New header and motor mounts ..

yep, another header and mm install.

another :worship: to Brown Dog. what else can i say that hasnt already been said .. other than: all companies should be like that.


the APN header went in with a little angle grinder action to the intake manifold. tubes 1&6 were contacting the intake. fortunately, i read about it before hand and wasnt surprised when it happened.

gasket that came from APN, got upgraded to a felpro from Napa.


one question tho - maybe it's been covered but -

the new APN header flanges are thicker than stock intake manifold flanges. so the surfaces are not aligned and bolts/washers spanning across both manifolds are on an bit of an angle.
I torqued about 5 lbs over spec, in proper order. with the exception of the 2 bottom bolts closest to firewall, couldnt get a torque wrench down there.
anyone having issues with the misalignment?
wise to retorque after a few weeks?

I'd go back over them with your torque wrench after a couple hundred miles just to be safe. Some people suggest replacing those washers- I think they crush a little when installed so sometimes they don't mate right with a new manifold. I forget what they are called, but I'm sure someone like Joe Peters has posted a link on where to find them. Try a search maybe.

If they stay snug and don't allow leaks, I wouldn't worry about it...

Sgtpepper, thank you!

HenryKrinkle said:

I'd go back over them with your torque wrench after a couple hundred miles just to be safe. Some people suggest replacing those washers- I think they crush a little when installed so sometimes they don't mate right with a new manifold. I forget what they are called, but I'm sure someone like Joe Peters has posted a link on where to find them. Try a search maybe.

If they stay snug and don't allow leaks, I wouldn't worry about it...

Click to expand...

The purpose of the dished washers is to take up the tension when the manifold heats up and expands. Flat washers would come loose if there were no locking devide installed. The dished washers allow the manifold to expand and contract without the nuts coming loose.

That makes sense about the washers. Pretty sure they can age/take a set and no longer function.


As for Brown Dog mounts: I can't wait to get a set. My '88 has been begging for them. Will be my next purchase...

Belleville washers, should be replaced for the reasons stated above.

As for the difference in flange thickness, well, most don't seem to be bothered by it. If you want to tweak (which I will probably do), then use some bronze washers to make up the difference.