thanks stu, but because I don't have the time either, the truck is with a engine guy as I type. I should hear from him today after he gets it torn down, but I will let you know if I need any of those parts.

And the valves with the bad lifters seemed to open and close fine, the valve with the broken spring will open/close but not well.....

 

I am seeing this now as I read some more sources. There is definitely conflicting data on the max lift of these springs, thus far I have seen 550, 570and 580. I know several people have run this cam and spring combo for 30-60k mi without a failure. I from a few threads it seems the 918's have the same problem though as well, despite the higher lift capability. Though not necessarily with this cam.



I am still left with what to do next once I hear from my engine builder.....
Maybe I just got a bad spring....maybe it will be fine.....maybe my block will develop a new air vent.

 

I have been running the GT2-3 for almost 3 years with the yellow ls6 springs. No issues as of yet. (knock on wood) I bought the cam and springs as a kit as well.

 

Checked and the springs were new. chevy parts dealer on ebay is who I got them from and they quote the lift good to .550.

 

I am also running the same cam N/A. the stock pushrods are 7.4 so its not the rods...and from wut i have seen the springs should have worked well until you start putting boost through the motor which with those small springs would cause valve float...sounds to me like you might be a tooth off on your timing chain causing the valves to strike your pistons...and thats not good...

 

The new 918s dont break....Patriot golds all the way though!

 

The new 918's are pretty much 928's, from what I was told. I had a 918 break and had no symptoms until the springs were changed out with the new design.

 

i had no problems with my 918's but i definately feel better after getting the patriot golds.

 

are you sure that the timing gears were dot to dot ? . . .

 

Yes I checked that several times when I did the installation, knowing that would definately kill things. I lined them up after putting the crank gear dot at 12 o'clock. Moved the crank by rotating the motor both directions to make sure it lined up perfectly, and to be sure I took it around 360 degrees and it came back fine.

Would it have run well for a week before I had problems if the gears were off by a tooth?

I will ask my shop if they checked that for me. I spoke to them yesterday and the pistons had no evidence that they struck the valves. They are replacing some valves (2 exhaust and one intake), getting a new set of springs and are checking on if some LS7 springs would work, getting all new lifters, and after the springs are decided they will do a valve job on the heads to ensure proper spring height. THe builder was concerned that due to the lift of the cam the springs bound and caused some of this. It should be done today. Assuming they don't have to tear down anything else.