off center stage II. I've ordered bolts TWICE and still can't seem to get the right ones. Both sets I have are ARP #223-3704. the problem is ALL the bolts are 7/16". On my stage II part of the bolts need to be 1/2". What part number do I need? Two weeks and nothing accomplished.
Champion Head StageII head bolts!!??
- Thread starter TurboMike
- Start date
Sounds like somebody pulled some threads out and drilled and re-tapped for 1/2". Check your heads..I wonder if a 1/2" bolt will even fit or if there is enough room to redrill them for 1/2"? Looks like you have an "opportunity for engineering". 
Perhaps you can measure the lengths, call ARP, and see if they can identify 1/2" bolts that will match those lengths for you. Now what torque sequence and numbers would be appropriate, I haven't a clue.
Perhaps you can measure the lengths, call ARP, and see if they can identify 1/2" bolts that will match those lengths for you. Now what torque sequence and numbers would be appropriate, I haven't a clue. FreddieWilliams
New Member
- Joined
- May 26, 2001
My machinist told me he likes to drill & tap the heads bolt threads on Ford blocks to 1/2" to increase torque/clamping force.
Maybe someone was trying to use the same theory on your Buick block.
Just a thought.
Maybe someone was trying to use the same theory on your Buick block.
Just a thought.
Are you looking for bolts or studs? ARP might be able to make you a set of studs with 1/2" threads on one end that then neck down to pass through the head and take stock stud-sized nuts. Also, check the thread pitch in the 1/2" holes to see if it's correct for a helicoil or a normal 1/2" bolt. If it's for a bolt you might be able to use a solid insert but the wall thickness might be too thin. If you can tell me the thread sizes for the holes and for stock bolts (size and pitch, like 1/2-13) I can see what inserts are available.
FYI
Here is what i did. I talked with Tom and Champion and we decided to have a local machine shop open the bolt holes in the heads to 1/2" to allow for the use of a 1/2" bolt. I then contacted ARP to send me bolts to my dimensions. I've got the engine together and sitting in the car. Should be fired up next week. I post how it went.
Here is what i did. I talked with Tom and Champion and we decided to have a local machine shop open the bolt holes in the heads to 1/2" to allow for the use of a 1/2" bolt. I then contacted ARP to send me bolts to my dimensions. I've got the engine together and sitting in the car. Should be fired up next week. I post how it went.
FreddieWilliams
New Member
- Joined
- May 26, 2001
Mike,
Glad you found a solution to your problem.
Does this mean you had to open up bolt holes in the heads to accept the 1/2" bolts?
Let us know how she runs when you get it running.
Glad you found a solution to your problem.
Does this mean you had to open up bolt holes in the heads to accept the 1/2" bolts?
Let us know how she runs when you get it running.
