Page 1 of 1
can your get an iron exhaust manifold planed?
Posted: Mon Mar 10, 2014 10:59 am
by xavier
Can you get an iron exhaust manifold planed to true up the surface that comes in contact with the head?
Re: can your get an iron exhaust manifold planed?
Posted: Mon Mar 10, 2014 11:06 am
by pacerpete
Yes, a pretty straightforward task for a machine shop.
Re: can your get an iron exhaust manifold planed?
Posted: Mon Mar 10, 2014 12:15 pm
by daimlerman
I would not attempt to plane one,I would be asking for the thing to be 'surface ground flat',myself!
Re: can your get an iron exhaust manifold planed?
Posted: Tue Mar 11, 2014 12:46 am
by gareth
No need at all malc, a fly cutter will do the job just fine, as it does on cylinder head faces.
Surface grinding a manifold is overkill of the highest order!

Re: can your get an iron exhaust manifold planed?
Posted: Tue Mar 11, 2014 11:06 am
by xavier
what is the difference between the two?
Re: can your get an iron exhaust manifold planed?
Posted: Tue Mar 11, 2014 3:50 pm
by daimlerman
I have'nt a clue!
My answer is based on dealing with a warped manifold about 20 years ago,when I was running an E28 520i that pulled three studs out.
I'm happy to plane timber,but my plane does not go near metal,it makes an 'orrible mess of the blade.
Re: can your get an iron exhaust manifold planed?
Posted: Tue Mar 11, 2014 7:18 pm
by Brianmoooore
Having a branch of the family heavily into all things CNC, I can answer this one. Fly cutter is a blade similar to that which would be held static against the rotating workpiece in a lathe, but is mounted on a rotating wheel instead. With the workpiece moved against the rotating cutter, it will just cut a circular groove in the surface, but if either the cutting wheel or the workpiece is moved around, the whole surface will be ground flat.
A surface grinder is similar in principle, but substitutes a (usually) cup shaped grinding wheel for the fly cutter.
Re: can your get an iron exhaust manifold planed?
Posted: Tue Mar 11, 2014 8:43 pm
by DanThe
Check out this badboy!
Specially made for an M30 cast manifold?

Re: can your get an iron exhaust manifold planed?
Posted: Thu Mar 13, 2014 4:57 pm
by martauto
xavier wrote:what is the difference between the two?
This is a cnc milling machine and would kill a manifold but with a multi-toothed cutter . The die on the m/c is part of a mould for a "really useful box"
Mart.
Re: can your get an iron exhaust manifold planed?
Posted: Sat Mar 15, 2014 4:12 pm
by capri_rob
yes you can - had mine done by the machine shop who sorted the head test/skim/rebuild out - they said its a bit of a pig to do but its doable.
Re: can your get an iron exhaust manifold planed?
Posted: Sun Mar 16, 2014 11:06 pm
by Dave_M3
Clamping the manifolds is awkward but other than that, it's a very basic task and it's the same as skimming a head or block.
I skimmed the cast exhaust manifold on my TD5 Defender twice as they kept warping and snapping studs. Fitted an aftermarket one then though and had no more issues
Machined an M42 manifold that a friend warped when he got it welded too and was perfect afterwards.
Re: can your get an iron exhaust manifold planed?
Posted: Sun Mar 16, 2014 11:34 pm
by davethegoat
It doesn't help the OP much, but I've used these guys for cylinder heads. A manifold would be a piece of wee I'm sure.
http://www.precision-lapping.co.uk/ Pity manifolds are heavy and expensive to post!