M30b35 swap compatibility

[Beanman69]

Hello

I have been perusing the M30b35 swap FAQ page for a long time and I am finding a couple pieces of information that are either not quite well presented or does not have information available.
I am currently swapping a 91 m30b35 into my 77 530I after my transmission and engine have both mysteriously died. I have already rebuilt the M30b35 along with adding a turbo for some extra power and sourcing a G265 transmission to pair it with.
one foremost question and concern. now that I am about to swap it and I am pulling the engine bay apart, is brake booster clearance a concern? Has anyone had any fitment concerns with the stock brake booster, and if so, how did you resolve it?

I’m really hoping I don’t need to get a different booster but if it turns out I need to, so be it.

Thanks so much!
-Justin

[Mike W.]

I have not done it, but back when B34 swaps were in vogue I recall using an E21 booster was popular as it gave the required clearance. B34 and B35 intakes are very similar in shape, but I don't know if they are identical or not, aside from the intake port shape. But search a bit, like I said I have not done it myself.

[Theotherotter]

Hello

I have been perusing the M30b35 swap FAQ page for a long time and I am finding a couple pieces of information that are either not quite well presented or does not have information available.
I am currently swapping a 91 m30b35 into my 77 530I after my transmission and engine have both mysteriously died. I have already rebuilt the M30b35 along with adding a turbo for some extra power and sourcing a G265 transmission to pair it with.
one foremost question and concern. now that I am about to swap it and I am pulling the engine bay apart, is brake booster clearance a concern? Has anyone had any fitment concerns with the stock brake booster, and if so, how did you resolve it?

I’m really hoping I don’t need to get a different booster but if it turns out I need to, so be it.

Thanks so much!
-Justin

I have a '78 with a B35/G265 swap in it. Late last year I found the forum ID of the prior owner who did the swap and a bunch of other work on it and a bunch of posts that filled in my knowledge of the car's background. In one of them, he said "One more thing that I mentioned - make sure you have the shorter brake booster. The longer one will interfere with the intake manifold." I'm assuming he meant the E21 booster.