slowjoe99

iTrader: (7)

Here is what my crank looks like...


So i'm obviously getting a new crank and rod. My question is, is it safe to use the stock main cap bolts again after installing the new rotating assembly, or are the stock bolts stretch to yeild?

Black01M6SS

iTrader: (3)

They are torque to yield so you will need new ones or ARP studs.

Halloran

iTrader: (7)

Replacing the main cap bolts and studs is not required per the GM service manual. The bottom end of these stock motors are good up to a debatable 1,000 horses. However, if you are planning on going with a stroker and a larger cam then I would highly recommend upgrading to some ARPs. I'm sure there are plenty of people including myself that have reused the main cap bolts and studs and haven't had a bit of trouble. Just my $.02.

ItsNotStock

iTrader: (24)

These bolts are not re-usable. They are stretch fit bolts as Black01M6SS stated. For the money you are going to be spending on getting new bolts ARP studs for a little bit more are well worth it.

And 1,000 hp? That's laughably debatable. I hope you meant the crank, and not the "entire" bottom end. If the stock rods, and pistons could handle 1,000 hp you would see alot less people buying rotating assemblys from companies like Texas Speed. I have personally seen the pistons fail in a LQ4 engine with a single Garrett 88 turbo pushing no more than 6 pounds of boost with impeccable tuning. I would trust the crank, but throw anything else away pushing close to 500whp or more let alone 1000....

Halloran

iTrader: (7)

Yes thanks for the correction. By 1,000 horses I mean that's the limit of the crank not for the entire bottom end lol! I would also like to know what the definitive answer is on the reuse of main cap bolts. Some say yes and some say no. Is there really a definitive answer...has anyone done any real research into engine failure due to faulty stretch on main bolts? Here are just a few links I found on the reuse of main bolts.

https://ls1tech.com/forums/showthrea...lts+reuse+main

https://ls1tech.com/forums/showthrea...lts+reuse+main

https://ls1tech.com/forums/showthrea...lts+reuse+main

https://ls1tech.com/forums/showthrea...lts+reuse+main

https://ls1tech.com/forums/showthrea...lts+reuse+main

https://ls1tech.com/forums/showthrea...lts+reuse+main

Black01M6SS

iTrader: (3)

I doubt anything bad would happen if you reused them but that doesn't mean I would do it or recommend that anyone do it. I was tought that torque to yield bolts get replaced. You could probably get away with building it without a torque wrench or a torque angle gauge but that doesn't mean I would try that either.

Edit: It seems some people believe that they are not torque to yield. I assume they are since they have a torque angle spec instead of a normal torque spec. I could be wrong but I've always been told that anything with a torque angle spec is a torque to yield bolt and is not ment to be reused. With all the controversy about this I would just replace them to be sure.

Randy WS6

iTrader: (69)

yes ,you can reuse the main bolts, Just not the head bolts or crank bolt ,they are torque to yield.

NavyBlue99SS

Dont be cheap thats how you run into trouble and learn lessons. Look at it this way. Your already in there and your questioning if you should or not correct? Go ahead and replace them with good bolts or studs. Dont mess around or you could get burned.

AFASTYZFR1

iTrader: (55)

I agree....just replace them to be safe

NEGEN@SDPC

iTrader: (9)

Hey guys and gals just wanted to help clear this up all these bolts listed are going to be a torque to yield bolt. All GM head bolts, balancer bolt, and all the GM mains except the ones that will go through the side of the block....Thanks..

slowjoe99

iTrader: (7)

i am going to use NEW stock bolts. i only needed 20 of them. got them at the dealership for 85 bucks...

Black01M6SS

iTrader: (3)

Good choice

1_bad_TA

iTrader: (6)

If you have it that far apart, why cheap out. Get a set of ARP's.

Randy WS6

iTrader: (69)

You can get Fel-Pro stock head bolts at Advance Auto for 50.00 for both heads. Just trying to help. But if your planning to remove the heads in the future you need to go with ARP because you can reuse them over and over. ARP bolts will be the last set of head bolts youll ever buy.

9secondsflat

sure you can resuse the bolts, its just like using a condom twice...but do you really want to???

Black01M6SS

iTrader: (3)

Good one lol

bluecajun5.3

iTrader: (31)

well that sucks.
it looks like the only way to check clearances with plastigauge is to buy apr studs.

ss.slp.ls1

iTrader: (36)

I thought you use them till they break...

When my heads or any other components come off, ARP's are definitely going in.

2002_z28_m6

iTrader: (10)

For the money you have invested its not worth chancing it. Buy some arp's and know its done right. just my .02

KCS

iTrader: (20)

You CAN re use TTY bolts.

Torque To Yield bolts do exactly what they say, they torque to their yield which is the point at which a certain material will permanently deform and loose it's clamping force. If torqued beyond yield, they are no good and need to be replaced. If they were torqued properly, then they can be re used.

They say to replace the TTY bolts because there isn't really any way to know if they were torqued properly, unless you torqued them in the first place.