E34 525ix info

[The Dark Side of Will]

you can't really flip the mount arms but maybe I could use different holes.. the mount arms will be about 1.375" too far forward (based off current measurements and my original mockup), so maybe knowing that, different mount arms could work (I have one e36 arm to test)

I was referring to flipping the rubber mounts around between the towers and arms.

[nando]

The photos made it look like they wouldn't fit, but it's also hard to tell from the photo without mounts in between the arms and towers.
Those arms might work just by flipping the mounts and drilling a new hole in the towers...

Also, can you take a photo straight on from the left? It looks like tilting the rack forward to clear the E53 diff would hit the E34 mount arm.

just did some more test fitment - I'm having some rack clearance issues as well.

took out the snubber, but the oil pan/diff hit the steering rack. I need it to move another 1" forward for this to fit.. even if I wanted to leave it that way, the head wouldn't clear the firewall being 1" back.

Just for kicks I test fitted with an E46 xi rack. actually, it clears a bit better (especially the diff, might want to give that some thought) but the fittings for the pressure lines hit the engine mount.

anyway, I'll put the E30 rack back in with the E34 mount arm and take a pic from the left for you.

I'm not really sure how to get that extra 1". perhaps modifying the oil pan, but the diff would still hit. maybe an entirely different steering rack would be the way to go.. anyone tested how a RWD E36 rack sits on an E30 subframe?

[nando]

I'm pretty sure the snubber wouldn't fit because it was about 1/8" away with the mount arms centered over the engine mount holes on the subframe. Based on your measurements I'd have to move the sump forward 1.25".

I can definitely get another pic straight from the left, I just have to piece it back together again. I might try this time with the diff installed on the oil pan (it's just grimey and I don't want to touch it).

you can't really flip the mount arms but maybe I could use different holes.. the mount arms will be about 1.375" too far forward (based off current measurements and my original mockup), so maybe knowing that, different mount arms could work (I have one e36 arm to test)

[The Dark Side of Will]

now that I know where the axle centerline is supposed to be, I'll remove the snubber thing and see how the mount arms align. they're going to be too far forward for sure. they're also too narrow..

The photos made it look like they wouldn't fit, but it's also hard to tell from the photo without mounts in between the arms and towers.
Those arms might work just by flipping the mounts and drilling a new hole in the towers...

Also, can you take a photo straight on from the left? It looks like tilting the rack forward to clear the E53 diff would hit the E34 mount arm.

[The Dark Side of Will]

Ah ok, so thats pretty much the only problem? (except drive shafts etc)
Hmm i think i have to get my hands on a E53 oil pan :)
3.07 would be better than 3.38!

I'm doing a 32V swap with S62... so I'm VERY concerned about clearance between the firewall and the back of the left cylinder head. So for me the fore/aft distance between the back of the crossmember and the pedal box area of the firewall is very important.

All the measurements I can take right now tell me it will *probably* fit but will be REALLY REALLY REALLY close.

[nando]

Great! Thanks!

So if the E34 pan works, the E53 6 cylinder pan will also fit. Of course the E53 pan will take a U-jointed driveshaft, but I don't think that's a big deal.

The axle centerlines are a non-issue UNLESS the excess angle on the outer is such that it runs out of travel before the steering rack does... but I'm guessing you'd have to move the inner joint a LOT for that to happen.

I don't think any of the alternative pans can use the snubber on the crossmember.

I'll check the E39 V8 arms when I get my engine on the stand... soon.

yeah, possibly the E53 pan could be an alternative if you can work out the rack issues. the E34 pan clears the rack no problem. although I haven't tested with the diff mounted it doesn't look like it obviously hits.

now that I know where the axle centerline is supposed to be, I'll remove the snubber thing and see how the mount arms align. they're going to be too far forward for sure. they're also too narrow..

I would like to figure out a way to keep a snubber of some sort. I think it's important given the extra stress the ix mounts see. also, there are built-in rubber bumper things on the ix engine mounts for side to side movement. I never realized what they were until recently, pretty clever. unfortunately, they're NLA. :(

I believe the E39 6cyl mount arms will be much too far back. maybe I can find one to test fit, I could be wrong.

the lynch pin in my plan is the engine/trans must be in the same position as the original M20, or it won't work. I think it can be done using 100% stock parts (aside from engine mount arms).

Got the same measurments as Nando.

What trans do you want?

Cool. I measured with a yardstick I had laying around, it might not be exactly 11 3/8" but it's close. and if you take the 5/8" change over a ~24" long shaft, the angle change is pretty small.

as far as the trans, I'll be using a Getrag 260. part of it should be arriving from Germany sometime early next year, the other half I have to source stateside somewhere. the plan right now is to send it to be built by geardrive.

[Nisse Järnet]

There is a clearance problem. I'll know more when I get my crossmember bolted up to my engine. However, it looks like the steering rack spool valve assembly bumps into the E53 diff.

I am reasonably sure this can be solved by tilting the steering rack "up" so that the pinion shaft is closer to vertical. I have a solid idea on how to do this, but I need to get some machine shop time to make it happen.

Ah ok, so thats pretty much the only problem? (except drive shafts etc)
Hmm i think i have to get my hands on a E53 oil pan :)
3.07 would be better than 3.38!

[The Dark Side of Will]

Haha i dont, google converted them for me :)

Isnt there a clearence issue with the E53 parts, diff hitting the steering rack servo fittings or something?
I got a E53 3.07 front diff but no E53 pan yet, hope i can use it and pair it with my 210 3.07 rear :)

There is a clearance problem. I'll know more when I get my crossmember bolted up to my engine. However, it looks like the steering rack spool valve assembly bumps into the E53 diff.

I am reasonably sure this can be solved by tilting the steering rack "up" so that the pinion shaft is closer to vertical. I have a solid idea on how to do this, but I need to get some machine shop time to make it happen.

[Nisse Järnet]

Great! Thanks!





So if the E34 pan works, the E53 6 cylinder pan will also fit. Of course the E53 pan will take a U-jointed driveshaft, but I don't think that's a big deal.

The axle centerlines are a non-issue UNLESS the excess angle on the outer is such that it runs out of travel before the steering rack does... but I'm guessing you'd have to move the inner joint a LOT for that to happen.

I don't think any of the alternative pans can use the snubber on the crossmember.

I'll check the E39 V8 arms when I get my engine on the stand... soon.



Thanks! I didn't know you spoke inches

Haha i dont, google converted them for me :)

Isnt there a clearence issue with the E53 parts, diff hitting the steering rack servo fittings or something?
I got a E53 3.07 front diff but no E53 pan yet, hope i can use it and pair it with my 210 3.07 rear :)

[The Dark Side of Will]

Great! Thanks!

Just checked..

BH to CL of axle:
~11 3/8"
BH to front of sump:
15 1/4"

E53 I6 pan:
BH to axle CL: 11 1/4"
BH to sump: 15"

So if the E34 pan works, the E53 6 cylinder pan will also fit. Of course the E53 pan will take a U-jointed driveshaft, but I don't think that's a big deal.

The axle centerlines are a non-issue UNLESS the excess angle on the outer is such that it runs out of travel before the steering rack does... but I'm guessing you'd have to move the inner joint a LOT for that to happen.

I don't think any of the alternative pans can use the snubber on the crossmember.

I'll check the E39 V8 arms when I get my engine on the stand... soon.

Got the same measurments as Nando.

Thanks! I didn't know you spoke inches

[Nisse Järnet]

Got the same measurments as Nando.

Just checked..

BH to CL of axle:
~11 3/8"
BH to front of sump:
15 1/4"

I think we figured out on E30tech from flyboyx's posts that the E34 axle centerline was further forward by some amount, I've just never had an E30 pan to compare mine to. I don't think 5/8" difference in axle centerlines is a show stopper in any case.

The sump looks like it can still work fine but I won't be able to use the engine stopper thing as-is.

I did some additional mock ups with some E30 ix engine mounts I picked up a while back. I'm not sure if using any factory BMW mount arms is really going to be worth it - maybe just fabricating some out of steel would be better/simpler. sometime next year I should finally have a transmission to do mock ups with.

I haven't confirmed but I don't think E39 mount arms would work either.

What trans do you want?

[nando]

"Guy" = me.



I wish I'd seen these photos a while ago... I didn't realize that the E34 mount arms were so close... Any idea how the E39 mount arms compare to the E34 mount arms?
I believe the E34 uses the same mount locations for V8 and I6. The E39 uses different front subframes for the V8 and I6. I don't know if the V8 mount locations carry over from the E34 or not.

Have you compared the E34 oil pan measurements to these?

http://www.e30tech.com/forum/showpost.php?p=1351129&postcount=553

I'd like to see that info for the E34 pan.

Just checked..

BH to CL of axle:
~11 3/8"
BH to front of sump:
15 1/4"

I think we figured out on E30tech from flyboyx's posts that the E34 axle centerline was further forward by some amount, I've just never had an E30 pan to compare mine to. I don't think 5/8" difference in axle centerlines is a show stopper in any case.

The sump looks like it can still work fine but I won't be able to use the engine stopper thing as-is.

I did some additional mock ups with some E30 ix engine mounts I picked up a while back. I'm not sure if using any factory BMW mount arms is really going to be worth it - maybe just fabricating some out of steel would be better/simpler. sometime next year I should finally have a transmission to do mock ups with.

I haven't confirmed but I don't think E39 mount arms would work either.

[The Dark Side of Will]

Thanks!

Also, check this thread out: http://www.e30tech.com/forum/showthread.php?t=116657

[Nisse Järnet]

I can measure my E34 IX pan when i have time :)

[The Dark Side of Will]

a guy on E30tech brought up a good point - you could make your own mount "towers", which are the brackets that bolt to the subframe, which sandwich the mounts to the mount arms themselves. you could make them so the center hole was 2" further forward and then RWD E34 mount arms would work.

"Guy" = me.

so my initial assessment of RWD E34 mount arms not fitting appears to be wrong - they line up with the ix mount towers pretty much dead on! I have a loosely fit together mockup sitting on the floor. No transmission, so I can't confirm yet that the engine will be in the "stock" position:






when I have a transmission I can check the relative location of the transfercase/transmission to the subframe. right now there's a very small gap between the rubber "bump stops" on the subframe and the oil pan. I can't remember if they're supposed to fit snug, or if there's supposed to be a gap - but with it snug up, the mounts are a tiny bit too far forward. these are also original 20 year old rubber bits so they're probably a bit deformed though.

other unanswered questions are mounting height of the engine and whether the mount arms actually reach the mount supports. but it looks like the geometry is at least correct, spacers could possibly be used to account for the rest.

I wish I'd seen these photos a while ago... I didn't realize that the E34 mount arms were so close... Any idea how the E39 mount arms compare to the E34 mount arms?
I believe the E34 uses the same mount locations for V8 and I6. The E39 uses different front subframes for the V8 and I6. I don't know if the V8 mount locations carry over from the E34 or not.

Have you compared the E34 oil pan measurements to these?

http://www.e30tech.com/forum/showpost.php?p=1351129&postcount=553

E30 pan:
Bellhousing face to axle centerline: 10 1/8"
Bellhousing face to front of sump: 14"

E53 V8 pan:
BH face to axle CL: 10 3/4"
BH face to front of sump: 14 5/8"

E53 I6 pan:
BH to axle CL: 11 1/4"
BH to sump: 15"

For both the E53 pans, the block bolt pattern extends ~ 1/2" beyond the bellhousing pattern.
While the space required for the E53 pans is greater than that for the E30 pan, I believe that either of the E53 pans could be accomodated in the E30 body by removing the "snubber" mount on the back side of the crossmember. This frees up an additional 1"+ in which to fit the sump, without moving the bellhousing face back.

I'd like to see that info for the E34 pan.