ZR-1 Net Registry Forums - View Single Post - Secondchance

secondchance · 03-22-2014

Thanks, Lee! Can't wait to mate those IHs and the plenum, finished in Tiger Drylac anodized silver, back on the heads!

Disassembled motor was dropped off at the machine shop today. Of course, I was totally lost until Phil showed up and started talking to the shop owner. Lloyd, the owner of the machine shop, obviously was a total gearhead and I could tell how much he was enjoying talking to Phil. Also got a tour of the shop.
Phil and Lloyd did some forensics on how I ended up blowing exhaust into the cooling system. If I understood correct, it was a combination of mileage and a defect on the head gasket.
Mind you, both head gaskets were intact - no distortion.

Below is the 1-3-5-7 head. Problem was with the #5 cylinder.

Cylinder #5 - notice the notch?

Corresponding segment of the head gasket.

Interestingly we found a "v" shaped depression on the other head. It turns out head gasket had a small imperfection, which was quite visible, responsible for this depression.
Perhaps, there was some over-heating due to low coolant when the OEM radiator went that exacerbated this weakness.

Whatever caused the sequence of event, this LT5 served me and served me well for the last 13 years and 140,000 miles. Better yet, I get to have a hand assembled 4" by 3.75" 377!!! - I LOVE IT!!!
I have always loved cars and especially Vettes. Owned Vettes since 1979. However, had I not run into the Net Registry and WAZOO in particular, I wouldn't have known of what can be done and couldn't have even dreamt of 380 build.

Thank you Net Registry and WAZOO!

03-22-2014	#59
secondchance Join Date: Aug 2006 Location: McLean, VA Posts: 3,730	Re: Secondchance - 380 build begins! Thanks, Lee! Can't wait to mate those IHs and the plenum, finished in Tiger Drylac anodized silver, back on the heads! Disassembled motor was dropped off at the machine shop today. Of course, I was totally lost until Phil showed up and started talking to the shop owner. Lloyd, the owner of the machine shop, obviously was a total gearhead and I could tell how much he was enjoying talking to Phil. Also got a tour of the shop. Phil and Lloyd did some forensics on how I ended up blowing exhaust into the cooling system. If I understood correct, it was a combination of mileage and a defect on the head gasket. Mind you, both head gaskets were intact - no distortion. Below is the 1-3-5-7 head. Problem was with the #5 cylinder. Cylinder #5 - notice the notch? Corresponding segment of the head gasket. Interestingly we found a "v" shaped depression on the other head. It turns out head gasket had a small imperfection, which was quite visible, responsible for this depression. Perhaps, there was some over-heating due to low coolant when the OEM radiator went that exacerbated this weakness. Whatever caused the sequence of event, this LT5 served me and served me well for the last 13 years and 140,000 miles. Better yet, I get to have a hand assembled 4" by 3.75" 377!!! - I LOVE IT!!! I have always loved cars and especially Vettes. Owned Vettes since 1979. However, had I not run into the Net Registry and WAZOO in particular, I wouldn't have known of what can be done and couldn't have even dreamt of 380 build. Thank you Net Registry and WAZOO! Last edited by secondchance; 03-22-2014 at 12:34 AM.