seem to be fine.

I figured on a better clutch from the get-go, as if you are going to put on a FI kit of some kind, you are going to want to "over-clutch" it by using a clutch rated for way more than kit power, especially since boost is addictive. :)

I think the main thing to upgrade when building an auto is the torque converter, as even Todd of TCD has built an auto, but he upgraded that component. The auto itself can take the power, but the stock converter can't. Somebody like Level 10 should be able to whip one up. The majority of the valve body work is, like you said, to control the shift points, not to make the thing stronger.

You are right about the 2nd gear syncros. the 260 was redesigned and the later ones (with the cooling fins on the case bottom) were better than the first series. But there are still issues with some performance clutch components working within the intregral bell housing on these.

Also because of the hight cost of parts for the 280 trannys you hear quite a few people switching to the 265 OD tranny. The CR sport box has been labled as problematic but I think the biggest issue with it is that the parts are scarce and expensive. I think misuse has attributed to some of the failures.

So for a conversion, the 265 OD has proven to be the best choice for reliability and afforadability. They were found on quite a few models over the years and are very versitile because of the ability to accept a mechanical speedo drive. They were the std 5spd in the pre 82 cars and BMW switched back to them for one model year during the redesign of the 260 unit. They were used again for the e30 M3. And these will accept the m5/m6 pressure plate without any issues.

god i love this forum i learn so much! sorry just had to post after reading all that guys. thanks

and yeah let me know how that chip works out, im thinking about buying one and tossing it in to go with the cam i put in this winter....maybe some injectors too....hmm....anyhow...let us all know what your expierience with the chip is!!

alright i will. im not expecting that i will have any negative feed back to offer you guys. thanks for all the information as well!

Any reason you went with a BavAuto chip versus some of the other, more powerful chips, like Conforti or EAT?

Thought I would post pics of my L6 (complete with recent tranny swap)


http://img.photobucket.com/albums/v389/bicyclefreak/635Csi/CIMG0670.jpg

http://img.photobucket.com/albums/v389/bicyclefreak/635Csi/CIMG0671.jpg

http://img.photobucket.com/albums/v389/bicyclefreak/635Csi/CIMG0672.jpg

http://img.photobucket.com/albums/v389/bicyclefreak/635Csi/CIMG0673.jpg

http://img.photobucket.com/albums/v389/bicyclefreak/635Csi/CIMG0674.jpg

http://img.photobucket.com/albums/v389/bicyclefreak/635Csi/CIMG0675.jpg

http://img.photobucket.com/albums/v389/bicyclefreak/635Csi/CIMG0676.jpg

http://img.photobucket.com/albums/v389/bicyclefreak/635Csi/CIMG0677.jpg

http://img.photobucket.com/albums/v389/bicyclefreak/635Csi/CIMG0678.jpg

http://img.photobucket.com/albums/v389/bicyclefreak/635Csi/CIMG0679.jpg

http://img.photobucket.com/albums/v389/bicyclefreak/635Csi/CIMG0680.jpg

http://img.photobucket.com/albums/v389/bicyclefreak/635Csi/CIMG0681.jpg

http://img.photobucket.com/albums/v389/bicyclefreak/635Csi/CIMG0682.jpg

And my 88 635Csi

http://img.photobucket.com/albums/v389/bicyclefreak/635Csi/CIMG0649.jpg

http://img.photobucket.com/albums/v389/bicyclefreak/635Csi/CIMG0635.jpg

actually i did not order it yet, but do u have any other ideas other thanb BavAuto i should look into?

and jus curious how much did that trans swap cost?

and jus curious how much did that trans swap cost?

You can find donor trannys for less than 500 bucks, and then figure labor.
DIY with some buddies is the way to go (if you have the knowledge) or figure labor at 500-700 bucks.

You can find donor trannys for less than 500 bucks, and then figure labor.
DIY with some buddies is the way to go (if you have the knowledge) or figure labor at 500-700 bucks.

And then add in for the clutch set, the tranny mounts, shifter rebuild parts or short shift kit, resurface and balance flywheel and misc nuts and bolts. Then you have to figure on a pedal assembly if you did not get that with the tranny (the e28 is different) and a different driveshaft (is it good? or need rebuilding). Did you get the clutch hydraulics with the tranny and even if it is included do you want to reuse them. If not then you will need a clutch master and slave cylinder. It is not difficult to source the parts but don't think you can just get a tranny and a few buddies and get the job done in an afternoon.

Check this link for some detailed info on prices and parts needed. He did not go with a new clutch and did not have labor cost and the price was still $1200.

http://www.oo00oo.com/tranny/

Here is another link with info on the swap.

http://www.e28planet.com/DaveKanTransGuide/index.html