BB exhaust studs

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Uncle Bob

Shiny paint causes stress.
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I'm trying to install Schumacher headers on my Duster w/ a 400 engine, using studs instead of header bolts. I bought a set of studs (2") that matched a couple I found here but they're too long on the head end and won't let the header past to be installed.

The heads are 915s and the studs only went into the heads for about 3/8" before stopping. The shortest studs I've found so far are 1/2" on the head end so those won't thread all the way into the head either. (1-1/2" total Dorman 675-098)

Does anyone has info on stud part numbers that will work?
 
I'm trying to install Schumacher headers on my Duster w/ a 400 engine, using studs instead of header bolts. I bought a set of studs (2") that matched a couple I found here but they're too long on the head end and won't let the header past to be installed.

The heads are 915s and the studs only went into the heads for about 3/8" before stopping. The shortest studs I've found so far are 1/2" on the head end so those won't thread all the way into the head either. (1-1/2" total Dorman 675-098)

Does anyone has info on stud part numbers that will work?
Put the header in place and then screw the studs in.
 
Like you said, may as well use a bolt at that point. I did a quick look and it doesn't appear ARP has any with that short of a head side thread either.
 
Cut the studs down to what you need .

I thought about that, but knowing myself and how tedious that would turn out to be I thought I'd try to buy the right part instead. I'm starting to think I should buy some 1" header bolts and just go with it. I don't think 3/4" bolts will be long enough - the header has a 3/8 flange + the gasket, which leaves few threads to engage in the head. I can stick washers on the outside if 1" bolts turn out to be too long.

It seems odd that the heads won't take more than a 3/8" long stud though.
 
Just run nuts down on the studs ,cut them short and back nut off to clean threads and done deal. Only 12 studs , Fast work with a 3" cut off disk.
 
Local quality hardware store. 3/8-16 setscrews In whatever length you need. (You may have to go to a bolt specialty shop, or order from a place like McMaster Carr.)
Also, I would check the threads in your heads. A 906 head has all the exhaust manifold bolts into water. I don't know for sure with 915s, but I'll bet they are wet too.
There should be a lot more the 3/8 thread depth. I'm guessing you have some serious rust or thread sealer built up.
 
Local quality hardware store. 3/8-16 setscrews In whatever length you need. (You may have to go to a bolt specialty shop, or order from a place like McMaster Carr.)
Also, I would check the threads in your heads. A 906 head has all the exhaust manifold bolts into water. I don't know for sure with 915s, but I'll bet they are wet too.
There should be a lot more the 3/8 thread depth. I'm guessing you have some serious rust or thread sealer built up.
They all seemed to be wet, but after figuring that out I took out the rear bolt first since the front of the car is up in the air and that way I only had one that made a mess.

I was thinking the same thing about the bolt holes, something doesn't seem right but I'm being careful with taps etc because if I screw one up it changes my problem from can't get a stud to work into have to pull the the head(s). The weird part to me if there's something blocking the hole, is that they are all the same. I took them down as tight as I dared and they all stopped at pretty much the same place as witnessed by the thread sealer left on the studs when I took them out. I also ran a thread chaser in, and got the same result.
 
Just run nuts down on the studs ,cut them short and back nut off to clean threads and done deal. Only 12 studs , Fast work with a 3" cut off disk.
Yes, that's exactly the way I'd do it, with nuts double-nutted on the other end and clamped in a vice to keep the studs from turning with the cutting wheel.
 
Sounds like you have checked, cause you're suspicious too.
I have a couple sets of max heads, and both sets have the end bolts on both ends dry, but the rest are wet.
I would run a starting tap (the pointy kind) lightly into a second hole in, till it bottoms lightly, take it out and see if you get rust, or sealer on the tip.
You could also poke a stuff rod in, and see if it stops against something solid, or goes through into a water jacket.
 
Sounds like you have checked, cause you're suspicious too.
I have a couple sets of max heads, and both sets have the end bolts on both ends dry, but the rest are wet.
I would run a starting tap (the pointy kind) lightly into a second hole in, till it bottoms lightly, take it out and see if you get rust, or sealer on the tip.
You could also poke a stuff rod in, and see if it stops against something solid, or goes through into a water jacket.
I'll give that a try and report back.
 
I found out the end holes go on forever and the rest of them are about an inch deep. There was a good coating of crud in there that was stopping me dead. 2 hours with a tap and I've got 7 of them done, 1 has always had a stud in it that I am not taking out so I've got 4 left to do. My back called for a surrender until tomorrow. But the studs I've got will work so at least I've got that going for me.

Thanks for all the advice :thumbsup:
 
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