71 lemans header bolt problem.

SPCMarty · 02-25-2013, 03:40 PM

It's practically ridiculous that I'm asking for help on a measly bolt. I have 4 tube headers on my 400 and I cannot for the life of me figure out an angle to tighten the second bolt from the rear of the engine on the passenger side. The tube blocking my attempts; belong to the #6 cylinder.

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rickm · 02-25-2013, 04:26 PM

its not ridiculous, some header designs and hardeware are ridiculous. dont know what type of header bolt your dealing with. i have an array of small combonation wrenches with thin walls and even some i grinded down specifically for headers. ive seen some guys use an allen type header bolt for the difficult ones. can you get it from underneath with a 1/4" ratchet , extention, universal? you should always start your sequence from center port out.

SPCMarty · 03-12-2013, 04:52 PM

It's just a typical 9/16 bolt. I tried posting pics but it didn't seem to work.

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joesweeting · 03-12-2013, 05:33 PM

I had hooker headers, I had to use two combination wrenches and a rubber band. Used the open end on the bolt and connected the box end of that wrench to the open end of the other. Used the rubber band to keep the open end from sliding off the box end. It was a pain, I now have oversized Ram Air exhaust.

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ALKYGTO · 03-12-2013, 05:59 PM

So your not using "header" bolts with the small heads?

If your not it's a wonder you only have a problem with one of them. Also I would'nt run "soft" hardware store bolts on the exhaust headers. Do the right thing and buy some ARP or Mr. Gasket header bolts.

You can thank me later.

SPCMarty · 03-12-2013, 06:21 PM

No I'm not, grade 8 bolt from menards. Used those for every bolt, just this one giving me trouble.

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Pontibeast · 04-11-2013, 02:41 AM

I had the same problem with a set of Hooker super comp headers in my 71 Lemans but it was on the drivers side. I had to grind down the open end of my wrench and order a set of header bolts because they give you more room to work. They also make some with an allen head in the center that are supposed to work very well and you don't have to tighten them again after you drive the car for a couple of hundred miles to allow for heat and cooling cycles. I ended up getting the best access from underneath standing under the tranny facing the front of the car if that helps any. Good luck to you.

Rukee · 04-11-2013, 07:42 AM

with Alky, go to an auto parts store and grab some header bolts. They have a small head, fit better and won't stretch like the reg bolts.

69Goatee · 04-17-2013, 12:28 PM

I bought a set of Stage 8 locking header bolts made for BBC (longer shaft than Pontiac). On the same bolt you are having trouble with I got a couple of parts store 7/16 head header bolts, ground the top corners of the hex round for more clearance and drilled two 1/8" holes across two of the flats. Then I used an 1/8" allen wrench or drill bit to tighten the bolt. After they were tight I put a cotter pin in one of the holes and bent it so it just touched the header pipe and will not come lose.