bracken.G8

you have to footpound and then angle torque them which stretches the bolt but for the fasteners is it the same making it where you can reuse them, ik you can reuse head bolts but main fasteners because arp does not make main cap fasteners, im trying to measure my bores for measurements but don’t want to torque these yet to find out i can’t reuse them lol

Che70velle

iTrader: (6)

Yes, you can re-use the main cap bolts. They are TTA fasteners…Torque To Angle. 15 ft lbs both sets of bolts, then go 80 degrees on the inners, and go 50 degrees on the outers. It’s the TTY bolts that can not (or shouldn’t be) re-used…according to GM. Torque To Yield bolts will be your headbolts, and the balancer bolt. Some sites out there list the main bolts, and rod bolts as TTY, but they are not, and are [some what] re-usable. Every fastener has a lifespan, so keep that in mind if your planning on torquing and re-torquing them multiple times. Ive personally torqued the same main fasteners 4 times in several builds, without issue. Pay attention while torquing them, and if you feel one go stretchy on you, stop and back it out. Find another bolt at that point. It’s happened to me once, and only once.

Scotth1977

well we live in America and that entitles anyone to build there motor anyway they choose. You say only once you've had to replace a bolt that stretched to far. Me I took apart my first ls build it is an ls4. Now ive been a full service mechanic my whole adult life i went to trade school in high school and have worked in several dealerships over my 26 year career. I know some dealer procedures can be skirted. I never talk about deviation from dealer procedures unless I did it myself. Now I can tell you I took apart this ls4 with 172k miles. I couldn't do a cam swap while in the car so I pulled the motor. I figured if I pulled the motor it could give me a chance to look at bearings and the rest of the wear on the motor. If you had told me it had close to 200k miles on it I would have said you are a liar. The main bearing looked brand new as well as rod bearings. Cylinder walls still had a faint cross hatch. However the cam bearings had pitting on the end bearings. When I pulled the crank I decided to do an experiment to see if I could get the same clearance specs with the old main cap bolts. I put a piece of plasti-gauge on each journal and proceeded to tighten the bolts to spec. Only 3 of the bolts were able to hold the 80 degree turn the rest just started to stretch. These were the factory bolts that came with motor when it was born. I knew the previous owner who bought the car new. He never had the motor out. I definitely will be buying arp studs and arp rod bolts. I don't feel right if I can't check and know the bearing clearances when I freshen up a motor. Sometimes that involves tightening and loosening the bolts multiple times and you can't do that with a TTY or TTA bolt. That's why arp is my go to for engine fasteners they just are a little expensive. Plus when I throw a turbo on the motor later the bottom end is already beefed up with larger ring gaps. This is in no way shape or form instructions its just my experience. I won't re use tty bolts.

SlowTBSS

Just make sure you have the block and rods machined, the new fasteners can/will distort things and bring them out of round.

Scotth1977

I understand that why I plan on using plastic-gauge to double check oil clearance on the mains. However there is nothing I can do about about the rods since they are cracked rods and can’t be resized. I checked 2 of the rods before I sent the crank out to be polished and ended up with.0015 on both I’m pretty sure that is in the ballpark. The machine shop ive been using for years can’t do a line bore on an ls motor. He says he doesn’t have that many coming in so can’t justify buying the accessories to do one motor I don’t really know what piece of equipment he would have to buy I know he can do it on conventional motor like Chevy ford Chrysler etc

G Atsma

One thing- Plastigage is NOT an accurate way to check clearances. Ask anyone else here...