Head, and Head Bolt Installation Problem
Thread Starter
Instructor
Joined: Aug 2001
Posts: 167
Likes: 0
From: Dover NH
Done!
I picked up some ARP bolts and related hardware from Summit.
Bolts; $65
Gaskets; $28
ARP Thread Chaser; $32
Lesson's learned and piece of mind; priceless.
I have researched a lot of head bolt threads within this site, and the conclusions were mostly tilted toward getting ARP bolts. The part I missed was "why".
From a layman's perspective, I can tell you that I was impressed with the ARP bolts. Why? First off, I liked the idea of having washers, parallel washers at that. Seems to help spread the load of the head onto a smoother surface than the head itself. Second, the ARP UltraTorque assembly lube that came with the bolts really made it easier to apply the lubricant to the washers and undersides of heads (as opposed to 30 weight oil).
Outside of the bolts, I purchased a really expensive thread chaser. Looked just like my 7/16 14 tap, but I'll assume that since the package said ARP Thread Chaser, that it was indeed a thread chaser. This is a must have if you are going to replace your head bolts. The threads came out real clean.
I "tested" the block threads with a bolt directly into the block with a stack of washers, it torqued right up to 70 ft lbs with no problem. Also, per the suggestion of another member, I also dry fit a bolt and checked for vertical or horizontal play, and found only a minimal amount in the holes that I tested. Block threads looked ok.
The problem was the old bolts and the fel-pro bolts. The original bolts, when measured with a thread gauge, about 6 of them had stretched to some degree. Enough to cause a problem? Guess I'll never know. The fel-pro bolts, let's just say, I'll use their gaskets, but not their bolts.
All the ARP bolts torqued up to 70 ft lbs with no problem, felt nice and tight.
On to the intake manifold...
Thanks everyone, hope someone can learn from this like I did.
Jamie
Bolts; $65
Gaskets; $28
ARP Thread Chaser; $32
Lesson's learned and piece of mind; priceless.
I have researched a lot of head bolt threads within this site, and the conclusions were mostly tilted toward getting ARP bolts. The part I missed was "why".
From a layman's perspective, I can tell you that I was impressed with the ARP bolts. Why? First off, I liked the idea of having washers, parallel washers at that. Seems to help spread the load of the head onto a smoother surface than the head itself. Second, the ARP UltraTorque assembly lube that came with the bolts really made it easier to apply the lubricant to the washers and undersides of heads (as opposed to 30 weight oil).
Outside of the bolts, I purchased a really expensive thread chaser. Looked just like my 7/16 14 tap, but I'll assume that since the package said ARP Thread Chaser, that it was indeed a thread chaser. This is a must have if you are going to replace your head bolts. The threads came out real clean.
I "tested" the block threads with a bolt directly into the block with a stack of washers, it torqued right up to 70 ft lbs with no problem. Also, per the suggestion of another member, I also dry fit a bolt and checked for vertical or horizontal play, and found only a minimal amount in the holes that I tested. Block threads looked ok.
The problem was the old bolts and the fel-pro bolts. The original bolts, when measured with a thread gauge, about 6 of them had stretched to some degree. Enough to cause a problem? Guess I'll never know. The fel-pro bolts, let's just say, I'll use their gaskets, but not their bolts.
All the ARP bolts torqued up to 70 ft lbs with no problem, felt nice and tight.
On to the intake manifold...
Thanks everyone, hope someone can learn from this like I did.
Jamie
Race Director
Joined: Oct 2002
Posts: 12,065
Likes: 2
From: Smalltownville Michigan
Cruise-In 5, 6 & 10 Veteran
St. Jude Donor '09
keep in mind how many explosions those bolts have withstood in their life time. Any time I change heads, I use new bolts. it's cheap insurance.
Safety Car
Joined: Nov 2005
Posts: 3,961
Likes: 573
From: Lompoc, CA. Santa Barbara County
I had a problem somewhat like yours. My block is 33 years old and the heads have been off plenty of times. Also, AFR heads are thicker than stock heads, and with aluminum heads, you have to install thick hardened washers. The stock bolts aren't long enough to grab enough good threads. Go with ARP head bolts or head studs. I did the head studs, but it proved to be a bigger PITA than I expected. I figured the studs would be the best way to go since I changed to some very thin metal shim head gaskets to increase compression.
Bee Jay
Bee Jay
