Pharmer81

I just put my headers on my 99 FRC and I went to the late model dipstick tube that bolts to the head instead of the manifold. It didn't come with a bolt. What is the bolt size for the head?

nullpointer

I am wondering this too as I need to bolt mine down after XS Power headers. What brand did you install?

lucky131969

My parts manual shows the dipstick tube part number changed for 2001 MY, but the bolt part number is the same from 97-01.

Pharmer81

I also installed XS Power headers.

The bolt from the hold manifolds is a tiny bolt that is far too small. I also tried the bolts from the AIR tube where it connects to the manifold, and they are also too small. I don't want to find out by trial and error with aluminum heads.

lucky131969

Yep. Just passing on the parts manual info I have.

Pharmer81

Sure thing. I appreciate it. I was just updating the post to continue the search, because that bolt doesn't work. Thanks for looking it up for me.

Pharmer81

I called Patrick at GM Parts House. He said it is an M6x1x12 bolt. I'll try to stop by True Value tonight and get a bolt and let you know if it works.

lucky131969

That is the same size as the one you have. Parts manual calls for : M6x1x12.15

Pharmer81

I'll have to look closer tonight then. Maybe I'm trying to screw it into the wrong hole. I know people have done this before, so I assume the head castings didn't change where the new ones have different holes. It's amazing that the most mentally challenging part of the long tube header install is the stupid dipstick hold-down bolt.

lucky131969

Comparison 99 to 04

Pharmer81

I don't know what size it is, but I used one of the bolts from the stock H-pipe to bell housing bracket that I'm no longer using, and it fit perfectly in the head. The head of the bolt is 15mm.