LS7 build struggles - bore roundness
TECH Fanatic
Joined: Feb 2015
Posts: 1,080
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Honing has come along ways since the 70s when we used stones and set tension with a **** above the spring on the hone while looking for a "good" 45* cross hatch.
Check out the Rottler abilities at Surface details for different applications Mike Moran talking about the old days compared to using a Rottler
Check out the Rottler abilities at
Hi spanks 13. I don't know all the particulars about what I'm gonna tell you. But this should make you-And some others-Feel a little better. I'm sure some of you have heard of Cycle Magazine, which ceased production over 20 years ago. There was a story in the magazine at one time about either a Harley V-Twin, or a Ducati, V-twin. I believe it was a Harley. Anyway, I believe it was a guy named Kevin Cameron, a VERY highly respected motorcycle engine builder, who bought a used Harley racing bike. They ran it the way they bought it, and were unhappy with the power output. Cameron tore the engine down, and PRESTO-The cylinders were out of round .002"-.003"!!! With visions of instant power gains on his mind, he bored the cylinders .005" or .010" oversize, since you were allowed to go oversize, to compensate for wear, in the class they were racing in. He then put in new pistons and rings, put it back together, and gained absolutely NOTHING!!! They were baffled, and never did find out why the better bore and hone didn't net a power increase!!! He ended that portion of the story with 2 words: "A mystery". Just sayin', all may not be lost......
Thanks all for the input. Tony, especially, thank you for taking the time to write all that up. In the future I think I'll take your approach of getting another torque plate and dropping it at the shop that way. Eliminates so many variables.
Some not so great news, my existing 402 stroker in the car lost a lower radiator hose when I was basically in the middle of the canyons/forest. I wound up driving about 15 minutes total with no water in the engine. I changed the oil and refilled it with water and it is making some nasty noise under load and also gets way hot very quickly. I think I have a knock internal somewhere, and also combustion gasses must be getting into the coolant. Pretty sure the whole thing is toast. Should've parked it and figured out a better plan but it is what it is. It was valentines night on Sunday and I didn't want to try and get a flatbed tow on an almost 1 lane road 20 minutes into the canyon. The engine owes me nothing. Just sad it was a stupid radiator hose.
I'm now immobile, and won't be able to sell my old engine which unfortunately I basically had sold already for $6500 intake to pan. I wasn't really wavering anymore on the idea of assembling the engine as-is, but now there's no question. Hopefully it dynos well and I can drop it in the car.
Some not so great news, my existing 402 stroker in the car lost a lower radiator hose when I was basically in the middle of the canyons/forest. I wound up driving about 15 minutes total with no water in the engine. I changed the oil and refilled it with water and it is making some nasty noise under load and also gets way hot very quickly. I think I have a knock internal somewhere, and also combustion gasses must be getting into the coolant. Pretty sure the whole thing is toast. Should've parked it and figured out a better plan but it is what it is. It was valentines night on Sunday and I didn't want to try and get a flatbed tow on an almost 1 lane road 20 minutes into the canyon. The engine owes me nothing. Just sad it was a stupid radiator hose.
I'm now immobile, and won't be able to sell my old engine which unfortunately I basically had sold already for $6500 intake to pan. I wasn't really wavering anymore on the idea of assembling the engine as-is, but now there's no question. Hopefully it dynos well and I can drop it in the car.
