Blow by
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Intermediate
Joined: Oct 2015
Posts: 30
Likes: 3
Blow by
Hey guys I got an 02 zo6, I had a freshly redone forged ls3 dropped in with an a&a kit, just about 3 months ago. I took it to the tuner recently and on the 2nd small pull to about 5k, oil shot out of the breather and got everywhere. Afterwards on idle theres a bit of smoke coming from the oil filler area. Now Im pretty certain that its gonna be the rings, because the same thing happened to me back in about august. I got the same ls3 had an unknown shop tear it down and build it back up with stock pistons rods etc. It only took a few pulls before it was steaming out at idle similar to what I get now just worse. Once it was tore down cylinder 7 had a cracked ringland and that's when I decided to forge it. My question is how could this have happened again? The motor looked solid and the engine builder has alot of experience. The tune wasnt far off, and I wasnt beating on the engine previous to the tune session just the normal break in procedure. Let me know what you guys think.
Racer
Joined: Jun 2004
Posts: 270
Likes: 67
From: Montana
Was the ring gap increase? What I understand cylinder #7 and #8 run a little hotter. If the ring gap is too tight plus the extra heat, breaking the ring gland might happen. My LS3 wasn’t blown but I had #7 ring gland break off. Possibility I screwed up the tune, I was just learning how to tune and ran it a little lean. While repairing it, I researched it and I increase the ring gap on #7 & #8, a few thousand, can’t remember exactly this is about 10 yrs ago. Plus add the the cross over coolant line on the back of the heads to reduce the heat build up.
Last edited by robmiz; Mar 25, 2021 at 11:06 AM.
Race Director
Joined: Oct 2004
Posts: 12,795
Likes: 4,614
Was the ring gap increase? What I understand cylinder #7 and #8 run a little hotter. If the ring gap is too tight plus the extra heat, breaking the ring gland might happen. My LS3 wasn’t blown but I had #7 ring gland break off. Possibility I screwed up the tune, I was just learning how to tune and ran it a little lean. While repairing it, I researched it and I increase the ring gap on #7 & #8, a few thousand, can’t remember exactly this is about 10 yrs ago. Plus add the the cross over coolant line on the back of the heads to reduce the heat build up.
Racer
Joined: Jun 2004
Posts: 270
Likes: 67
From: Montana
I know this is off topic, and I'm not trying to be a know it all wise ***. But, it is a ring LAND, not gland!! Glands are in mammals, and other creatures, NOT pistons!!! Our engineers at where I worked did this same thing. On the blueprints, they called it a ring gland. The only thing I can figure on this is some engineer, long ago, ran the two words together, forming the non word 'ringland'. It's a mechanical 'land', a flat area as it relates to the rest of the pistons diameter. You are correct on the ring end gaps. Greater gaps are needed if running a power adder like a turbo, blower, or nitrous. They'll butt ends if not sufficiently gapped, then BOOM!!!
