Exhaust manifold machining
Turbo Mini Forums

im finding it hard to get my ex manifold face machined flat, the firm i usually use say they cant grip it.

anyone had this problem?

"Turbo's make torque, and torque makes fun"

"did you know you can toast potato waffles?"

I got mine done no probs. If you really struggle i could probably get it done for you.

WWW.TURBO-MINI.COM

cheers phil, i might have to take you up on that offer, gonna try the plant hire place near me first though.

"Turbo's make torque, and torque makes fun"

"did you know you can toast potato waffles?"

Shit !
Just a thought, are you talking about the Turbo flange/face ? or the branches/runner to head face ?
If it's the Turbo face, i got this done no probs. Though they said the manifold to head face could possibly be a struggle, so i hand filed these.

WWW.TURBO-MINI.COM

If we're talking about the manifold / head face; All I did was get a piece of 1" box section to use as a straight edge.

I then carefully ground material off the faces on the outer runners, checking flatness all the time.

You can actually go pretty hard initially, as they usually need skimming a LONG way before they're right.

As you get closer to level, be a little more careful.

To finish off, I used a BIG bastard file - big enough to touch the centre flange and stroke one of the outer flanges.
The idea, is you use the centre as tyhe datum to keep the file true, and basically only remove the material off the outer branch.

A little grease on the centre flange will asist in minimising any damage.

Keep using the striaght edge to check for true whist removing material.



From my experience, the manifold will need 'doing' twice if it has more than a 3mm or so gap at the centre flange before starting; with this in mind, don't go overboard in getting it perfectly flat. If you are within 1mm or so offset on the centre, it'll pull up just fine...

Next time you take it off chances are you'll have to tickle it all again!

I also chamfer the edges of the flanges, such that the manifold is pulling hard against the metal firing ring on the gasket, rather than the gasket material itself. I'm not talking a huge chamfer, but it is apparant.

All the above will take no more than 1hr or so - providing you have a good bench vise, grinder and file.

yeah the manifold/head face

right, im off down the garage then

cheers

"Turbo's make torque, and torque makes fun"

"did you know you can toast potato waffles?"

File can take hours !!!!

Ive tried to get a local machine shop to make flat a manifold I made ages ago for my old Granada.
Eventually they did it, not very well, and charged a fortune for the pleasure.

Its weird, that I can give it to a friend who also works in a machine shop, and he says its easy.
He now does most of my work....

Good machinists are hard to find.

9.85 @ 145mph
202mph standing mile
speed didn't kill me, but taxation probably will

Lucky me. My machinist has got this thingy to mount manifold on a planing thing. It's not a mill, but a stone wheel. What's it called?

flat bed grinder?

a big grinding stone/wheel ? lol

9.85 @ 145mph
202mph standing mile
speed didn't kill me, but taxation probably will