differential - United Bimmer Community

**jestone** · 12-10-2005, 04:08 PM

Hello newbie here. I recently got a 84 318i for free!!!!!! Imagine someone throwing out a perfectly good car. Well not perfect, but driveable. I was wondering about this cars differential. Is the 318i and the 325i diff the same or dififferent????? I want to put a 6 in it, as it only has a 4 banger. Any help would be appreciated. Thanks

**komodo** · 12-10-2005, 04:13 PM

I don't remember the ratio, but I'm pretty sure on e30's is models were LSD and i models were open... someone else will probably reply knowing more than me, haha.

Either way, welcome to UB!

**bex325** · 12-10-2005, 09:02 PM

alrighty, let me step in here and provide a bit of info on e30 diffs.

the early model 318s with the m10 have a different rear subframe than the 6-cylinder models... smaller, weaker etc. I cant recall off the top of my head exactly which ratios they came with, but the point is that the diffs are actually smaller. The best thing to do would be to swap the rear subframe off a 6-cylinder e30 to gain the larger case diff and dicsc brakes, although since you are going to be replacing everything already why not throw in the rear subframe off a z3 or a e36/5 (318ti) to get 5-lug hubs. I also believe that the front struts are of a smaller diameter than the 6-cylinder models... somehting to keep in mind.

personally, i would like to buy an early 318i and a) carb the m10 or b) turbo it. the light weight would make it a beast and the m10 is a tough engine.

Good luck with the car and welcome to the e30 world!

**xsperf** · 12-10-2005, 09:27 PM

wouldnt that be an e21? and arent the engine mounts for the 4 and the 6 a little different?

**komodo** · 12-10-2005, 10:39 PM

Also congrats on getting it for free.

**bex325** · 12-11-2005, 12:16 AM

Quote:

Originally Posted by xsperf

wouldnt that be an e21? and arent the engine mounts for the 4 and the 6 a little different?

nope tis an e30. e30 production started in 82, but i think they officially came to North America as 84's.

In terms of the Engine swap, you will need the engine, tranny, driveshaft, rear subframe assembly, etc. Motor mounts are different among other things.