Intake manifold help

[whit68]

G’day everyone,

I am swapping my old 318 manifold over for a new Edelbrock Performer.

When I try and fit the new manifold the bolt holes on the manifold don’t line up with the ones on the heads (about a third of the hole out). I am guessing I need to machine the new manifold but how do I know how much needs to come off?

Cheers
Anthony

 

[krazykuda]

G’day everyone,

I am swapping my old 318 manifold over for a new Edelbrock Performer.

When I try and fit the new manifold the bolt holes on the manifold don’t line up with the ones on the heads (about a third of the hole out). I am guessing I need to machine the new manifold but how do I know how much needs to come off?

Cheers
Anthony

View attachment 1715204924

Are you using the roll pins on the end gaskets for the intake manifold???

If you do have them, make sure that there are clearance holes in the intake for them or they may prevent the intake from going down far enough....

 

[whit68]

Quick reply Krazykuda! The roll pins have been removed so unfortunately it is not that.

Cheers
Anthony

Are you using the roll pins on the end gaskets for the intake manifold???

If you do have them, make sure that there are clearance holes in the intake for them or they may prevent the intake from going down far enough....

 

[rumblefish360]

Remove any roll pins on the china walls so the intake sits flush.
Then try pushing down on the intake a bit and see if things line up any better. If you get close and you still have the gaskets at the ends of the intake to block, remove those as well and use gasket adhesive in the gaskets place.
If you can not squeeze the intake on, talk to a machinist with pictures galore in hand.

Most machinists want everything there to work on and often shy away from guess machine work on something like this.

Try and get a better picture showing the misalignment directly overhead. Showing the walls of the intakes hole all around. Get all the hole pictures if you can but for certain, the 4 outter most on each corner.

 

[krazykuda]

Quick reply Krazykuda! The roll pins have been removed so unfortunately it is not that.

Cheers
Anthony

Then measure the intake bolt center line on the intake and then on the heads... Make your marks on the centers of the bolt holes on the intake and heads as the end bolts are slightly lower...

Then measure the bolt center line for the intake and then the heads on the engine and see which one is bigger...

 

[RustyRatRod]

Remove the gaskets and see how close that gets you. If that allows the holes to line up. mic the gaskets and have the intake machined that much.

 

[yellow rose]

Take the gasket off and measure it. If it's .045 thick, you need to take that much off. If there is no gasket in that picture you need the gasket thickness plus about .040 more.

 

[yellow rose]

Remove the gaskets and see how close that gets you. If that allows the holes to line up. mic the gaskets and have the intake machined that much.

RRR treed my arse. Again.

 

[whit68]

Thank you gentlemen for your replies. I have no gaskets fitted in the picture so I’ll have to measure the centres and go from there.

...or could the machine shop use the original manifold for reference?

Cheers
Anthony

 

[yellow rose]

Thank you gentlemen for your replies. I have no gaskets fitted in the picture so I’ll have to measure the centres and go from there.

...or could the machine shop use the original manifold for reference?

Cheers
Anthony

If the manifold is in the correct spot in the picture you posted, you are about 1/3 of a hole off. That's what it looks like in the picture. With no gasket in there, you need to remove whatever the thickness of the gasket is you are going to use, plus another .030-.040 to make up for not being line up now.

In other words, if you put the manifold on with no gaskets and the holes lined up perfect, you only remove the thickness of the gasket. The intake is too wide without the gasket, so you need to remove the thickness of the gasket plus another .030-.040 to get it the correct width.

And that means you are taking the gasket thickness plus the extra amount off each side of the intake manifold. This happens all the time. Not abnormal at all. Some guys want to take it off the intake face of the head but I almost never do that.

 

[whit68]

Thank you sir. I’ll go with .030 + the gasket thickness and see how I go. Appreciate your help.

Cheers
Anthony

If the manifold is in the correct spot in the picture you posted, you are about 1/3 of a hole off. That's what it looks like in the picture. With no gasket in there, you need to remove whatever the thickness of the gasket is you are going to use, plus another .030-.040 to make up for not being line up now.

In other words, if you put the manifold on with no gaskets and the holes lined up perfect, you only remove the thickness of the gasket. The intake is too wide without the gasket, so you need to remove the thickness of the gasket plus another .030-.040 to get it the correct width.

And that means you are taking the gasket thickness plus the extra amount off each side of the intake manifold. This happens all the time. Not abnormal at all. Some guys want to take it off the intake face of the head but I almost never do that.

 

[RustyRatRod]

I bet that gets it spot on or real close. Good luck.

 

[whit68]

Thanks for you help with this one folks, just thought I’d close the loop.

I ended up with 40 thou plus the gasket thickness (and a skim off the base of the manifold) and it all fits perfectly. I’ve had it out on the weekend for a 200km run with no issues at all - well except for a pinhole leak that I had taken to a radiator shop specifically to be fixed .

Cheers
Anthony

G’day everyone,

I am swapping my old 318 manifold over for a new Edelbrock Performer.

When I try and fit the new manifold the bolt holes on the manifold don’t line up with the ones on the heads (about a third of the hole out). I am guessing I need to machine the new manifold but how do I know how much needs to come off?

Cheers
Anthony

View attachment 1715204924