Engine swapping decisions!

[shrike071]

Well, the S38 I was going to drop in had a cracked head - so I let that one go. Then I was thinking about a 540/6 swap into my 525iT, but that was too intensive. Now I have been pointed to an S50 or S52 swap and I was wondering if there are any pointers out there for pulling this off. I know the engine layout is essentially the same, but my questions are as follows: (and yes, I searched)
1 - If I get the S50/S52 with the wiring and all the electronics, will it be a drop-in replacement? (I will also have a manual trans...)
2 - Any software issues?
3- Will the OBD stuff work with the change?
4 - What about smogging the car?

Your assistance is appreciated!

[winfred]

s50 is a direct swap with all of your brackets, wiring and computer. s52 takes a little more work, use your intake and wiring, brackets and computer, you need to drill and tap a 2nd coolant sensor hole in the head, the boss is there just not poked, you also need to make sure it has the mount for the crank position sensor on the front cover, if not you need to swap timing covers (ain't seen one that didn't have it yet but have herd about it) use your exhaust manifolds on either motor if you don't get aftermarket headers, the us m3 "headers" are not really a upgrade and are not angled to fit the e34 down pipes, plus if you get a obdII motor you will be getting rid of the air injection crap

[penguin]

As above in my 1994 525i. Used everything off the old motor. With the 413 DME you can use a '95 M3 eeprom chip. Added a better clutch but used the M3 (S52 donor car) flywheel and my same transmission. I used the method of using the donor cars temp sensor and made up a custom wire harness for the dual outputs (dash and computer) no drilling and taping then.

Emissions are all fine.

[The Bigfella]

Don't even think about it unless you are doing the suspension and brakes to M3 specs as well. If you are doing the lot - great, it will be balls of fun.

Having both 535 manual (with sports suspension) and M5, I can assure you there is a world of difference in the base car's ability to handle the power when things get interesting - which they do. I've braked hard on a bumpy track from 200 in the M5 and I reckon I would have bent the 535 (big time) from the same speed.

Just my 2 cents worth.

Ian

[RobPatt]

Among E34 535 and M5 we're talking about 100hp difference....

But it's more like 40 (torque too) between the M50 and the S50...not nearly the difference you experienced.

I'd like to consider the same S50+tranny swap... and guessing it'd be fine w/upgraded pads (creamics) and sachs sport suspension w/other parts in good order as well......

No?


Don't even think about it unless you are doing the suspension and brakes to M3 specs as well. If you are doing the lot - great, it will be balls of fun.

Having both 535 manual (with sports suspension) and M5, I can assure you there is a world of difference in the base car's ability to handle the power when things get interesting - which they do. I've braked hard on a bumpy track from 200 in the M5 and I reckon I would have bent the 535 (big time) from the same speed.

Just my 2 cents worth.

Ian