M30B34 vs. M30B35

[SniperC4007]

My engine blew up and I know someone sitting on an M30 from an 88 535i and wants 600 for it.

here's a chart with all the engine differences
[ame="http://en.wikipedia.org/wiki/BMW_M30"]http://en.wikipedia.org/wiki/BMW_M30[/ame]

But what i need to know is why does the m30b34 have less power and compression than the m30b35? is it just the head gasket or the pistons? and will i need to modify anything before dripping in the new engine?

[GGray]

My engine blew up and I know someone sitting on an M30 from an 88 535i and wants 600 for it.

here's a chart with all the engine differences
http://en.wikipedia.org/wiki/BMW_M30

But what i need to know is why does the m30b34 have less power and compression than the m30b35? is it just the head gasket or the pistons? and will i need to modify anything before dripping in the new engine?

You will loose a ton of power/torque. 18x somethign vs 209 for the motor in your car. I woudl search harder a later motor should not be super hard to find and is much better..

[atl530i]

Normally people swap out the B34 for the B35, not the other way around.

[SniperC4007]

yeah... i figured that. I'll keep looking, thanks for the feedback. Looks like I wont make it to bimmer fest...

[Meeve]

Why does everyone that needs an m30 is so far away from me? Plus I have a 5 speed attached to it. Good luck. If you ever make it to canada buy mine it's in your price range.

[Binjammin]

You cannot use a b34 in an e34. You can use a b35 in an earlier car, but an early engine cannot go in a later chassis. The early engine has a rear sump which will hit the crossmember, and it also has an oil filter canister which won't fit in the engine bay like the upwards pointing canister on the b35.

[Redfive]

It makes less power because it has lower compression, smaller valves and intake and I believe a different cam.

[CO535i]

You can use a B34 in an e34 535i. Two things need to be changed. You will need to use the oil pump, oil pan, from the B35 on the e34. Also you will have to remove the oil filter block off screw from the right side oil port and switch to the top side oil filter. Aside from that it is basically swapping the rest of the B35 specific parts over.

The performance loss has already been mentioned, but if you go turbo the late casting (86, 87, 88) 8:1 compression motor tends to be a better engine for forced induction.

M30B34 vs
Displacement-3.5
Years-85-88
HP/RPM 182 / 5400
TQ/RPM 214 / 4000
Bore 92
Stroke 86
Compression Ratio 8:1

M30B35
Displacement-3.5
Years 88-93
HP/RPM 211 / 5700
TQ/RPM 225 / 4000
Bore 92
Stroke 86
Compression Ratio 9:1

[SniperC4007]

So I scratched the B34 engine idea, although I do want to go turbo, but I rather not mess with all the headaches of swapping out bits and pieces...

So I have a blown piston on cyl 5 with cyl walls all scratched to hell from the connecting rod and a hole on the side of the block, have almost all new everything on the suspension and mounts and did a manual swap so i dont wanna get rid of it that easily. what do you all reccomend i do with getting a new engine? M30, S38 maybe? eh...

[atl530i]

Another M30B35 would work. Freshen up the new M30 and put it in your car.

[TGreene]

Get another M30B35. I know justin517 is selling one for $200. He is in CT and the mileagle is unknown, but he says the compression is good and it runs well.

Other people have engines for sale.

It would not be too hard to find one locally either. M30B35s are very sturdy and common.

[EuroPartConnect]

We have a m30 out of a 89' 535is here at the shop. compression numbers and such were not recorded before we pulled it. 156k on it. But we are only using the head so the bottom end is up for grabs.

[ChiTownTy]

Im buying a new car within the next 2 weeks, my car will be up for parts...I will get around to comp. testing it sometime soon...

[SniperC4007]

well i have my old head with HD rockers, but i dont know of its condition with all the metal fragments...

[Saranrus]

You have the b35 for sale? And what part of Canada?

[zubbie]

ah.... you bumped a thread from 2011.

pretty good bet the engine is gone.

[Binjammin]

Newbs.

[B10 BITURBO]

Normally people swap out the B34 for the B35, not the other way around.

Except in Europe... then you have a high compression M30

[mintus]

Hello All; I have a m30b34 turbo 635 and I have a rusted 635 with a m30b35 engine, so what I have understood is that the head off the b35 may or may not add to my HP addition.


I wish to swap the heads and put my turbo cam in the b35 and hope Bob is your uncle.


I am open for any points of view pro or con if you can be so kind.


Thanks;


Brian