The latest project

[Bill in MN]

I've been threatening to build a track car for some time now and was pretty serious about a couple cars over the past few weeks. Budget in place, if the right car came along it was going to wind up in my shop. As is usual with me, I spent lots of time researching and shopping, all the while neglecting to pay attention to the semi-dead S2 sitting 25' from my shop door.

Let's see. ....Potent motor and drivetrain (sans driveshaft)? check. Brakes strong enough to throw a guy into the windshield? check . Suspension capabilities in excess of anything I could throw at it? check. Big ass hole in the floor and a bent tunnel? ooops. Can't win 'em all I guess!

The driveshaft debacle really messed up the floor and tunnel but overall the car's in great shape. The floor and tunnel can be pulled back and as long as a cage goes in the risk of structural issues are few.

I don't have a lot of time to play these days but I've managed to get the interior completely gutted and most of the non essential systems removed. This is going to be a bare bones track car with no frills or comforts whatsoever. There's no real target for completion but given this is my only car project this winter, knowing me it'll get done pretty quick and rest assured, done right.

BTW, the slushbox is staying in place. My hot rod buddy and I have a B&M Hammer ratchet shifter converted for using in this car, essentially turning it into a 4sp. sequential shifting gearbox. Given the 3500rpm converter in the thing and the fact that it never goes off boost during a shift it's worth a shot. I fully expect to be flamed for this move but WTF, it never hurts to try.

I'll keep everyone up to speed as things progress.

[T_C_D]

Awesome! You should consider a large capacity tranny cooler.

[Duke]

If you are really going to do this. Why not use a E30 chassis?

They have proven very successful on the track. The E28, not so much.

[Jeremy]

If you are really going to do this. Why not use a E30 chassis?

Well, the fact that he just happens to have an e28 chassis laying around might have something to do with it.

They have proven very successful on the track. The E28, not so much.

I dunno, I haven't seen any truly prepared e28s AT the track, have you? I'm assuming we're talking 1/4 mile here.

Go for it, Bill. Should be a riot. Be prepared to cut the springs to get the ride height where you want once all the lightening is done.

Jeremy

[Duke]

I dunno, I haven't seen any truly prepared e28s AT the track, have you? I'm assuming we're talking 1/4 mile here.

Nope, taking track, not drag strip. Check any SCCA standings that the E30s are in, big winners. E28, not so much.

[Jeremy]

I dunno, I haven't seen any truly prepared e28s AT the track, have you? I'm assuming we're talking 1/4 mile here.

Nope, taking track, not drag strip. Check any SCCA standings that the E30s are in, big winners. E28, not so much.

Ed Walters was quite successful. You're right that the e30 is a better track car platform, but again, Bill has an e28 sitting there, not an e30. Use what you have.

Jeremy

[Duke]

Ed Walters was quite successful. You're right that the e30 is a better track car platform, but again, Bill has an e28 sitting there, not an e30. Use what you have.

I agree. If Bill is planing on being really competitive though, the E28 will just disappoint. He should not sink a lot of money in the wrong platform.

[T_C_D]

If you are really going to do this. Why not use a E30 chassis?

They have proven very successful on the track. The E28, not so much.

It's a car for Driver's Schools not actual racing.

[Skeen]

...and there are e28s that have been made successful track cars. Coil overs will be necessary eventually.

[FirstFives Dictator]

Hi Bill
Skeen is right on the money. some additional thoughts:

...and there are e28s that have been made successful track cars. Coil overs will be necessary eventually.

Yes and spring rates that will surprise some.

Adjustable trailing arm bushings another nice to have (dial out some rear camber from lowering car)
Or get the slotted tabs and modify your subframe (see Ireland Engineering). You may have to flare fenders once you dial out some neg camber but it will be worth it.

E28 will be a little easier to drive (E30's rotate a little quicker. read: spin out) but if the correct mods are done, car should be a blast to drive.
I'm thinking 400-500 lb's inch front, 250-300 lbs/inch rear. 2.5 - 3 degrees front, 2 degrees rear, some decent aftermarket sway bars and koni SA shocks all the way around. The 8610 race inserts are shorter (and my next shock) and would allow you to shorten your front strut housings when you are converting them to coilover struts. Lowers car and preserves shock travel.

This is me at last weekends autox running old Hoosier R compounds; can you believe how friggin stiff the Hoosier sidewalls are?

[Bill in MN]

This is strictly a DE car and moreover, a toy. I can't fathom not having at least something to tinker with over the winter and hell, it was begging to be converted.

Considering it's a known quantity and is pretty well set up for learning the basics, getting another car would not make sense. There's plenty that can be done in the future to make the car more capable if I 1) like the DE stuff and 2) am any good at it. If that happens and I don't like the e28 on the track I can always find something else. I kinda doubt it though. Flying in the face of convention has always been one of my favorite things to do. Believe me, I've heard the "you don't want to take an e28 to the track" before . Baaaaah!

What, no flames on the AT?? [/quote]

[Boru]

Bill, though you have the E28 already I think you'd be better served and ultimately be more competitive if you acquire the stolen Ferrari documents from Williams, build an autoclave, buy a 5 axis milling center, forge, mandrel benders, hydro-forming equipment, laser cutters, and a few hand tools so you can, in short order, become the dominant force in world wide auto sports.

Get on that... and can I get an autograph when your task is complete? ...say, next June?

[Bill in MN]

Peter

I've still got those NIB Koni adjustables. PN is 86p-2017. These are specifically for an e12.

Let me know if you still desire them. They won't work in the e28 housing.

[russc]

Um, its Mclaren/MB that recieved the stolen documents!

RussC

Bill, though you have the E28 already I think you'd be better served and ultimately be more competitive if you acquire the stolen Ferrari documents from Williams, build an autoclave, buy a 5 axis milling center, forge, mandrel benders, hydro-forming equipment, laser cutters, and a few hand tools so you can, in short order, become the dominant force in world wide auto sports.

Get on that... and can I get an autograph when your task is complete? ...say, next June?

[Boru]

Um, its Mclaren/MB that recieved the stolen documents!

RussC

Bill, though you have the E28 already I think you'd be better served and ultimately be more competitive if you acquire the stolen Ferrari documents from Williams, build an autoclave, buy a 5 axis milling center, forge, mandrel benders, hydro-forming equipment, laser cutters, and a few hand tools so you can, in short order, become the dominant force in world wide auto sports.

Get on that... and can I get an autograph when your task is complete? ...say, next June?

That's exactly what they want you to think... 8)

I actually typed McClaren first, then thought 'or was it Williams'... then I realized I didn't care.

[Matt]

I ran my bone-stock M5 at the track closest to Bill for a few years before buying my E30. One of the _very_ smart techs at Motorwerks BMW in Minneapolis also ran his E28 535i at the track for a couple years.

There was that guy in virginia with the e28 M5 with the B36 engine that was a caged dedicated track car..and he was always posting vids of him ruining people on the track.

Nobody disputes that the E28 has a weight/size penalty, but it's still competant at the track. In my M5 on street tires I got point-bys from all 3 generations of M3, and a z06 (in the rain). The E28 is a perfectly good platform to decide how serious you want to be about this stuff, and to work on being a better driver.

IOW -- E28 vs E30 doesn't matter until the driver isn't the limiting factor.

[Bill in MN]

Matt hit the nail on the head.

By the way, Matt was turning some very impressive lap times at BIR a few weeks ago in his e30. Did I hear you blew a head gasket? Make it home alright?

[T_C_D]

IOW -- E28 vs E30 doesn't matter until the driver isn't the limiting factor.

Does that actually ever happen?

[Jeremy]

IOW -- E28 vs E30 doesn't matter until the driver isn't the limiting factor.

Does that actually ever happen?

On relatively stock cars, yes.

Jeremy

[T_C_D]

IOW -- E28 vs E30 doesn't matter until the driver isn't the limiting factor.

Does that actually ever happen?

On relatively stock cars, yes.

Jeremy

HaHa, wisely stated by someone with how much track experience?

[FirstFives Dictator]

on the SCCA forums someone' s tag had this qoute:

"he ran out of talent before he ran out of nerve"


Wish I knew the story behind it...

[Matt]

IOW -- E28 vs E30 doesn't matter until the driver isn't the limiting factor.

Does that actually ever happen?

In a strict sense of the word -- no. A perfect machine will get more out of a car than an imperfect human.

In a practical sense, yes.

Without getting overly long-winded, once you aren't learning anything from your current vehicle setup, and you've exhausted the training options that are realistically available, changing the car or the cars setup can be a good way to start the next round of iterative improvments. I'd argue that there's a limit to how much you can improve the driver in isolation.. .just like how improving the springs alone limits how much overall improvement happens in the car. The driver, like the springs, are part of a system that iteratively improves with experience and change. The man and machine are always pushing until they've identified the next plateau, at which point a change is needed to push past it.

In my case, for a variety of reasons, changing the platform was probably the right way to break the plateaux. Adding the grip of R-comps and losing all of the S38's power has shown me lots of gaps in my driving that either didn't exist or weren't noticable --- to me or to my instructors -- in the M5.

It's very nice when instructors are saying "nice" all the time or are refusing to ride along with you because you carry more speed than they are comfortable with, but it doesn't necessarily help you get faster.

The next "upgrade" I'll do to my E30 is data logging.. probably a G2Extreme unit. I know that the driver has plenty of room for improvement, but I don't know where to find it. Hopefully the G2 unit will help me understand where I can get faster.. until I've again hit a plateau and need to do something else to the car.


And yes, I left early on sunday because the head gasket was starting to go, according to 3 different guys. White gunk on the end of the dipstick (huh huh huhuh mmmh huhuu) and the coolant level was getting lower as the weekend wore on. I made it home OK and have parked the car since.

[Skeen]

Man, so many things to say. Back to the original topic though, I think you're gonna want spring rates even higher than what Peter quoted unless you are driving it on the street any significant distance. Also, camber is tire-dependent. RA-1s will want as much as you can get (think 4*+). Hoosiers won't need as much. Definitely get adjustable shocks and coilovers with a good range of ride height adjustment. With those few options, you can dial in the car pretty well.

[FirstFives Dictator]

Man, so many things to say. Back to the original topic though, I think you're gonna want spring rates even higher than what Peter quoted unless you are driving it on the street any significant distance. Also, camber is tire-dependent. RA-1s will want as much as you can get (think 4*+). Hoosiers won't need as much. Definitely get adjustable shocks and coilovers with a good range of ride height adjustment. With those few options, you can dial in the car pretty well.

Probably so, but if you get beyond 550 lbs per inch, make sure your shocks are valved for that and have some room to adjust for 150-200 lbs more in case you need/want that.

800 lbs/inch for a car with a lot of grip is probably not out of the question, but I doubt any out of the box SA or DA shock can handle those spring rates.

It think 8610's max out at about 600 lbs

[Matt]

Man, so many things to say.

Don't hold out on us. You're the only pro here that I'm aware of.

[FirstFives Dictator]

Man, so many things to say.

Don't hold out on us. You're the only pro here that I'm aware of.

I'm not sure how much experience Skeen has developing e28 chassis. I think he would have given you hard #'s if he had them.
There's are 3 e12 racers with e28 and rear suspension on our site (firstfives). I think 800lbs per inch front sounds familiar.
Like I mentioned before, you'll need custom valved shocks for those rates. Ireland or Ground Control can give you suggestions. I'd have some rough corner weights available in case they ask.
I believe Lee Cornett's car is running 800 lbs front and the stock Koni SA aren't able to completely dampen them.
I think the rates should be virtually the same from e28 to e12 if the vehicle weights are similar. Don't use e30 numbers, rear springs are in-board and not coilover.

[Tammer in Philly]

Man, so many things to say. Back to the original topic though, I think you're gonna want spring rates even higher than what Peter quoted unless you are driving it on the street any significant distance. Also, camber is tire-dependent. RA-1s will want as much as you can get (think 4*+). Hoosiers won't need as much. Definitely get adjustable shocks and coilovers with a good range of ride height adjustment. With those few options, you can dial in the car pretty well.

Probably so, but if you get beyond 550 lbs per inch, make sure your shocks are valved for that and have some room to adjust for 150-200 lbs more in case you need/want that.

800 lbs/inch for a car with a lot of grip is probably not out of the question, but I doubt any out of the box SA or DA shock can handle those spring rates.

It think 8610's max out at about 600 lbs

Most places that will well you a true track setup will match the valving to the springs you choose, and they will help choose springs based on chassis characteristics (except for most vendors, the E28 is an unknown quantity so do some homework). Since the E28 has a coil-over rear setup already, the wheel rate and the spring rate aren't that far offset; this makes the appropriate spring rate different from, say, an E30 with inboard rear springs.

Everette P. in Virginia is an instructor with a 535i track car. Gutted to the bones, not even the stock dash, it weighs ~2800 lbs with 1/2 tank. He's running a 4.10 diff and a mildly worked M30B35 and he is FAST. The gearing is a little bizarre but it works for him; he spends a lot of time in 5th. So while an E28 will always weigh a couple hundred pounds more than an E30 with similar prep, it's not a bad platform for a track car. And there's the fun of going out and raising hell in a sedan. :-)

-tammer

[FirstFives Dictator]

BTW, I am totally unimpressed with Ground Control shocks

Get Koni SA's and don't look back