1983 E21 316 auto gearbox

[steveE21]

Hi everyone,

I am now a BMW E21 owner for the second time. I originally owned a 320 but had to sell it, a sad day indeed.

But have now got myself a 1983 316 with the 3 speed auto box. The car is in really good condition (featured in BMW Car mag in Jan this year!), the interior is near perfect, and the body work has a few bits of rust to sort out but nothing too nasty at all. All in all a very well cared for car.

The gearbox works well and the kick down happens as it should. However, I was thinking about maybe acquiring a couple more gears from somewhere, 70mph at around 4200rpm is entertaining, but a little noisy and fuel consuming!

I have read that you can "swap" the ZF 3 HP 22 for a ZF 4 HP 22 (which has overdrive?) thus solving the problem. Or is there anything else I could consider, any thoughts? I want to keep it an automatic as I like the lazy drive to work!

Any help or thoughts gratefully received.

Steve

[unixnerd]

Swapping the 3 for the 4 would be the best idea. Your box has mechanical kickdown and clearly you'll want the same from the new box. The only 4's that don't have mechanical kickdown are easily identified as the cars have the 1-2-3/S/E switch near the gear lever.

Also, not all 4's have the same gear ratios. 3rd (direct) and 4th (0.81:1 overdrive) will be the same but there was a little variation in 1st and 2nd ratios. A box from a four cylinder e30 would likely be the best choice.

Nice car I have a model of an orange E21 316 in my bookcase.

I love than M10 engine, bullet proof and there's so many tasteful upgrades for it. But I imagine you plane to keep it fairly stock?

I had an M10 1.8 on my first BMW, a 1988 E30 316. It was a nice engine but the horrid Pierburg carb let it down. A Weber conversion lets out a good bit more power and can even improve economy!

[unixnerd]

One other wee thing. I have a sneeky feeling the 4 speed box might be a bit longer, I'm sure I read something about that once. So you might need to shorten the driveshaft.

I could be wrong, I'd be interested to find out if anyone knows for sure.

[steveE21]

Thanks for the info and quick reply, very useful indeed. I will start the hunt...

This looks interesting:

http://cgi.ebay.co.uk/E30-318i-auto-gea ... 3efdd2a321

I am very lucky as my 316 already has a Weber carb fitted, and also it had a new M10 engine at 70000mls fitted by BMW (not sure how anyone managed to break one!!), and its only done 112000.

[Adrian678]

Thanks for this links.
I'm also very lucky to get this one out,


howtodealwithdepression.org

[Marshaswig]

In the 07 models, I remember people complaining before about the auto unlock feature and then GM came up with a computer update - flash non-reversible to NOT unlock when shifting to park.
I was thinking the later and newer models would already have the option through DIC?.