[monsterbaby]

I just finished pulling down my 528 that I run in my mud drag truck. it's a 4.3 stroke crank, 4.420 bore. the block is a 2 bolt D9TE block partial filled, and I ran the canton main support halo girdle with ARP bolts that cam with it. What I found was there was absolutly no signs of cap walk with this setup at all. I brought this up cause I remember last spring a lot of discussions about it, and it had me worried a little but like I said virtually no evidence at all. Also the main bearings showed very little wear and only one rod bearing had a spot that was through the top coating wear by all appearences it must have gotten a piece of debris in it on assembly, I am thinking something was missed in teh oil hole in the crank when I assembled the engine as it's right next to wear the oil hole comes through the crank and it's not bad at all the mark on the crank isn't deep enough to catch a fingernail on at all and the mark in the bearing is less than 1/16" wide.
I shift this engine at 7200 and regularly spin it 7800-8000rpm so I am thinking the main girdle with bolts definatly does it's job.

 

[Lem Evans]

It seems that you had the tuneup right . Too much timing and/or a lean condition will make the caps walk no matter whose girdle/halo is on them .

 

[Jon]

Lem hit the nail on the head.....

Good tune goes a long way against cap walk....

 

[motorvator]

I'm curious, how does to much timing cause cap walk? :?

 

[Jon]

to much timming....

If you fire the plug too soon it will explode the gas before the piston is in the correct place to take advantage of the explosion. To much timming can cause detonation which in turn is trying to force the crank out the bottom which cause's cap walk.