main bolt to stud, line hone?

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jamie
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Re: main bolt to stud, line hone?

Post by jamie » Sun Dec 26, 2010 10:49 pm

Thought I would drag up this old post with this question.When there is evidence of cap walk[fretting] is the block junk or can it be saved provided you found out why it was walking in the first place?

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Wolfplace
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Re: main bolt to stud, line hone?

Post by Wolfplace » Mon Dec 27, 2010 12:20 am

jamie wrote:Thought I would drag up this old post with this question.When there is evidence of cap walk[fretting] is the block junk or can it be saved provided you found out why it was walking in the first place?
Yes it can assuming it is a block that is worth something.
You machine the block surface flat. Kind of the reverse of cutting the caps
In most cases I feel it would be best to go to a wider cap like the Program stuff to regain a locating register because chances are the original one is going to be beat to hell & you can only do so much with a damaged register to tighten it

Also if it has been worked hard enough to fret the caps you want to look at the webbing real good for cracks too.
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bentvalves
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Re: main bolt to stud, line hone?

Post by bentvalves » Sat Mar 10, 2018 8:51 pm

Im reading an engine building book in which the author states when line boring or line honing it is best to be on "bottom side" of the specification.

His train of thought goes something like - better bearing crush, better heat transfer, less chance of spun bearings.

It has been pointed out in this thread that most builders like to be on the top "top side" of the specification.

anyone care to iron this one out for me?




- if the crank was going to be ground, I suppose I would want my housing bores "bottom side" and have the crank pins ground to where I would get my desired clearance.

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Re: main bolt to stud, line hone?

Post by modok » Sat Mar 10, 2018 10:37 pm

The point is to get the right bearing crush, so where you want to be depends on the bearings.
In the past using Clevite bearings being in the middle to high end of the housing specification they listed was often good, because they usually kept the crush fit on the high end (even says so in the catalog) but that was then.....now is now.
If in doubt figure it out.

If you run too much interference fit, you start seeing the bearings folding inward near the parting lines right to begin with, and you also might THINK you have more clearance than you actually do, if you measure the bearings in the housings, because some of that is going to relax as it actually runs. You can only compress the bearings so much before they smoosh, and they may not smoosh in a healthy way or immediately, so, like many specifications, it has a happy zone and you want to stay in it.
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Re: main bolt to stud, line hone?

Post by ProPower engines » Sun Mar 11, 2018 12:11 am

Do you find it an advantage to have hot coolant in the block while using the torque plate?
[/quote]

Never tried it that way. We thought about getting the heated oil set up for the ck10 back in the days when the cup guys said it was gosphel but after seeing the system used unless you used the same type of block every time same size etc the results varied enough that we never got into it.
The part I did not like was when heating the block if left a dip in the center and they needed to be totally up to the heated temp before they would round up again and if that temp changed any the results changed a bunch as well.

When you hone a block the center of the bores grow quiet a bit from heat generated by the honing process although you would never believe it with all the oil flowing over the bores.

As for the main bores when the block heats the bore size grows some but after years of doing this the combos you produce have the clearances figured out but the hot hone deal would serve to tighten up the bores enough there could be an issue with bearings if the operator was pressed for time and had none for proper warm up causing a wiped out bearing.
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