Exhaust manifold bolt question
 

What is the original bolt size, length and style for the factory log manifolds in 1978? Mine are missing and I want to buy something close to correct.

I'm almost sure Ames had bolts when I put the Ram Air pc's of crap on.

3/8"—16 x 2 1/2” per the parts book.

Thanks. Is it a flanged head bolt or just a hex head?

http://i.ebayimg.com/images/g/1iMAAO...QF/s-l1600.jpg

The parts book did not mention different lengths. This kit has 3 different lengths.

http://www.ebay.com/itm/1968-77-Pont...BWQgQF&vxp=mtr

My originals were also some weird hollow bolts. Easier to break off!

true exhaust manifold bolts should be hollow like skip mentioned, or at least all the ones i have seen are. i think that allows for expansion when they heat up. the 3/8-16 thread is correct & im pretty sure they are flanged. not sure if ALL the bolts are the same length though, some manifolds are thicker in some spots so take a longer bolt.

i found the hollow style bolts at my local ACE hardware store. they werent in the big bins with standard bolts they were in teh plastic slide out boxes for specialty itmes.

I will check that out. I looked at the log manifolds and it appears that they will use bolts of all the same length. The Ram Air manifolds appear to have a couple different lengths.

I looked at my local Ace Hardware and they had no bolts that were hollow down the middle. I also contacted Inline Tube and they do not offer a kit for the later engines like mine.

weird, maybe they stopped carrying them due to low sales? i will check my local store to see if they still have them. what size & thread do you need?

3/8" x 16 x ? Not sure of the length I need, maybe 2" - 2 1/2"? I don't have any original bolts to look at, my car came with headers on it.

It appears that the original part numbers are as follows:

9423537-bolt
9779596-washer

I checked with my local dealer and nothing is out there on the locator. The numbers are no longer valid.

Bringing this one back up. Straightening up the shop and went to put the remaining bolts I have and the manifolds back on the original motor on the stand. I have 5 hollow ones left and several solid ones. I do remember pulling them off way back when and several of the hollow ones were seized -why I'm short some. Also a pretty thick washer. The Ames kit has only 8 bolts and the bend over tabs to make a "12 piece" kit but short some bolts if you have manifolds that take 6 each side-and they are solid.

One interesting thing all the holes other than the center two have large holes that a 7/16" bolt could fit in easily. In fact one of the heads on the 220 HP X7 motor I picked up must have stripped out an end one and tapped for a 7/16" bolt.

I have had more trouble with the hollow bolts breaking off than solid. Maybe I will go with stainless steel.

Use antiseize on what ever you use.

any bolt or nut that doesn't require thread sealer or locker i use anti-seize. i hate rusted stuck & broken bolts!

The spray version is good for preserving crank journals in storage too!