Happened a bunch back in the days because of a bad casting batch. However almost all of them snapped at the cam sprocket so you would know without pulling the cover, and of course the carnage from said sprocket falling off the motor.

What cams are you using Biggiesacks and where are you in the bay area?

Also, I would like to also do this in reply to your coil mistake: HAHAHAHAHHahahahhaHAHAHAH I would have been on the floor laughing if I was there, after checking that you weren't dead of course.

 

Pretty much as South as you can get and still consider it the bay area, around where the 85 meets the 101. So these are the revised HKS 274/278 cams that i got for free when i bought one of the first run HKS GTII 7460R turbos. I am also using the springs they included in the kit. I think i super lucked out where this thing snapped. All the valves post snap are closed and seem to want to stay that way. No amount of spinning of pre snapped cam opens any of the post snap valves. I guess this explains why compression on #1 looked 30psi higher then the other 3. No metals debris that i could see, ill have a better look when I have daylight.

 

Very interesting. Time for some GSC billets and new valve spring kit. I'd pull the pan, make sure there's no metal bits in it.

 

Damn that sucks, looks like you are going to need to rebuild the head since some valves might have bent.

 

I thought those cams failed on mivec oil ports. Didn't know exhaust cams broke as well. Dang, that sucks!

 

How lucky are you? Cam snapped but all valves of snapped portion remained closed! Go buy a lotto ticket!

 

I think im going to do exactly all of that


I am going to check, and if any valves did bend I will be pulling the head. It really seems like that didn't happen though, the spot it broke in lets all the post snap valves stay fully closed, and they want to stay closed, and the pre snapped part is basically still perfectly intact.

Not only that but # 1 is fully intact and kept the belt aligned the whole time. The hotrod gods are smiling on me

 

The cam does seem to rotate a bit easy for any valves to not be bent. Easy way to tell would be to just do a quick leak down test while the cams are out. Then you don't have to remove manifolds to do a visual.

 

The gore






I'll be replacing that scored rocker on #3 as well.

 

That engine has 160k miles on it???? What oil do you use and what drain intervals? She's squeaky clean in there. Very impressive.

 

Thanks that's a good idea, added to the list. It really is crazy how this broke, the cam has a very large travel before any of the lobes start to ramp up, its like a big flat spot that the cam was resting in, so fingers crossed.

 

Exactly. Buy me a lotto ticket while you're getting yours!

 

And change your valve stem seals while your springs are out.

 

Not gonna lie, if i bought 2 and one of em hit that one would be mine but you guys would get unlimited free time on my dyno

 

On the list, for some reason my exhaust seals are already leaking again after only ~30k miles on the rebuilt head. Open to any ideas on that one.