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

[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]

I just looked up Latte Dad. Congratulations!

[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.

[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...

[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

[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]

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]

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]

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]

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?

[Vtec?lol]

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

Yeah... HURRY UP AND FINISH!

Awesome stuff.

[Turk]

So... in a bid to create a tubular sub chassis and bracing, we made some Captive nuts and welded them to the chassis rails.




Gearbox mounted now we are strengthening the chassis rails. We are taking the strengthening a few steps further and creating a complete underside reinforcement. 30mm thick wall tubes will line the whole of the outside perimeter of the car. Ie the inner edge of the sills right up to the jacking points.





So with the X brace done we integrated the rear tcase mount into the rest to creat complete rigidity. Its very rigid :)




So the Xbrace conveniently now holds the main gbox mount in place too







So onto the steering,

Made a basic subframe to suspend the steering rack. It IS slight off to one side, but there is actually no way round this atm using ANY bmw rack. So that might be a future mod when we find a rack wil the knuckle further over.






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

[DER E30]

This gon' be such a beast!

[Turk]

Got into gear today...

Basically made the full mounts and mounting points for the engine and tranny.


Off out the new wishbone mount brackets we welded a flat plate which gives us 16mm of clearance for a bit of poly for cushioning. We did consider completely solid mounting it, but have settled half way (ish)




Then we strengthened the floor pan with thick wall tubing. With some welded in thread, we made a removable centre mount area to hook the t-case poly bush in a very 'Sturdy' fashion!








The transmission tunnel is holding stuff together for now, However it will be going shortly to be replaced by a nice new more spacious affair.

Also in the future a roll cage will be fitted so we are making our lives easier by doing some work now.

The supercharger should be located where the AC compressor would go. However with the engine mount in the eay we don't know if that will work (yet).

More soon!

[Turk]

ahhh adem, this is where you've been hiding:D

whats happening with this project ?

It under way Glenn, car is currently having a proper roll cage installed :) The idea being it will stiffen the chassis and also create stronger mounting points for the engine, box and t-case.

Once the car is back, just need to finish rebuilding the engine, new bearings, chains, headgaskets, etc etc. fingers crossed the tcase will withstand the punishment :)