StreetSpeed

Folks,

Blew my stock ls6 at the start of qualifying last weekend. Came out of the pits, ran to the top of second to shift to third and kablooey. Didn't even make it past the blend line. Was totally bummed since it was my first time qualifying after completing race school the previous day, and in the morning practice I was 4th overall on my first time on sticker Hoosiers. Also first time blowing up a motor, getting towed, and ruining everyone's qualifying session.

Anyway, don't know the exact failure yet, but the left side in the bottom of the block has a big *** hole in it. Coincidentally I received an email from Titan oil analysis that said the copper in the sample was high. A quick search revealed that LS motors tend to have a higher copper content than others, so I don't know if mine was high comparatively or not.

Trying to figure out what I'm gonna do for a motor in the near future. Hard to find decent LS6s it seems, and my mechanic wants to build an LS frankenmotor with big torque and reliability for ST2.

Anyway I guess my question is has anyone had a similar sounding failure? Ever able to put a finger on what happened exactly? If it was a high G turn I would have fewer questions, but since I was headed straight I wasn't exactly expecting it to pop with no warning.

ZedO6

What year motor and did it have original valve springs?

RX-Ben

oil temp? water temp? miles?

96CollectorSport

That sounds like a rod bolt(s) to me. If you have a big hole in the side of the block see if the rod is still there, or if you can find the rod cap in the oil pan. You should see a rod bolt that was stretched, it will kind of look like taffy where it stretched and separated.

tmtraylor

Condolences and interested in the results and analysis. Good luck going forward!

Tim

StreetSpeed

Oil temp and water temp were however hot they get waiting in staging for 5 minutes on an 80 degree day. I'm guessing plenty warm, but certainly not over hot. This was literally coming out of the pits for the first lap. Engine was an 04 with 47000 miles on it, all stock internals including valve springs.

blueekb

I blew up same exact way coming out of Oak Tree at VIR back in May of last year. Going straight in 2nd I hit the limiter twice by accident. Then went to shift and boom before I even let the clutch out. Stock 03 Z06 with 80,000 miles.

I finally have some money to spend on it so I started tearing into it. Just started but i've found a ton of metal and oil in the intake. Valve springs and push rods look good. I hope to have the heads off this weekend.

I am having a hell of a time finding anyone to build me a motor that makes stock power and does not cost a fortune. I have several quotes at or over 10 grand for just a long block and me doing the work.

It sucks because I call these shops and they say they can build me a forged motor for $7000 but then I get a final quote and its no where near that. I just want stock power not a 700hp monster!

JerryTX

I lost a stock LS2 kissing the rev limiter at the top of second for less than a second. (You can fast forward to minute 13 and watch it ). Many valves kissed pistons, 3 valve heads snapped off, bounced around, finally shattered 2 hypereutectic pistons, loose connecting rods slapped a hole through the block, oil hit headers, things got hot.

I think your stock valve springs were not enough to keep the valve in contact with your cam, leaving it in the way of your piston.

StreetSpeed

Ed,

I hear you. I'd always heard about the $4500 Ls6 crate motor. Pay someone to drop it in and you're out the door for less than 6. Seems those days are gone (or never actually existed).

So I will be going with one of two options:

Stock donor low-mileish LS6, upgraded oil pump, valves, springs, timing chain, cam, and tune to make 400whp 400 wtq. This would cost something like $8500 installed.

My other guy wants to build a cheaper motor and get a little more creative and address reliability issues more than the first guy. So he's thinking LQ4 6.0 iron block, lots of custom head-stuff from Straub Technologies, Accusump, MTI Oil Cooler, and other reliability things. Looking for 400whp and 520 wtq with this setup. Sounds good for ST2! Also somewhere around $8500 installed.

My car is a full race car now, so I'm leaning towards option 2. If the car pulled double duty as street and track I'd probably lean more towards option 1 as a better OE solution. But I'm still waiting for quotes from both guys, so not sure yet what's gonna happen.

Good luck with yours. PM me if you want more info on mine.

blueekb

LS6 crate motors were $3500 or less I think it was back in 2010 or so. Sadly they are all gone. I have seen some pop up on LS1tech from time to time around the $4500 to $5000 range. I just think for that much I would rather get some upgraded internals like your first option.

People try to sell 75,000 mile LS6 motors for around $3000 I think its crazy and not touching that.

I would love to find a budget friendly way to make more torque but same HP as stock but it looks tuff without restricting the motor big time. Iron block route sounds cool but I believe they are at least 50 pounds more which we don't want that weight out front.

If I have no luck finding anything for a decent price I might just sell my rolling chassis and get a Spec E30 to race and be done with it.

StreetSpeed

50-80 lbs with the iron block. I can still take out my head lights so that's 30 or so pounds. I'm pretty sure I won't even feel another 50 lbs in the front with a proper setup and counter balance. I moved to a small battery and took out the AC condenser (something like 60-70lbs total) and felt just about nothing.