How many have had them? Freind of mine broke one on his HD the other night racing a Lexus, I think.

Well you know what happened then right? valve hit the piston with authority, then ended up spitting peices of rod, wristpin and piston right through the oil pan.

Wrecked his night....its his daily driver...good thing we have the motors laying around at the shop though. Makes me doubt the ol' 918's with such a mild cam. His was a custom grind but it was very small. 220/224 572/578 114+4.

Now he is putting one that is at the shop. lol. It happens to be a 6.0l iron block with 2e heads and a 233/239 TSP cam. lol gonna be one mean HD to mess with.

 

How many miles?
installed height etc...

 

Also, were these the blue stripe or prior version?

What RPM was he spinning to?

 

Truck warmed up or did he just hop in and go...........?

 

I had the blue stripes on mine are those the the updated ones? 2e heads?

 

blue stripe is the newest. 2e heads are from MTI.

 

Yes they were blue stripe, they had about 20k on them. He was spinnig to 6450 on the 1-2 shift and 6300 on the 2-3 shift. The 2e's he got are indeed MTI heads and they have their dual springs that are good for .650. I have done my share of cam swaps and this was a first for me on a 918 so I was just looking to see if there was other failures like this.

 

20 K is nothing to be ashamed of. These springs should have been checked prior to this mileage.
Some have gone a lot more, but there is a lot about this that is unknown.

 

When he brings the motor over I will check seat pressure, open pressure, coil bind and all off that good stuff.

 

That would be interesting information to review.

 

Who ground the cam, who made it?

Was it the Z-220 cam from SDPC?

 

.570+ lift on both the intake and exhaust on a 220 and 224 lobe, those springs didn't owe him anything. That's fairly agressive lobe. It's generally accepted that you change or check springs at 10-15k mile intervals with that type of lobe profile.

 

I've got about 4k on my 918's with a TR230/224 and I'm already getting nervous. I'll probably change them in another 6k just to be safe though.

 

ive got 25,000 on my 918's and it sees 6800 all the time. Hey if they cant hang then they gotta go.

 

I would be very nervous on a 918 spring with 20K.. hell I wouldnt even go there.

 

Guys, I've taken 918's to 18k with .610 lifts. All were still within specs.
You do not have to change them every 10k.
THAT IS A MYTH
All you have to do is do spring maintenance, which is measure seat pressures and install heights. If within specs, they will be good for another 10K.

Please do not start this 918 PHOBIA again.

 

I've got 12k on my 918's w/ the TR224/112 .563 cam and have never thought twice. No problems and I spin 6500 frequently.

 

Got a how to so I can check them out? Otherwise i'll just pull them every 10k since I can't be sure. Also, if I have to pull them to check them I might as well just change them.

 

I personally don't think measure load will help, these springs are pretty hard material and any failure will be quick and catastrophic. I plan to go by miles (# of cycles in fatigue terms).

 

Those springs will fall out of specs and sag.
#1 reason of their failure is improper warming to operating ops,
# 2 is improper install as per cam requirement.