• Spring 2024 meetup in Calgary - tentative date Saturday, April 20/2024. Other regions are also discussing meet ups. If you want one in your area get going on organizing it! discussion
  • We are having email/registration problems again. Diagnosis is underway. New users sorry if you are having trouble getting registered. We are exploring different options to get registered. Contact the forum via another member or on facebook if you're stuck. Update -> we think it is fixed. Let us know if not.
  • Spring meet up in Ontario, April 6/2024. NEW LOCATION See Post #31 Discussion NEW LOCATION

YYC - Resurface turbo exhaust manifold

Hi seeking if anyone local here can help me and keep it within the hobbyist community
if there's anyone in Calgary or even in the Calgary NE area who can help that would be great!

I have seen some youtube of people using a large belt-type sander or milling machine.

IMG_2357[1].JPG IMG_2359[1].JPG IMG_2358[1].JPG
 
Last edited:

Everett

Super User
I have milled a number of manifolds, but before I had a mill I replaced the exhaust manifold gasket on my 2003 Dodge 2500 Hemi I used to own. I used my belt sander and some fairly rough belts (60 to 80 grit or so) and checked against a straightedge as I went. So yes, a belt sander does work to get the warpage out too. From your measurements it sounds like your manifold shouldn't need too much working compared to the 5.7 Hemi manifolds. I did a pair of them a week and a half ago and one needed .060" milled to straighten it, the other .050" off.
 

Janger

(John)
Administrator
Vendor
I have milled a number of manifolds, but before I had a mill I replaced the exhaust manifold gasket on my 2003 Dodge 2500 Hemi I used to own. I used my belt sander and some fairly rough belts (60 to 80 grit or so) and checked against a straightedge as I went. So yes, a belt sander does work to get the warpage out too. From your measurements it sounds like your manifold shouldn't need too much working compared to the 5.7 Hemi manifolds. I did a pair of them a week and a half ago and one needed .060" milled to straighten it, the other .050" off.
Everett did your exhaust manifold on the hemi have multiple flanges similar to digitalbilly? is it critical that all the flanges are on the exact same plane or will the gasket even it out?
 

phaxtris

(Ryan)
Premium Member
Premium Member
Most engine shops can resurface that manifold for you, pretty standard item. I can't help, my mill isn't big enough :(

Looks like a Cummins manifold ?
 

Everett

Super User
@Janger - the Chrysler 5.7 Hemi manifolds each have 4 individual flanges, nothing Siamesed like an old school Chev 350 manifold. I found from experience that once you get them all into about the same plane they are fine from then on. The outer ones warp away from the heads, breaking the bolts off, and giving the "Hemi exhaust tick."

The manifolds from new are fresh castings that just get machined and put on an engine. They don't "season" them, the metal casting stresses come out over time with heat/cool cycles. And, for what it's worth, they will still seal for a bit even with just replacing the gaskets and slapping them back on, the only issue is that over time they will pop the manifold bolts off yet again. Anyone who has had a manifold gasket done on warranty will have a 95% chance the original, warped, manifold will have been reinstalled, as-is. And the same problem will happen again, but the warranty clerk and service manager generally don't care. If you even just use a belt sander to take the cold manifold flanges to pretty much the same plane you won't have the bolt-breaking problem again. We're not talking AA surface plate flatness here, even using the side of a yard stick will be good enough. Exhaust gaskets give a little bit of wiggle room.

In looking at the picture, I would have to agree with @phaxtris if I had to make a guess - 8.3 Cummins? Reason I am guessing that too is that I've done an 8.3 manifold as well, a couple years ago, for a grain truck that came in the truck shop.
 
Well you could get a granite drop probably cheap from a counter installer. You know there was one down the alley it was 5’ long. I’ll go see if it’s still there.
EDIT -> Nope it's gone.
Arg gone! thanks for checking.

I guess the best bet would be to see if I can find a piece free or cheap next to nothing.
 

PeterT

Ultra Member
Premium Member
Kijiji might have some prospects that meet your length requirements. The trick is how flat is flat for your requirements. Some of the granite shops might have skinny offcuts useless for them but perfect for you. Or be able cut a slab you acquired elsewhere. Countertop granite is polished on the glossy side vs ground matte like a surface plate, so it may not take on 'blue' if you were looking to transfer where the high (contact) areas were. But maybe there are other workarounds.

I've shimmed recycled glass bookshelves to be sufficiently accurate for other applications & they come in convenient aspect ratios for your need, but maybe not as forgiving a surface.
 

Attachments

  • SNAG-2022-10-04 6.00.07 PM.jpg
    SNAG-2022-10-04 6.00.07 PM.jpg
    60.7 KB · Views: 20
  • SNAG-2022-10-04 6.00.44 PM.jpg
    SNAG-2022-10-04 6.00.44 PM.jpg
    128 KB · Views: 21
Look a sheet of 3/4" MDF on a floor can work just as well. Lay a belt of sandpaper on it and go at it. Remember you are trying to clean it up and get it within a couple of thou...

There are a couple of YouTube videos out there of guys doing ghetto cylinder heads that way.

Remember the perfect tools make it easier, but a good machinist can do it with the any tools at hand and get the required results.

Think out side the box, even better use the box.
 
Last edited:

Chicken lights

Forum Pony Express Driver
@Janger - the Chrysler 5.7 Hemi manifolds each have 4 individual flanges, nothing Siamesed like an old school Chev 350 manifold. I found from experience that once you get them all into about the same plane they are fine from then on. The outer ones warp away from the heads, breaking the bolts off, and giving the "Hemi exhaust tick."

The manifolds from new are fresh castings that just get machined and put on an engine. They don't "season" them, the metal casting stresses come out over time with heat/cool cycles. And, for what it's worth, they will still seal for a bit even with just replacing the gaskets and slapping them back on, the only issue is that over time they will pop the manifold bolts off yet again. Anyone who has had a manifold gasket done on warranty will have a 95% chance the original, warped, manifold will have been reinstalled, as-is. And the same problem will happen again, but the warranty clerk and service manager generally don't care. If you even just use a belt sander to take the cold manifold flanges to pretty much the same plane you won't have the bolt-breaking problem again. We're not talking AA surface plate flatness here, even using the side of a yard stick will be good enough. Exhaust gaskets give a little bit of wiggle room.

In looking at the picture, I would have to agree with @phaxtris if I had to make a guess - 8.3 Cummins? Reason I am guessing that too is that I've done an 8.3 manifold as well, a couple years ago, for a grain truck that came in the truck shop.
On my first big truck the exhaust manifold was 2 or 3 pieces (don’t remember) with Cummins probably trying to build in a joint to allow some flex. Don’t ask me why but I had to buy a new short end piece (again, don’t remember the reason), they sent it out to get machined because of the number of mating surfaces that needed to line up. They machined a few reference points and clamping points, before committing to doing the flanges.

Way above my pay grade but it turned out nice
 
Look a sheet of 3/4" MDF on a floor can work just as well. Lay a belt of sandpaper on it and go at it. Remember you are trying to clean it up and get it within a couple of thou...

There are a couple of YouTube videos out there of guys doing ghetto cylinder heads that way.

Remember the perfect tools make it easier, but a good machinist can do it with the any tools at hand and get the required results.

Think out side the box, even better use the box.
Ok sounds good think “outside the box”. Me being super newb here what sand paper grits should I start and finish with? I have feeler gauges and a precision strait edge for checking Cylinder heads and engine blocks. Basically follow this technique Resurface
 
Last edited:
Kijiji might have some prospects that meet your length requirements. The trick is how flat is flat for your requirements. Some of the granite shops might have skinny offcuts useless for them but perfect for you. Or be able cut a slab you acquired elsewhere. Countertop granite is polished on the glossy side vs ground matte like a surface plate, so it may not take on 'blue' if you were looking to transfer where the high (contact) areas were. But maybe there are other workarounds.

I've shimmed recycled glass bookshelves to be sufficiently accurate for other applications & they come in convenient aspect ratios for your need, but maybe not as forgiving a surface.
Perfect thanks.
 
Top