Exhaust Manifold

#1

I’ve been searching for a while now to figure out whether the ‘e’ and ‘i’ manifolds are the same and haven’t come up with an answer. I was hoping to just clean the ones off my ‘es’ and slap them on the new engine I put together. I don’t think they are any different from all the ones I’ve seen, but if anyone knows for sure I’d appreciate the help.

Thanks,
Armando

#2

aperez wrote:

[quote]I’ve been searching for a while now to figure out whether the ‘e’ and ‘i’ manifolds are the same and haven’t come up with an answer. I was hoping to just clean the ones off my ‘es’ and slap them on the new engine I put together. I don’t think they are any different from all the ones I’ve seen, but if anyone knows for sure I’d appreciate the help.

Thanks,
Armando[/quote]Part numbers are not the same:
http://www.realoem.com/bmw/

I have a set from an 87 and from an 89

#3

Yeah, I checked the ETK and saw they had different numbers. I guess the question should have been more of, does anyone know what the differences are. I’ll have to take a look around the shop and try to find some specific to the i I guess. Thanks for the help!

#4

After some more searching on the ETK, I found that all the 325’s use the same exact gaskets on both sides of the manifold,regardless of which manifold. So I think it’s safe to assume the ports are all the same size. Perhaps the downtubes are different which require the manifolds to be different for mounting purposes. Sean, if you don’t mind taking a look what differences if any can you see on the 87 vs. the 89?

#5

Per the Spec E30 rules, I think the only safe solution is to use the exhaust manifold from an M20B25.

#6

Granted, I’ve already grabbed some ‘i’ manifolds so it’s not a rules question anymore really. Now it’s just become a curiosity thing. On the newest ETK it actually shows the same part number for e’s and i’s (haven’t checked every year combo, but when you search by the part number it can show you other uses for the part and it shows both e’s and i’s) so now it’s really making me think what the differences were and why the numbers used to be different. Either way, the i manifolds are cleaned up and ready to go on the engine which I just dropped into the car last night.