will E34 6MT 525ix transmission bolt up to 1991 E30 325ix - m20b25

[nando]

Ok, s50 changes everything, in that case 525ix parts make the most sense, especially for the front diff. Ill reply in more detail in the morning when im not on a phone.

[e30ixBoost]

The E34 has a ZF310/320 5-speed, not a 6 speed. It will bolt up to the M20 engine but the E30 transfercase won't bolt to the E34 ix trans mount, and the angle will be wrong on an M20 anyway so the front driveshaft won't align with the front diff ....

wow you are the man thank you very much for that well formated straight forward and to the point information.

concurrently from the information gathered in your post and if possible to pick your brain some more, ill explain my situation further so it may help to speed things along

i have a 1991 BMW 325 ix 4 door, 5 speed manual

i am looking forward to either boosting it or most most likely now a euro S50 swap

i personally will not be doing the swap, i will be in charge of gathering all the parts, and presenting a small booklet of information and or guide lines to howto's for the shop in order to ease and help speed up their work.

that said, my questions are

pertaining to a european evo 3.2L S50b32 engine, i read its externally the same as the American however internally and electronically it differs, that said ... the franken-oil pan method seems to me as the most cost effective way to do a s50 swap

will the euro S50 engine bolt up to my current american M20 transmission ? if so which clutch parts would i use euro/american?
if not will a euro s50 need a euro m20 transmission, will that bolt up to the american 325ix transfercase ?

are the engine mounts in the same place ?

any difference because of LHD vs RHD which would cause a hassle ?

electronics wise differences or hassles using a euro S50 ?

would leaving the 10* angle be a possibility or will the front drive shaft no longer pass through the oil pan ?

will leaving the engine at said angle require custom fabrications or vise versa ?

since euro M50s are cheap how hard would it be to swap in euro S50 parts ?

if M50 is used and bored out will the block erode cause of the low sulfur fuel ? is a darton sleeve a fix ?

also the reason i choose the euro S50 was because of power/torque ... AFAIK it requires the least of custom fabrication ...

what would the difference be or would it be simpler to use the american S54 engine as its loosely in the same power range ?
If so any issues with the spacing of the radiator or using the dash/E30 electronics after a VANOS remove will be present ?
(the IX must be functional and im really not looking toward a s54 swap as a turbo m20 would be more economical)

and anything else that i have left out or missed which is of use or help

[nando]

The E34 has a ZF310/320 5-speed, not a 6 speed. It will bolt up to the M20 engine but the E30 transfercase won't bolt to the E34 ix trans mount, and the angle will be wrong on an M20 anyway so the front driveshaft won't align with the front diff.

You can't swap the E34 oil pan onto an M20. the angle is 10* too much. the E30 ix oil pump won't work either.

To use the E34 front diff you need the E34 oil pan, *and* both front E34 CV shafts. the E34 shafts are rare as hell to find, especially in good condition, and they're expensive. I have a pair, they cost me an arm and a leg too. Also they need some minor modification to work in the E30's front hubs (abs rings need swapped and a step needs to be machined into the face of the outter joints). You have to use E34 front hub nuts.

you'd also need a matching 3.38 rear diff with a VC, and it'd have to be custom built. there is only one ratio that works in the E34 front diff, and it's 3.38. the E46 and later use the same type 168mm ring and pinion in the front diff but the parts won't fit without extensive customization. and in the end with the ZF and 3.38 your gearing is basically the same as the Getrag 260 and a 4.10, so there's no gearing advantage.

The E30 transfercase is better than the E34 transfercase in several ways. I don't know where you saw that the E30 TC/chain is a weak point, because it's not (but it is common internet nonsense). the weakest point on the E30 is the front diff. it's a type 168 also but everything inside is much smaller than the E34.

both the E34 and E30 have chains in their transfercases, they're both manufactured by ZF. essentially they're the same except the E34 has a electric lock while the E30 has a VC. The people I talked to about it in europe say the lock in the E34 transfercase isn't great for performance, also if it wears out you have to buy a whole new TC as you can't buy the lock seperately like you can a VC. The E34 lock requires the entire ABS system swapped over, all the electronics, and also it remains unlocked at higher speeds (the VC *always* works).

other parts you'd need: E34 ix shift console (which has to be shortened). custom selector rod (unsure of length difference between ZF and getrag, but *hopefully* the ZF is shorter). Custom adapter plate to mount the E30 TC to an E34 ix transmission (has to be located in exactly the same place as it was stock).

It'd be a good idea to get lengthened front driveshaft splines, or some how use parts of an E46 front driveshaft to mate to the E30 transfercase and E34 3-bolt front diff flange.

some things that do work out nicely, the E30 TC and ZF trans both use a 96mm flex disk, the E30 and E34 front diff both use the same size flex disc (get one from an E53 X5 or use an E30 rear flex disc, it's thicker/stronger).

the basic answer to the question of using it with an m20 is flatly, no. if you're going to do all the work to use E34 parts, you're not going to want to waste it on an M20. It will probably cost you about $3,000-5,000, realistically, to do an entire E34 drivetrain swap, and then it will make way more sense to do a 24v engine that is meant to work with.

another final hurdle to this is finding, and shipping, all these parts from europe. it's not going to be cheap. I lucked out on a few parts and also you can buy the rear cover of the E34 ix trans from BMW brand new (don't know how many they have left, mine was obviously sitting in a back room somewhere for the last 20 years). But you still have to buy a ZF in the states and rebuild it with the E34 ix rear cover, although I'd bet it'll be cheaper and better than shipping a whole transmission from germany to the USA (which will likely be worn out, oh yeah, the germans don't take care of their old cars).

[e30ixBoost]

your absolutely correct on that, any differences in lengths between the two transmissions, or a varied mounting angle would require a custom propeller shaft to be manufactured. This cost would not be worth undertaking

i am open to interchanging the 525ix and 325ix structures if need be ... depending on what it may occur (for example enhanced engine or better structured AWD infrastructure)

[Dirty325ix]

if the transmission does bolt right to the engine and I'm not saying it will than you wouldn't have to worry about the oil pan or front diff but I could see problems lining the front drive shaft up with the new transfer case

[e30ixBoost]

that thread didnt answer any of my questions he used stock drive train .. and only mentioned he had reinforced drive train but no details given ...

[e30ixBoost]

thank you ill read up on that thread, i understand the weak points of the E30 ix chain driven transfer box, the front differential / drive axle

im sure down the road we will be able to figure something out

the car was specifically purchased iX for a reason :)

however before we get the ball rolling and money is spent, it would be nice to know of all other options and or solutions that are on the table, money is obviously a factor here - however it would be wiser to invest into the AWD drive train now, then to discover down the road a totally viable money logistical solution was available .

also we are already 2 weeks into the research phase, so the idea is nothing new, i have many saved bookmarks and jot notes , however it is best to clarify and double check as much as humanly possible :)

[downforce22]

you may want to look at this iX and his build thread before you get all gung-ho on 900 HP in an iX.You better have some spare axles, trannys, and diffs.

http://www.r3vlimited.com/board/showthread.php?t=180631

[e30ixBoost]

as the tittle is asking ..without any modification ?

if so am also wondering if transfer box from a 5 MT 325ix will bolt up to the 525ix transmission without modification ?

separate to that i know the E30 m20b25 has a funky oil pan and the front drive shaft goes through it, does this mean that swapping the M50B25 in place with the transmission and transfer box will need entire new front differential / drive shaft / setup reconfigured ?

is it possible to swap in the m50b25 wil e30 oil pan ? are they interchangeable between each other aka no modifications what so ever ?

i am going to be stroking the m20b25 to 3.1L and boosting it to 900hp, it would be nice to have a 6 speed

All Wheel Drive is a must.

any other simple bolt up methods, theories, information about keeping the AWD or replacing it with little to no effort is welcome