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Aftermarket manifold [in & out]

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Baz

Baz

Yoda
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Please see pic below.
The Peco header has these knurled nobbly bits where the stud washers want to go. I have a Pierce intake manifold, and there is a 3mm discrepancy between the heights of both manifolds, so the washer won't be flush.
I figure a 1/2 washer on the intake side can get it flush, but have no metal adhesive, welders or anything that can take heat & tightening torque.
Any suggestions... Thanks!

I'm close guys, really close.

e418bda113d45e5eb5ea38bd55cd64610_large.jpg
 
Barry, are the basic flange dimensions close between the intake and the header? If they are, you may get away with grinding those "nobbly bits" down flush with the surface of the mating flange.
I've never seen those bumps on a header before.
Jeff
 
It's important to have the intake & exhaust flanges the same thickness, as you know.

If the exhaust flanges are too thick I would grind/file them to the same as the intake. The "blobs" don't look like a very good seating surface at best.

Maybe they were added to match the thickness of different intake manifold flanges?

You could also add spacers, half washers, to the intake flanges. A bit of gasket glue to hold them in place until things are tightened. No need to permanently attach them. If everything is matched the washers won't go anywhere.
D
 
Re: Aftermarket manifold [in & out]

Persoanlly, I'm really not confident in my handling of the grinder (bench or hand) to be ~that~ precise Jeff.
The exhaust flange is 9mm, the intake is 11mm. With the nobbles, the exhaust is 14mm giving me that 3mm off.
If I were to grind the nobbles, I guess I would be less, and 2mm off in the other direction.
Just being 1/2mm off with this thing would give me a nasty leak.
The old washers from the cylinder head studs are 3mm, I figure that would flush them, just need to stick them.
JB Weld amybe? I've never used it.
 
Re: Aftermarket manifold [in & out]

I think I was replying as you were posting Dave.
No need to permanently attach......Just keep them still enough, until torqued down. I will try that before I reach for the wheel of death, thank you.
 
Re: Aftermarket manifold [in & out]

Barry, I installed a PECO header just a few months ago and it did not have those nobbles, perhaps it could be returned or the supplier could advise you as to whether they belong there or not.
Mike
 
I think they "belong" there: a cheezy way to approximate the thickness of the intake and less production cost for THEM. I've never seen 'em either, but neither have I ever seen a Peco header as a "bolt on" job. they've ALWAYS been a PITA to fit, IMO. Only set of pipes I ever had worth a poop was a Hooker. They quit makin' 'em after the buy-out.
 
Re: Aftermarket manifold [in & out]

I've got a new PECO sitting right next to me & it also has those same dimples....however, I've always made mine fit by modifying the washers themselves.
 
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