M30b34 vs M30b35???

[jonmsm]

Hi all. I am looking into engine swaps (actually for an e28 518i for a friend) and he wants to stick in an M30 motor... however their are two choices, an original e28 motor the M30b34 or one which he has already been offered - an M30b35 sat in a rusty e34....

I am told the e34 engine is still a 3430cc even thou its code would suggests its nearer to 3500cc and that its much more reliable (better sump design amoung other things which i know is useful for an e30 335i conversion) but it appears to have less power (208bhp in the later b35 not 218bhp like in the older b34).

Does anyone know exactly what the differences between the two revisions of the M30 are? and what advantages/disadvantages this gives you, be it for a 335 conversion or otherwise...

Thanks alot - Jon

[snoops]

id go for the b35 as its been done a lot more and so youd have a lot more information/support

[Toby_Unna]

hi jon

the mount holes on an e34 block are wrong for the e28 mount brackets

the engine to car loom plug is completely different

the power difference is due to the e34 engine being rated with cat though many didn't have one. it has bigger inlet valves but the difference isn't big.

in short, much less grief to put an e28 engine in.

or a 750i engine of course

[jonmsm]

Right then - that solves the issue. In fact Toby, I was finding info out for Ben Allen from PPC - but I fear he might have already bought himself an e34 535i... I'll just have to persuade him to stick the engine into an e30 instead and if he still wants a 3.5 for the 518i I'll find a rotten 535 to break cos I am always looking for spares! lol How's the turbo coming btw Toby - I read the latest in PPC and i can see the pic on your post - its looking pretty dam sweet it has to be said! You must come up to Loughborough some - i'd love ooogle it.. and you can see my new car.. its a power monster... a whole 68bhp(and 3 cylinders... its half way there!!) haha