E30 M3 S62 Build - Loads of queries about 4x4 drivtrains

[Vtec?lol]

SO, thats it for today... any ideas or suggestions?

Yeah... HURRY UP AND FINISH!

Awesome stuff.

[The Dark Side of Will]

With the rack offset, you're going to have WEIRD bump steer, assuming that the rack was the right width for your control arm mounts to begin with.

Can you tilt it forward so that the pinion is more upright in order to clear the diff?

[Turk]

There are literally mm's between the diff and knuckle Will, even tilting back doesnt resolve as it forces the rack forward. Only remaining option is to space the rack out further and alter hight. But then the oil sprocket casting in the sump causes issues, not to mention arm/rod angles, ackerman, and even more bump steer.

You might want to consider ditching the lhd rack like we did and use a rhd rack flipped round. It puts the gear side of the knuckle on front of the rack and the pas fittings too!!! Much easier. Mounting holes work great on a custom subframe too. However the hunt has begun for a longer rack!

We have lost 30mm from one arm and the other has gained it. With some nice stiff coilovers and minimal travel, bump steer kit it might not be horrific. But as always with these projects we need to start somewhere, test, remake etc etc.

Faffing about with steering atm. more to come soon!!!

[The Dark Side of Will]

Can you tilt it forward so that the pinion is more upright in order to clear the diff?

There are literally mm's between the diff and knuckle Will, even tilting back doesnt resolve as it forces the rack forward.

I didn't say tilt it back...

[Turk]

we're on the same page, 'Back' as in knuckle upright. Like i say ghaving changed rack to flipped rhd there are now other considerations and various mouldings etc. Lhd rack has far more issues.

[The Dark Side of Will]

Yeah, "back"...as in "forward"--got it! ;)

Better look into measuring bump steer... and don't final weld anything until the bump steer has been worked out.

I think the stock iX rack will work for me with the mods I intend to do... I just need to get my engine on the stand so I can mock up my spare front crossmember with the rack.

[Turk]

Great, dont forget to post pics when you're winning :) There must be a nicer solution to this crap. Not looking forward to swapping the steering internals over

[turbotarzan]

OP is not using it because he's in England.

*I* am. http://www.e30tech.com/forum/showpos...&postcount=340

I have a TR6060 from a 2010 Camaro. I'll be using:
- Bellhousing from a '98 540i automatic
- Custom adapter plate and HTOB mount
- Transmission front plate from a C6 ('05-'13) Corvette
- Main case and guts from aforementioned Camaro
- Custom length output shaft
- Rear housing from a C5 ('97-'04) Corvette
- Custom adapter plate
- Borg Warner 4472 T-case from a Syclone/Typhoon/Bravada/Astrovan, etc.

Back again after what we in scandyland call being a Latté Dad.
I looked into the BW 4472, nasty little TC, isn't it?:)
But where can I find an overhaul kit for it if I buy one? (all AWD Astros etc. in scandyland have been to the sun and back when it comes to miles)
Well, I guess the viscous coupling is the most important, everything else can be found/made elsewhere.

Also, I'm a bit drunk because Finland lost to Sweden today in hockey so I'm just gonna go ahead and post this :hitler: little fu*ker to all you swedes out there... good game tho. Good game...

[The Dark Side of Will]

I'm not sure about an overhaul kit, but there are plenty of places that will sell you a rebuilt unit. If you press them, they will probably sell you a kit.
(e.g. http://www.monstertransmission.com/BW-4472_c_3842.html )
If you google "Borg Warner 4472", most of the results are rebuilders.

Be careful about the difference between the 1372 and the 4472. A lot of the rebuilders lump them together because they're very similar. I *think* that the 4472 has a 32 spline rear output and a larger front output flange while the 1372 has a 27 spline rear output and a smaller front output flange, but I'm not entirely sure. However, the rebuilder above offers all four combinations of rear and front outputs...
I'm not sure about a specific rule like certain models got one or there was a production change at a specific date.

I was under the impression that the VC's in these units hardly ever go bad.

[The Dark Side of Will]

I just looked up Latte Dad. Congratulations!

[DER E30]

With the rack offset, you're going to have WEIRD bump steer, assuming that the rack was the right width for your control arm mounts to begin with.

Can you tilt it forward so that the pinion is more upright in order to clear the diff?

I should think that you could offset the rack housing a little and not get weird bump steer, as long as the actual tie rods are the same length from pivot to end... My thought is that the rack itself isn't where the tie rod "arms" pivot on, and if the joints are the same length from the tie rod ends, there wouldn't really be a difference... Of course it would still have uneven "lock to lock."

[The Dark Side of Will]

True...

But if you locked the wheel straight ahead and then set the toe, it would end up with bump steer.

[DER E30]

But if the moving parts of the rack are centered to the car and not to the housing, would it make a difference? I know on my truck I measured both tie rod lengths and equalized them when setting the toe. That way the housing isn't necessarily centered (pretty close though), but the components are, then I put the steering wheel on, and all was well. Of course that gives unequal turning radii for parallel parking and such... But I didn't really care as I usually drive with the wheel fairly straight anyway.

Pushing the rack over is probably not good if you drift at full lock though! Having more lock drifting left vs right would suck...

I'm not saying that it is ideal, just that when confronted with the choice of "push the housing over a few MM", or do crazy fab work to everything, it might not be the end of the world.

[The Dark Side of Will]

GM stuff tends to have the wheel keyed... not sure if BMW stuff does or not.

If the wheel's keyed and you set it straight, then the moving parts of the rack will be centered on the housing.

[zumjosh]

My brother and I salute you. Keep up the fantastic work.