My Camaro went home to Oshawa to die......

[2010 SS RS]

Originally Posted by Huggerorange73

I think the other part is people are blowing past the limits of the OEM rods & pistons.

The cranks are good to around 900HP...the rods & pistons...not so much.

Mike you sure said that well. Powder forged rods, alum cast pistons...Add power, be too lean and kapow! Catistrophic failure! Been there and done that myself and have a slighltly used set of 7 pistons if anyone wants some..bahahahahaa

[Huggerorange73]

Okay, the front cover is off...those of you that had cam pin sheared off as the failure point....YOU WIN!

Although we stil don't know if the pin snapped off first, or something else caused the pin to shear.

[PQ]

Chain tensioner is still good too. So the chain did not slip or break a tooth. But the cam just turned.

I'm going with the hard loaded violent torque hit from the tranny failure did the deal.

But, you are right. We will never know now.

[cndcamaro1ss]

if you want to read a good write up what can go wrong when doing mods to your camaro,s,read the june issue of HOTROD mag some good info.

[garcmol]

So this pin in essence is what holds the cam against the gear? That and the torque from the bolt? So does the 3 bolt you guys talk about eliminate the pin and make it stronger?

I can now say I know what a cam turning (not the way it's intended to) looks like.

[Huggerorange73]

Originally Posted by PQ

Chain tensioner is still good too. So the chain did not slip or break a tooth. But the cam just turned.

I'm going with the hard loaded violent torque hit from the tranny failure did the deal.

But, you are right. We will never know now.

Nope, we'll never know what happened first...but the lesson I'm hoping to share with all of you is to do the 3 bolt conversion!!!!! And change the lifters too!!!!

Originally Posted by cndcamaro1ss

if you want to read a good write up what can go wrong when doing mods to your camaro,s,read the june issue of HOTROD mag some good info.

Hell...I could write that article!

Originally Posted by garcmol

So this pin in essence is what holds the cam against the gear? That and the torque from the bolt? So does the 3 bolt you guys talk about eliminate the pin and make it stronger?

I can now say I know what a cam turning (not the way it's intended to) looks like.

The pin is a locator/guide.....the bolt along with that pin should hold the gear in place.

This is the bad part of the single bolt setup....if you have a failure, you're toast. The odds of a failure like this with a 3 bolt set up would be very, very small.

[Camarowguy]

When the lifter bore broke, it probably stopped the cam shearing the pin. That's my guess. Why did the lifter get cocked like that and break the block? Who knows. I have my theories.

[Huggerorange73]

Originally Posted by Camarowguy

When the lifter bore broke, it probably stopped the cam shearing the pin. That's my guess. Why did the lifter get cocked like that and break the block? Who knows. I have my theories.

Let's hear them...now we're going to play House MD on my engine!

[mikeSS]

wait so we will never know what happen first ?

[GMGP5X]

Originally Posted by Huggerorange73

Let's hear them...now we're going to play House MD on my engine!

Web M.D. for engines.

[Padre]

Originally Posted by Huggerorange73

Let's hear them...now we're going to play House MD on my engine!

You mean we all have to be sarcastic, narcassistic, pill-popping, drama queens who come up with the solution out of the blue with 5 minutes left in the show?

Padre

[Huggerorange73]

Originally Posted by Padre

You mean we all have to be sarcastic, narcassistic, pill-popping, drama queens who come up with the solution out of the blue with 5 minutes left in the show?

Padre

Exactly....pass the vicoden please.

[mercedestech]

That pin isn't supposed to see any stress at all. It is merely there as a locating pin when installing the gear. The bolt is supposed to hold everything together. I know it seems like a crappy design, but even Mercedes uses it in their 6.3L AMG engines. Infact the Benz engine doesn't even have a pin, we have a special tool that lines everthing up (cam, cam sprocket, chain, etc) while we tighten everything down. Now mind you these are overhead cams with no pushrods etc, but still a very similar design as far as the holding the cam sprocket to the cam (the Benz cam has an adjuster for cam timing not just a sprocket, but very simialr). You guys probably don't care, but I just thought I would throw it out there that a very advanced high horsepower engine made by Mercedes uses a very similar techniquie to hold everything together....and I've never seen one fail. I'll apologize now for getting off the main topic, I just want to know why this keeps destroying LS3 engines. This thread bothered me so much I just sold my TSP cam. I'm going to hold off on a cam until we know why this is happening and I'm closer to being out of warranty......It would take me months to recover from a failure like this without resorting to charging up the plastic! I'm all about paying to play, but damn......this would suck no matter how much money you have in the bank!

[Russell James]

Originally Posted by Camarowguy

When the lifter bore broke, it probably stopped the cam shearing the pin. That's my guess. Why did the lifter get cocked like that and break the block? Who knows. I have my theories.

I'd bet the lifter, PR's, valves, pistons, rods, block.... all that stuff was victims after the cam gear turned. When a piston hits something solid at that RPM, especially with stronger than stock PR's, it can easily blast a lifter right through the block.

I think the question is why did the pin shear? Was the bolt shoulder bottomed out on the pin instead of gear. That bolt/gear/cam needs to be held in by 360 degrees of that bolt shoulder. If one side is cocked by the pin - the gear is going to be unstable. Pin could be too long, hole in cam not deep enough...

If no defect in the pin/bolt mounting, my next guess and I think most probable is harmonics beat up the dowel pin until it failed. The stock set up was engineered to run for days at 6600 rpm, full load, no bad harmonics. Now, change multiple things in the valve train, valve springs, PR's, cam lobe profile, balancer, raise the limiter.... will it still have no harmonics beating up the timing chain? That entire combo would have to be Spintron tested to know. Did Comp Cams Spintron that cam, those springs, PRs, balancer... and see no bad harmonics at 6800 RPM?

I'd call Comp Cams and see what they say.