davidfarmer

I'll get the heads off after I get the car back together. I'm curious too, but I've got 2 other cars I need to get some work done on, and it will have to wait.

Engine is laying out in my front yard if anyone wants to pull the heads for me!

I had a local machine shop cut the motor mounts for me...much cheaper than running the VBP poly/aluminum units. Just for safety, I plan on richening this engine up a bit, and dialing back the timing, but it is all pretty much stock at this point.

I didn't elaborate my Atlanta story very well. When the trans locked in 3rd gear on the opening lap, I just kept trucking, running at redline for most of the track. Pegging redline for 40minutes isn't the best way to nurture an engine.

Cobra4B

^ Well damn... redline for 40 min... nice

0Randy@DRM

Make sure you have the steam lines in the rear open. Do not block them off like on the Z06. The back of the head will run hotter and cause all sorts of problems.

Randy

Racer-38

Jody, David..
I joined your club this weekend
National qualifying at Road Atlanta, second lap, first session, shifting form 4th to 5th on the back straight...car just died..no oil pressure. I broke the timing chain.
Car is at the engine builders now.

Cobra4B

Damn all you jinxers...

Falcon

I hate to hear that. Did it mess up anything else?

You could always use that other motor you have just lying around.

From what I saw over on the SCCA site, Chris and Phil were blistering the track.

Rollin Black

Randy, this is great info! Do you suggest the LS1 type steam lines? Or does DRM have a fix for this?

Thanks, Perry

0Randy@DRM

Either the LS1 pipes or if using a LS6 intake because those don't fit the only other option is some AN lines. -3 is more then big enough.

Randy

Cobra4B

Never heard of an issue w/ the Z06 coolant lines vs. the LS1 lines.

Rollin Black

Using an LS7 intake so AN lines it is. Again, great info thanks! I always wondered about problems closing those two back ports off.

Sorry for the Hijack David

Thanks, Perry

0Randy@DRM

Because nobody ever asked.

Randy
PS Sorry to Dave about the Hijack

davidfarmer

Randy, this is good to know, but I may be too far to do anything about it now. Is there something about the early LS1 heads that make the easy to damage, or are the later LS1/LS6's also having problems. I'm running a bone-stock LS1 with an LS6 intake, and don't really see cooling as an issue now that I have some gears to choose from and a good radiator.

0Randy@DRM

The pipes are the only real problem. Steam inside of a head is not a good idea. The reason for the steam port was to help remove the steam. Then came out the LS6 manifold, the 5 horsepower was great to sell cars and make dyno queens. There was no more room for the steam pipes under the intake. Next thing you know, hole 7 and 8 ring lands are breaking. It's not the only reason for the hole 7 and 8 but it sure isn't helping.

Yes the radiator is going to help the overall temps when it goes by the sensor. But the back of the head will run hotter. Think how hot a dry air locked bubble .150 inch away from that combustion camber.

Randy
PS Don't belive me, extend the sensor wires and run the sensor in the back of the passenger head. This is more the case at super high rpm when the water pump is doing what ever pumps at way too high of a rpm do. Cavitation I think would be the right word.

davidfarmer

In all of my high-HP cars, I never had a problem with this, but I will address it at some time.

How about pulling the intake and bleeding the close-offs at the back of the head. I always wondered how you were supposed to get the air back there, but like I said, I've never personally had a problem.

Live and learn.....

AU N EGL

That is for sure. Those two were flying.

AU N EGL

Is that part of why the LS2 block was developed? better oiling and cooling of #s 7 & 8? besides the bigger cubies

davidfarmer

that's part of my concern...the ls2 and ls6 use the same head castings, and both seal the rear steam vent, so any cooling enhancements would only help the block, no the the heads (ie the combustion chamber). I think I'll likely pull my intake after I get everything together, and purge the seels. If I can find an easy way to rig up a crossover I will, but this hasn't been a problem for me before.

I do purge air bubbles by pressurizing the system until I get lots of clean water out of the overflow return, but that only purges the main lines...doesn't really help any air trapped at the back of the engine. However, if you don't do it, you'll overheat an enginer lickety-split.

racerwannabe

i have a set of heads ,,one broken one not....aren't they interchangeable,,just in case you only have one broken...LS-6.....
Johnny

davidfarmer

mine are LS1 engines for now....but thanks.

yanked the heads off, and everything is mechanically intact (ie pisons, etc), While the gaskets are NOT dramatically torn, you can see where oil was bleeding in from th pushrod area, leaving 1-7 pistons very oily.

Number 8, which I figured was "broken", is just washed out with water, I assume. The piston looks steam cleaned, compared to the others. Again, no obvious gasket damage, but what can you do.

Anybody know the story about the gaskets mostly blocking the water passages? I'm not questioning the amount of water flow, but it seems like using the gasket to restrict water flow puts stress on the gasket itself.

I'm a parts assembler, not an engine/trans guy. In other words, give me a short block and I can put it all together......give me a trans, and I can put the car together. Nuances of gaskets, bearings etc are out of my knowledge bank.

Maybe Randy can chime in. Would be nice if we could get the Katech guys to visit the Road Racing section...but I think they're too busy selling $20,000 engines over in the C6Z06 section

Cobra4B

Can you post up a pic? At first you said you can see it torn, then said no obvious damage... which is it?


If the psitons look steam cleaned then coolant was definately in there.