Teach me about ITR 325's

[Z3_GoCar]

Josh,

Something completly analouguos, that I know about. Does the TIS for the Z3 have the factory proceedure for fixing a cracked differential mount? I know that I've seen several where the dealer will weld a second mount over the first. However, it seems the dealer has to bring in an rep to tell them how to perform the repair, thus avoiding the documentation and resulting liability if something goes wrong with the repair. Maybe it's a similar kind of situation... non-documented dealer/factory repairs.

James

[JoshS]

Josh,

Something completly analouguos, that I know about. Does the TIS for the Z3 have the factory proceedure for fixing a cracked differential mount? I know that I've seen several where the dealer will weld a second mount over the first. However, it seems the dealer has to bring in an rep to tell them how to perform the repair, thus avoiding the documentation and resulting liability if something goes wrong with the repair. Maybe it's a similar kind of situation... non-documented dealer/factory repairs.

James

I've never seen any acknowledgement by BMW for the diff mount/trunk floor problem, just like I've never seen anything for the E36 problem.

Therefore, such a dealer-installed repair would not be legal in IT, even if a verbal agreement with a BMWNA employee allowed BMWNA to pay for the repair.

[Z3_GoCar]

I've never seen any acknowledgement by BMW for the diff mount/trunk floor problem, just like I've never seen anything for the E36 problem.

Therefore, such a dealer-installed repair would not be legal in IT, even if a verbal agreement with a BMWNA employee allowed BMWNA to pay for the repair.

Just because the GCR mandates that the manufactures provide XYZ (in this case it's a document stating dealer repair methods) to a racer doesn't mean that the manufacturer will. In this case of drastice chassis repairs, there is probably legal liability reasons for the absense of such a document along with proprietary reasons. Just because the document doesn't exist doesn't means it strictly illegal either.

[Andy Bettencourt]

Just because the document doesn't exist doesn't means it strictly illegal either.

Then how do you know how to perform the repair?

[Greg Amy]

Just because the document doesn't exist doesn't means it strictly illegal either.

Actually, James, per the explicit rules it means exactly that....



GA

[lateapex911]

Wow...never knew THIS was where the rules and regs soap opera went!

For the record, Air bushings. It is said that RX-7s (early cars like mine), when lowered will bind the rear axle and destroy U joints. That's because the stock upper trailing arm pulls the axle forward at teh top at that point in it's travel. The rules allow the addition of traction bars, and with a properly designed traction bar, one can do what you wouldn't normally think of: use really soft bushings as opposed to the typical hard replacements, in the upper trailing arms. This allows the axle to rise and fall without twisting forward, and removes the binding.

Now, I haven't crawled under anyone's RX-7 in a long long time, but rumour has it that not only are the bushings just not replaced at all, but the upper trailing arms are just left off certain cars. Honestly, it wouldn't surprise me, but, at the front, my bet is all RX-7s are legal. Mine runs hard foam in the upper trailing arm bushing locations. (I can't imagine the racket air would create if used as a bushing!)

Air bushings? Silly boys!

[Knestis]

A bushing made of closed-cell foam would in fact be a composite of an elastic material and air. Not a problem under the current regime. Removing the [whatever] altogether would be OK if the rule allowed replacement or "removal." Remember some rules (e.g., the sway bar allowance) didn't actually allow that, although in this example the language was changed.

We should all - myself included - read Gary's really good point a few more times.

K