Rich2342

iTrader: (1)

UPDATE*******

Well, cylinder number 7 is cracked as well as piece of the piston at the top.

There are 2 theories I am seeing as to why:

1. I was running the Ls3 OEM Camaro Fuel pump w/LS7 injectors. Possibly went lean at 7k?

2. The rear steam ports were blocked off when the Brodix heads were installed. Could the pressure have built up and cracked the block?? Shop said it hydrolocked and after pressure probably built up in the cylinder.

Ryans99ls1

iTrader: (16)

Cracked a piece of the piston or just broken/shattered in general? Being lean can cause ringlands to pop - too much heat and the rings butt and pop a piece of the piston off. It bound up even more and cracked your cylinder. Idk enough about that fuel pump but it is either not strong enough OR your fueling/tune was just off in general. You should have a wideband installed on the next go around..

Many LS7's and LS's in general running around with rear steam ports blocked. That being said, popped ringlands were a very common failure in the early boosted ls1 days and most swore you needed to have the rear steam ports in use. It can't hurt.

1FastBrick

iTrader: (16)

Without seeing the actual damage, You likely butted a ring as mentioned from going lean which broke a piece of the piston off.

Depending on how big it was, it can damage the cylinder and take out a sleeve bouncing around in there.

spanks13

iTrader: (5)

Was this engine tuned before you ripped it, or was it running with the tune from the LS3? LS7's aren't the most durable but it is really difficult to blow an engine like this NA. Sorry about your luck.

jayyyw

winner winner chicken dinner

Sorry this happened tho. Good luck with the rebuild.

Rich2342

iTrader: (1)

She was tuned. Had ported intake throttle body, milled ported heads and cam. She was damn strong.

Maybe steam port, maybe the fuel pump couldnt keep up.

Had a convo today about it. And Street sustained RPM under load is of course less severe than a quick dyno pull. Possible that things werent apparent on the dyno vs going all out under load and rpm.

We did street driveability in between the dyno as well, but no hard sustained pulls.

Rich2342

iTrader: (1)

Would it shoot out the exhaust? Someone said it is likely.

Che70velle

iTrader: (6)

It can happen, yes. I’ve seen marks on all 8 pistons, from a carb squirter screw that backed out at a sustained 8500 rpm. One screw. It removed a piston ultimately. Said that to say, that debris can and will get back up into intake from reversion and also scoot out exhaust. Question for you here…is the chamber hurt on that cylinder?

Rich2342

iTrader: (1)

It awaiting an LS3 vette motor. Yes #7 piston has a crack near top of piston and the sleeve also is cracked by the water jacket I am told.

My question for the swap. What can I safely reuse? What should be replaced?


1. mishimoto oil cooler
2. Wondering about the HFC's on the headers?
3. LS3 oil pan was modified for the ls7 crank and oil cooler.
4. MSD intake. I believe unscathed...phew wont fit LS3.

Anything else I am forgetting or should have checked?

Rich2342

iTrader: (1)

My first LS3 dropped a valve and ended up in the intake among other places. Scarred it.. I've had some luck..