bmwe21.net forums

Hi All.

Will an original E30 exhaust manifold will fit th E21? 316 M10.

Im mid way through head change to the 1.8i. Have ported the head which is now ready for fitment. (pics later in the week).

Ive dropped my manifold off the old head and the ports are about 30mm circle shaped. Will the E30 manifold be larger/oval and will it fit?

Any ideas? i cant afford a tubular manifold at the minute, but want my new head not to be massively restricted.

Thanks
Rob

Hi Rob,

No from experience.

Not sure if you've seen my post

http://www.bmwe21.net/forum/viewtopic.p ... 3&start=30

Angle is all wrong and no ammount of jigging will help.

Thanks,
Just had a quick look over your thread, 323? im talking 316.

Have you had experience trying it on the M10?.

Ah true,

I'll have to leave someone more informed to answer that one!

I can't imagine why the e30 M10 manifold would be mCan you post up some pics of one. The problem with the 6 pots seems to be the back manifold fouling the steering knuckle, but with our lovely little 4 pot motors you tend to have downpipe there rather than lots of manifold.

You could always do a bit of port matching on your original manifold if the e30 one won't fit.

Tubular ones look nice but I dyno'd my old 316 before and after fritz bits manifold fitted - no difference.

tbh with the fritz manifold it'll be restricted by all the doggy long bits of mig wire hanging about inside lol.

only joking. but im surprised there was no difference!

i was planning on porting the original manifold to match, or at least get somewhere near my new 1.8i exhaust ports...but there's just not enough material in it.

As the 1.8i head ex ports are larger and more oval i was thinking, surely a later manifold would be a little larger.
Id still be expecting to do a little tinkering with the tools, but just want something witha a bit more material, or with a more oval shape.

Think ill visit a breakers tommorow with my existing manifold and just have a rummage, line them up, and see how i get on.

Cheers.

The dyno figures were not significantly different, maybe a couple of bhp, but it was a year later, different oil, maybe standard unleaded not optimax, different air temp etc. Different dyno as well - he'd upgraded. The engine may have been a bit better, but the torque/power curves were the same shape.

The power of an M10 soon blasts the bits of MIG wire out anyway.

sounds like you need a exhaust manifold from a early 4 cylinder 320/320i e21 as the ports are larger and match the larger e30 318i ports

Thank you Mr Edd.

I will check the local breakers tommorow.
Failing that ill soon be posting said manifold in the wanted section.

An hour with the welder and a die grinder and i now have oval matched ports on my manifold. )
Should be running by tommorow lunch.