Well I think there just ignorant to not want ppl to use a dowel with them. I don't see how a girdle won't help prevent cap walk? I'm sure billet caps don't do much atall, but a girdle can only help.
Main Cap Walk
- Thread starter schulte
- Start date
im with you there, im just saying from what ive been told by those more knowledgeable than me and read here, it wont completely STOP it.
The centerline has to change because you are raising the centerline of the circle by cutting the block to clean the cap surface.
The only way it wouldn't change is if you offset the line bore by the amount you shaved off the block.
The only way it wouldn't change is if you offset the line bore by the amount you shaved off the block.
Josh, you have to machine the main journal to change center line. Simply maching the mating surfaces doesn't change crankshaft center line. Again im no engine builder but I can't see this any other way.
Yes it does. The mating surface of the block and cap is the centerline of the bore, correct? If that is cut down on the block, how could the centerline not move by the amount it is cut? If you only cut the cap, I agree, it wouldn't change, but cutting the block, there is no way it doesn't change unless you offset the line bore by the amount you cut off the block.
The crank journals still sit in the same spot in the block so how does the centerline change?
Because both ends dont move closer when shaved and get bored out to the same diameter.... Only the cap comes in closer, because the bolts pull it into the block. So you'd have to shave off 2x the amount of the cap as you do on the block to keep a try centerline
The centerline of the crank doesn't change. When you align hone you use the original depth of the block as your starting point and the material comes from the main cap. Unless I'm missing something that is.
^This is the way I see it. The crank rides in the journal which is unmachined, you've only skimmed the mating surfaces. The journal is still untouched therefore the crank has to be in the same spot. When you line hone, still use the same center line, no material is removed from the block side journal, only the main cap.
It comes from both registers when honed in a normal circumstance. But the mating surface has never been shaved, that's why the centerline does not move in relation to the cam when bored or honed in a virgin setup. Pulling any surface off the block surface (like this situation(not just the bore of it, mate surface too)) and it will move the relation to cam closer.
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What point are you arguing? Maybe I'm just tired but your not making any sense.
It's gonna pull closer to the cam when shaved off the mating surface of the block.
EDIT I edited my post cause your right it was unclear lol
If you do anything other than knurl the caps and cut the caps you will push the crank up to tight against the cam gear in a gear to gear timing setup. The only fix I have ever seen is to use a larger housing bore bearing from another application and recut the tabs on a bridgeport. Than grind the crank accordingly. good luck to the next guy that gets the engine and has to figure out what you did in that case. Or you can bore the saddles and then cut a sleeve, you drill and tap the block and bolt the sleeve in with a flat head bolt and then rebore the whole block. I have only seen that in very expensive blocks as that process will cost about 1000 dollars.
Also when you cut the caps if they are spun out and not the saddles, be sure to use a diegrinder on the side bolt holes. I cut some caps and re line bored one and ended up pulling a side bolt cap thread because the bolt was pressing to far down on the block. I had to enlarge the hole by about .008", re tap my main cap, buy a new bolt and then tear everything apart and re tank and clean the block.
It is very hard to save a block with spun bearings
Also when you cut the caps if they are spun out and not the saddles, be sure to use a diegrinder on the side bolt holes. I cut some caps and re line bored one and ended up pulling a side bolt cap thread because the bolt was pressing to far down on the block. I had to enlarge the hole by about .008", re tap my main cap, buy a new bolt and then tear everything apart and re tank and clean the block.
It is very hard to save a block with spun bearings
It will move
Josh H is dead on. You can't clean up the bore unless you cut it. It will tighten up the gear. That's why they make chains for align honed blocks. They are shorter.
Josh H is dead on. You can't clean up the bore unless you cut it. It will tighten up the gear. That's why they make chains for align honed blocks. They are shorter.
Also
Dave C I have to ask if the same would work on a ring and pinion? LMAO Wade you better start back pedaling.
Dave C I have to ask if the same would work on a ring and pinion? LMAO Wade you better start back pedaling.