Main studs and rod bolts
Main studs and rod bolts I am about to install TSP race heads and magic stick cam. I may also be spraying in the future. Do I need main studs and rod bolts and how hard are they to install. Thanks
I would definately do rod bolts. I am not sure main studs are necessary. I am rebuilding my motor now (spun rod bearing), and decided to put main and head studs in, along with ARP rod bolts (wish I had done these sooner).
Staging Lane
Joined: Apr 2004
Posts: 68
Likes: 0
From: Houston, TX
You don't have to do main studs. Everyone says the weak link in the LS1 bottom end is the rod bolts. They can be done with a lift while the engine is in the car. You must take precautions to make certain that the same rod bottom is bolted to the rod it came from and in the same direction.
Technicaly, I would only do this if the engine was going to be pulled and all clearances properly checked. The rods should be checked with the fasteners that will be used. This is also true for the mains. New fastners should require that the block be aligned honed with torque plates again for the main journals and the rods should be checked for roundness and bearing clearances. Fastners put their own unique stress on the block and rods and this can change the clearances and geometry of the rotating assembly causing premature failure which is what you are trying to avoid in the first place.
Technicaly, I would only do this if the engine was going to be pulled and all clearances properly checked. The rods should be checked with the fasteners that will be used. This is also true for the mains. New fastners should require that the block be aligned honed with torque plates again for the main journals and the rods should be checked for roundness and bearing clearances. Fastners put their own unique stress on the block and rods and this can change the clearances and geometry of the rotating assembly causing premature failure which is what you are trying to avoid in the first place.
Joined: Nov 2001
Posts: 3,043
Likes: 0
From: Texas and Qatar
The rod bolts are a good idea if you can get to them. With the cracked-LS1 style connecting rods, I've put many ARP bolts in without checking for roundness. Remember each cap will only fit its matching rod as the fracture line will only allow the matching fracture to bolt up properly. You can throw all 8 rod caps in a bucket and find the matching rods just by lining up the fracture marks, thats how unique they are. It would probably work for 100 different rods in the same fashion, although I've never tried that many! 
On one stock shortblock that had ~3000 miles with ARP rod bolds we took it apart (for stroker) and the rod bearings look exactly the same as when the bolts were installed with no wear pattern at all, so I doubt there is any excessive stress caused by a better bolt being installed and pulling the big end out-of-round. Someday I'll verify that with a dial bore guage, although if its tweaked enough there is very little that can be done to fix it other than throw the rods away. Its recommended to do an align hone when doing main studs, but I've never seen an engine fail from stock main studs, I only install them in the customers engines that specify they want them.
On one stock shortblock that had ~3000 miles with ARP rod bolds we took it apart (for stroker) and the rod bearings look exactly the same as when the bolts were installed with no wear pattern at all, so I doubt there is any excessive stress caused by a better bolt being installed and pulling the big end out-of-round. Someday I'll verify that with a dial bore guage, although if its tweaked enough there is very little that can be done to fix it other than throw the rods away. Its recommended to do an align hone when doing main studs, but I've never seen an engine fail from stock main studs, I only install them in the customers engines that specify they want them.
