rear subframe and camber adjustment

[IRideFixed]

after searching, alot...

i could not find how much is safe to slot the inside holes for camber.

also, if changing the camber, will the toe be effected? if so, then i guess slotting both holes would be best but im really only interested in camber at this time.

[BoomerDJ]

cheack the FAQ, everything is there

http://forums.bimmerforums.com/forum...7#post15877487

http://forums.bimmerforums.com/forum...d.php?t=948986

[IRideFixed]

neither thread states how much you can slot on your own using a dremel or the like. i dont think ill be purchasing a kit if its not necessary for minimal adjustment.

[Layne]

It can't be adjustable without the kit, there's no way it will stay in place. (some people swear it will never stay in place even with the kit, so they weld it) First calculate how much you need to move the hole to get the camber setting you want. If the proposed new hole completely clears the old one and it isn't too close to the edge, just drill it and you're done. If it overlaps the old hole, or is too close to the edge, you'll have to weld some new steel on there and then drill a hole in that.

[IRideFixed]

i was hoping there was a magic safety number... guess ill see what i can do when i get around to it and post what i end up with.

if slotting, i was just going to weld some nasty strong washers in place.

[jrcook320]

I disagree with you, Layne. My subframe IS slotted, without the kit, and it IS staying put with autox and track use. Is it ideal? no. Is the kit better? yes. Is it best to weld washers in place once you get your alignment set? yes.

I originally slotted for both camber and toe adjustment, 1/2" for camber, 1/4" forward for toe. 1/2" for camber was not enough and I recently went back in for another 1/8", next time I'll probably go in for another 1/8" for 3/4" total camber slot. Remember when you do this that you have to slot the inside 3 of the 4 mounting plates for camber adjustment, not just both plates that make up the inside mount, or you'll put the trailing arm in a bind. In other words, you should be able to push a straight dowel through all 4 mounting holes without it having to bend for an unslotted inside plate on the outside mount (if that makes any sense???)

As for toe adjustment, I was dumb and only went forward for more toe-in. But, when you lower an e21, you get more toe-in so really I went the wrong way. You want to slot that side toward the back if you do any toe slotting, but you can run with just camber slotting.

Currently, I have toe set at the stock position on the subframe with washers tacked in place (though I'm sure I'm toe'd in more than stock since it's lowered. The toe in isn't causing much tire scrub, but it does cause the back end to wander in the wet. As for camber, I'm currently slotted about 5/8" of an inch with no welding and it has never moved on me. I've checked multiple times in the last 5 years.

as for a magic safety number, I would leave at least 1/4" to 3/8" of plate left on the outside edge of your hole.

Here's a pic of my subframe with 1/2" slots for camber:

[jjgbmw323]

We looked at my Korman prepared DINAN rear subframe, a while ago...when I stillowned my condo
For the newer guys on the board, maybe its time to look again at this.....








I am finally gonna powdercoat it black. From what I heard from the previous owner, this is all you need to
get the wheels spot on straight....

With the 15 x8 RMs in the back, I am going to go with a little negative camber but nothing like what I have now....

[IRideFixed]

jr.... that was exactly the information i was looking for.

i was wondering if the toe was effected by lowering. its much harder to see toe vs camber by eye. my car will be seeing plenty of snow this winter so ill be going ahead and slotting to put the toe back to stock.

[bionicbelly]

I think JR's suggestions are great from a safety standpoint. I used the camber kit from Ireland, and the slots on it only have about 3/8 of material from the top of the slot to the top of the plate, so it sounds like a good figure. My question though, is what are you using the car for? If you are going to autocross, you really shouldn't need to slot it very much at all. you will want in the range of 1-2 degrees negative (depending on how much you can get in the front.)
When I put my kit in, i set the camber to 0, and the thing was so loose in the back, it was almost undriveable.
I have since got it pretty well sorted out with 1.25 degrees front and 1.75 rear. 0 toe in the rear and 1/16 in in the front. (tried toe out, and it felt like s#$%) This gives the car more bite in the front than the rear, and it is easy to bring the rear end around with the trottle, but unless you are on the gas pretty hard, or let off abruptly while turning, the rear stays pretty well planted.

[jrcook320]

thanks for the pics joe. I'll add this thread to the faq, we need more than brief description and a pic.

Remember there's also this thread in the faq:
Ireland Engineering Subframe Kit

[jjgbmw323]

thanks for the pics joe. I'll add this thread to the faq, we need more than brief description and a pic.

Remember there's also this thread in the faq:
Ireland Engineering Subframe Kit

Please do, as I think we could actually reproduce this mod on other subframes and say good riddance to Korman and there 1K price for this.

[jrcook320]

Please do, as I think we could actually reproduce this mod on other subframes and say good riddance to Korman and there 1K price for this.

dude, you can buy the kit from Ireland for around $100 and have it welded on by anyone (including me) for less than the cost of the kit.

[IRideFixed]

dude, you can buy the kit from Ireland for around $100 and have it welded on by anyone (including me) for less than the cost of the kit.

wanna take a small road trip to dayton? i kid, i kid...

[jjgbmw323]

dude, you can buy the kit from Ireland for around $100 and have it welded on by anyone (including me) for less than the cost of the kit.

Of course. I did not pay this for it, but the guy who I got this from did.

[jrcook320]

wanna take a small road trip to dayton? i kid, i kid...

no, but I may be in dayton sometime this fall/winter. If you buy the kit I would be willing to weld it on for you. I charge $20/hr for my time and I guess it would take between 3-4 hours to do a nice job.

You are welcome to drive to Van Wert to drop it off, see my car and chat. It's good to meet local legion members (there aren't many around here). It's an easy 1.5 hour drive.

By the way, I'll be at nelson ledges road course on oct. 16th for a fun day. There may be a few other e21 guys coming, you should try to make it.

[jjgbmw323]

no, but I may be in dayton sometime this fall/winter. If you buy the kit I would be willing to weld it on for you. I charge $20/hr for my time and I guess it would take between 3-4 hours to do a nice job.

You are welcome to drive to Van Wert to drop it off, see my car and chat. It's good to meet local legion members (there aren't many around here). It's an easy 1.5 hour drive.

By the way, I'll be at nelson ledges road course on oct. 16th for a fun day. There may be a few other e21 guys coming, you should try to make it.

OT: Josh thanks for the help with the brakes and the WUR, my car is running now...
to bad you dont go to the show and shine....

Quick question: I know this subframe works with the e21 diff.
If I ever build a 2.9 m20 turbo, can we modify the subframe to accept something like an old 5 series or e30 diff? What would you recommend for diff and rear axels? I have been thinking there is no real good way to supercharge my car, but a 2.9 m20 turbo could be done....

Not to sure if the stock e21 diff and tranny could handle this...

[IRideFixed]

iv thought about supercharging also...

i was thinking of just using the intake side of a turbo and putting it on a pulley. make some brackets and away you go.

[Layne]

iv thought about supercharging also...

i was thinking of just using the intake side of a turbo and putting it on a pulley. make some brackets and away you go.

Won't work. Centrifugal superchargers need a gearbox at the front to increase the speed because they have to run much faster than a belt is capable of turning them.

[IRideFixed]

what if it was a really really tiny pulley?

or large...

[E21Adam]

OT: Josh thanks for the help with the brakes and the WUR, my car is running now...
to bad you dont go to the show and shine....

Quick question: I know this subframe works with the e21 diff.
If I ever build a 2.9 m20 turbo, can we modify the subframe to accept something like an old 5 series or e30 diff? What would you recommend for diff and rear axels? I have been thinking there is no real good way to supercharge my car, but a 2.9 m20 turbo could be done....

Not to sure if the stock e21 diff and tranny could handle this...

Joe,
You could use a Getrag 265 transmission from an e12 or early e24 (later cars like the e28 didn't have the speedo drive) and possibly the driveshaft from one too. Diff out of an e30 sounds like a good plan.

[jrcook320]

Joe, you're right, you'll probably have problems with the e21 diff.

I recently aquired a knife edged s14 crank for my next engine build. I have no immediate plans, but I plan to modify the e21 subframe to accept an e28 or e30 diff. I plan to make a jig so I can modify other subframes for the same treatment.

[jjgbmw323]

Joe, you're right, you'll probably have problems with the e21 diff.

I recently aquired a knife edged s14 crank for my next engine build. I have no immediate plans, but I plan to modify the e21 subframe to accept an e28 or e30 diff. I plan to make a jig so I can modify other subframes for the same treatment.

Let me know what you do for tranny and diff if you do modify them and what rear axles to use.

Josh I was at the show and they told me that the Z3 diff and the e30 diff are the same. Not sure if they are or not.

I read some where that Quaife sold a LSD for our cars, not sure how much power the stock tranny and diff can handle.

I am going to put the 2.9 m20 in - its almost built. Then Later I will save for the Diblas intake for the m20. My future plans someday I will build another 2.9 that is a turbo.

[pommeree]

I read some where that Quaife sold a LSD for our cars, not sure how much power the stock tranny and diff can handle.

Quiafe guts: $1694.95 from Bavauto. P/N 30.309.140

[jjgbmw323]

Quiafe guts: $1694.95 from Bavauto. P/N 30.309.140

I will have to ask about that. I will give Rob Gib a call.

[jrcook320]

Let me know what you do for tranny and diff if you do modify them and what rear axles to use.

Josh I was at the show and they told me that the Z3 diff and the e30 diff are the same. Not sure if they are or not.

I read some where that Quaife sold a LSD for our cars, not sure how much power the stock tranny and diff can handle.

I am going to put the 2.9 m20 in - its almost built. Then Later I will save for the Diblas intake for the m20. My future plans someday I will build another 2.9 that is a turbo.

I'm not worried about the tranny yet. I think it should hold 300-350 hp fine. If not, I'll just swap in a stock e12 265, and maybe a 240mm flywheel and clutch. See adame21's thread on the camparison between the that and the g240/245 tranny's.

The z3 and the e30 use the same diff. There 3 basic diff sizes that bmw uses:
metric-mechanic-differential-booklet.pdf

small 168mm (all 4 cyl bmw's - 02, e21, e30, e36)
medium 188mm (6 cylinder bmws - e30, e36, e28, e34, e24, e23 & z cars) (bavaria's, e12's, and early e24's use the same gear size but the old style side load diff) (e46, e39 use the same gear size but yet another style case)
large 210mm (everything else)

I plan to use a medium case LSD, probably in the 3.45 gear range. I have yet to research what is going to make the most sense for the adapting to the e21 subframe. Probably the e30 is the most available. I am not a fan of the e12 diff because they're hard to find, especially in limited slip.

The quaife will not do anything to make your diff stronger. It is just a replacement for the clutch unit. What will break is the gear set (likely the 168mm ring gear).

I will have to ask about that. I will give Rob Gib a call.

Biggest waste of money you'll ever spend.