BMW Compact Build

Got over to work on the car last night. With Scott's help we got measurements for the driveshaft, but we'll leave final install work until the driveshaft is in hand.

Also got the helper springs installed on all 4 shocks last night. On the rears I used adapterish things to hold the two springs together. The fronts were even easier, as with the drop required, I just put them at the bottom, and the main spring still sits around the lower mount, so there's no chance of the springs moving out of allignment or getting hung up on the lip of the spring seat.



Hopefully lots more progress this weekend.

Dave

Quote
DaveK



Hopefully lots more progress this weekend.

Dave

i would think the helper at that location would potentially be subject to more rock/gravel abuse than at the top. also would think it would have been better to put on top as then its not trying to lift the whole spring, just keep it in place and push it down (not lift the whole thing when uncompressed).

just my thoughts.

I can't tell from the picture, is there one of those little mini double sided spring perch things the keep the ends together? If you dont run those, I would probably run the helpers at the side with the BIG aluminum perch John machines, to keep them inline. Otherwise, I would be afraid of them sliding around and the helper getting cocked. But using the mini perch things would be my first suggestion.

Quote
Mark
i would think the helper at that location would potentially be subject to more rock/gravel abuse than at the top. also would think it would have been better to put on top as then its not trying to lift the whole spring, just keep it in place and push it down (not lift the whole thing when uncompressed).

I'd have preferred both to be mounted at the top, but the hats on the top of the front ones has a lip that's ~3/4" tall. The rears is just about 1/4", so when the helper spring compressess, it fully fills that void. Basically, on the fronts, there's not enough room to put those spring perch/separators in-between the springs because that would bind up agains the top hat before the spring gets a chance to lay flat.

Only running the spring separators on the rears, those little grey nylon things - the fronts aren't dropped enough that the main spring could get cocked on the lower part of the perch. You can kinda see what I'm talking about, b/c you can see the blue machined spring perch pokes up higher than the bottom edge of the main spring.

FWIW, on my Ohlins...helpers are on the bottom.

Dave

Got some time to work on the BMW last night. Big thanks to Scott M. for helping out!!

Here's Scott beefing up the rear trailing arms:



The finished product:



All I need now is that 4.56 diff.

Dave

Fixed it for ya:

Quote
DaveK
All I need now is that 5.1 diff.

Dave

Quote
wvonkessler
Fixed it for ya:

Quote
DaveK
All I need now is that 5.1 diff.

Dave

Hey! He has some tractor 3,0 thing, not a rev-monster.
He's in the Wilda Väst with all them wide open spaces.
5,1 would kill top speed---specially if it only really revs to 4800 rpm

Horses for courses, Herr von K.

Hey did you get the Peee Em asking for your telly-pone nummer?



Edited 1 time(s). Last edit at 03/04/2011 09:27PM by john vanlandingham.

Quote
john vanlandingham

Quote
wvonkessler
Fixed it for ya:

Quote
DaveK
All I need now is that 5.1 diff.

Dave

Hey! He has some tractor 3,0 thing, not a rev-monster.
He's in the Wilda Väst with all them wide open spaces.
5,1 would kill top speed---specially if it only really revs to 4800 rpm

The problem is that the BMW gearboxes have shitty ratios. 5th is 1:1 so with the 5.1 it would top out at 105 at 7000rpms. The 4.56 will do 117mph, which is perfect, but that 1st gear is lame to even post!

"Spec M3s" at the tracks out here in Colorado will top out around 120mph, so I was shooting for a little bit of a compromise on top end. I was orig. leaning to getting the 4.88, but that was when I thought the redline was 7500. Don't see any need to really rev the crap out of the motor if its over 200 ft/lbs by 2500rpm.

Of course the other great thing about the supra diff conversion is that I can go out and get another one from a junk yard, pick a new R&P ratio, get it rebuilt, and have it in the car for ~$500 or less.

Dave

More fab pics!

First up is me doing a bit of grinding on the rear mounts for the diff:



Here's the notches cut and one of the new tubes fitted into place:



I'll be back at it tomorrow trying to get that project finished off.

BTW - Sean, if you're reading this - please call JVL about that supra diff...........I need it next week or I'm going to miss an event.

Dave



Edited 1 time(s). Last edit at 03/11/2011 10:13PM by DaveK.

I dropped the spacer off wednesday, and he said he should have it done today. I would guess we can get it in the mail Monday or Tuesday. I will call him in the AM.

Thanks Sean! Guessing if it could get dropped off Monday that normal shipping would get it to Denver by Friday.


Dave

Hey Sean - wondering if you heard back from the diff guy? Sorry to pester you on here, I don't have any other contact info for you. Thanks for helping out!!!


In other news, got the E90 inner tie rods swapped in (though they might be a touch too long), started back in on the exhaust system (mufflers - booooo!), and hope to have our vinyl guy come over later this week.

-sunroof panel welded in place
-rear diff mounts
-bleed brakes
-bleed clutch
-fill tansmission
-fill power steering
-wire up radiator fan
-fab exhaust from cat-back
-fab skidplate mounts
-allignment
-load on trailer
-shake it down

Dave

Quote
DaveK
hope to have our vinyl guy come over later this week.

Glad to hear you've got the important part planned out.

If it makes you feel better, my oil leak is still there. Damn o-ring!

Call me dave. 425478 zero two niner zero