Hey Mike, The spings were good (new) Comp 996 1.625 diameter set up for 330# closed and 850 open. The .060" was intake, exhaust had a little more as less lift and more lash.

Yes i think it did spin a bearing first, because the broken pieces of the rod cap were nice and blue...

Piston is melted not broken.

Yes the spark plug from that cylinder is nice and silver... coated with piston.
The rest of the plugs looked fine, so i have to check the line, and nozzle to that cylinder.

Scored the cam on a few lobes and one set of lifters is stuck in the bore so will need replacing...

Pretty much a total loss except the head castings.

Oh well, I will be back bigger and faster in a few weeks.

Cheers,

Arnie

You have any more info on what you think might have caused this yet? Although burning a piston from being lean is more prevalent on stack injection because of the individual runners it can still happen on plenum injection although it has to be really really lean unless you have a bad injector nozzle. I will be curious to see if you come up with a cause.

Howard

Well I found what melted the piston...

Clogged nozzle on the #4 cylinder which had reduced the nozzle area by at least 50%.

glad you found the cause.

Howard

Here is a clear nozzle.

now here is the clogged one from #4 cylinder...

Bummer...Sorry for the carnage but I suppose it could have been worse. Maybe time for a set of EGT probes to keep better tabs on the bullet.

Good detective work.

Alcohol can clog a nozzle pretty easy. From the little I have seen/heard, using top end lube in the alcohol can help reduce this. Typically they can be easily cleaned by putting the nozzle jets in gasoline to dissolve the crystal/gummed up alcohol.

Ouch, that really hurts.

Yeah it does hurt...

But, I will be back stronger and faster w/ a 540ci Alum lowdeck motor in September.

You can bet i will be checking nozzles next time... I only made 6 passes total spaced 1 week apart, but apparently that is all it takes.

Thanks for reading along!

Arnie