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Just wanted to pop in really quick and drop this info off. I don't know if I'm just not entering the search terms correctly or if there is a variant that I missed but I was not able to find any information on the correct head bolt thread size for the 3800 V6. I needed this information in order to find the correct thread chasing tap to clean out the cylinder head bolt holes in the block. I know you can also accomplish this by cutting grooves into an old head bolt, but I've always been a firm believer in using the correct tool for the job.
After sending an e-mail to ARP I got a response that the 3800 block uses a 7/16 x 14 thread size for the cylinder head bolt holes. I purchased a thread restorer kit from Sears for 70 bucks that had that size tap in it and it worked.
If you decide to purchase a tap to clean out the bolt holes in the block, do NOT use a regular thread tap. A regular thread tap will remove any metal in its way, and if a thread is out of line, that part of the thread will be removed and compromise the strength of that particular bolt hole.
Again, apologies if this has been posted already but I was unable to locate it through search. If anyone needs the link to the thread restorer kit, I can provide that as well.
After sending an e-mail to ARP I got a response that the 3800 block uses a 7/16 x 14 thread size for the cylinder head bolt holes. I purchased a thread restorer kit from Sears for 70 bucks that had that size tap in it and it worked.
If you decide to purchase a tap to clean out the bolt holes in the block, do NOT use a regular thread tap. A regular thread tap will remove any metal in its way, and if a thread is out of line, that part of the thread will be removed and compromise the strength of that particular bolt hole.
Again, apologies if this has been posted already but I was unable to locate it through search. If anyone needs the link to the thread restorer kit, I can provide that as well.
