http://www.lxforums.com/board/showth...t=68960&page=2

Apparently we have an expert in here, he was going to post on here as well, but he is yet to be seen.

He thinks the cams were too big for the springs, but I think someone has broken them with a stock cam correct??

 

Springs binding from too much lift...be it from the cam being too big for them or from nobody checking installed height? I know a LOT of people running 918's without problems at all...but then again most of them asked me to install them, and I check the installed height when I do it, and I also make them run an oil temp gauge and I usually explain to them to think of it more as a gas pedal gauge...don't hit the gas pedal until the needle is over here .

I will agree it seems awfully strange to see it happening to so many people in the same spot on the spring every time...but there are a LOT more out there that aren't seeing this problem at all...nobody posts a new thread every 10K miles just to say "hey, my valve springs are still not broken".

 

Man that is just terrible. I feel for you guys who have lost motors over this. I would try to get Comp to cover the costs but I am sure they wont even consider it.

I caught my busted 918's before any valves dropped.

 

Could this be why we don't hear as many broken spring stories as we should? My car ran fine with the broken springs for probably a couple thousand miles, of course, I have no idea when they broke, I just know for a fact that my car ran well with broken springs. I only pulled the valve covers after learning I had one of the bad batches. I bet many people THINK their springs are fine, when in fact they are broken; maybe on the verge of dropping a valve.

 

My rep at Comp just called and someone there wants to speak with someone with a broken spring....not in e-mail, not hearse on the net...they want to talk with someone. If you've actually got a broken spring, please call me so I can get your contact info and I'll have Comp call you directly.

Sorry I don't know more of what they want to talk about...he just asked me to get them in contact directly with someone. I'm here until 6:30pm central...800-456-0211 and just ask for Matt.

Thanks!

 

Thanks Dr. Jeckyl!

 

No problem

 

speed_demon24 got it right and nobody listened. Peterson American Corporation (PAC) was making the 918's and now Comp is sourcing them from another company. It's NOT an installation issue!

 

It has everything to do with Comp switching suppliers. The batch numbers I have seen comfirm this.

Comp switched manufacturers from Peterson Spring (PAC Racing) in early 2006 to one of our competitors. We made the original 918.

You can get the original 918 still through us. The new part number is PAC-1218.

We also ahve a bunch of other really cool LS1 stuff. Like the next evolution of the 918. The PAC-1518.

Feel free to ask me any questions. I run PACs valvetrain dynamics lab.

Please spread the word as we can't hit all the websites to warn people.

If the batch number is 29XXX and lower you have the older 918s from us. Anything else and you have the newer ones that appear to be failing.

 

Oh and I am trying to do this without soliciting as much as possible but it's hard not too. I think that this problem is large/important enough that this infomation is valid. I took out any contact info.

 

The PAC-1218 is also available from Crane Cams Inc. under Crane part number 99831-16.

 

Yes it is.

 

What is the big diffrence between the 1218 and the 1518 springs. I have the 1218 springs and I was wondering at what point they should be replaced regarding certain amounts of lift.

 

interesting.....

 

We recommend our PAC-1518 for anything above .600" to .650" lift because of the higher stress range. It's also a better spring for engines that will be turning higher RPMs or using a camshaft with aggressive ramps. The nitriding and other added processes we do give the springs even better fatigue life then the 1218 and can handle more punishment. I have ran the 1518 from free length to solid on our testers and haven't been able to break one after double our normal test length.

The 1518 is the next evolution of the 1218 (918). It gets a lot of the same processing that our cup springs do

 

??? Do these come with retainers? If so, what type???

Thanks

 

Sorry they don't , we're working on a package right now, but for retainers you will have to use Comp/Crane/Manley etc. Whatever fits the 918/1218s will fit the 1518s.

 

The Crane part number for the Titanium retainer is 99637-16.

 

Thanks...

 

I think it would be easier on all of us if Comp would just release the batch #'s of the bad springs from a year ago...