Drill bit test rehash
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From: Pittsburgh
Drill bit test rehash
Allright, I have my 390 more or less torn torn so I figured while I had it apart i'd do the drill bit test just to see what I was working with. I got myself some measurements, but then was presented with an issue.
I searched for the drill bit test on this forum, but all of the posts i found said "do a search for drill bit test, it's on here somewhere".
So I have a set of numbers, but nothing to compare them with.
So first off, I would like to request that the "drill bit test" measurements be added to the FE FAQ and secondly could someone just tell me what my numbers mean?
I pulled out an assortment of drill bits and allen wrenches to do my test to find out what the best fot was. The biggest one that would fit anywhere wound up being a 3/16 allen key across opposite points. It measures to .2165" which is bigger than 13/64 of an inch but smaller than 7/32.
Justin
I searched for the drill bit test on this forum, but all of the posts i found said "do a search for drill bit test, it's on here somewhere".
So I have a set of numbers, but nothing to compare them with.
So first off, I would like to request that the "drill bit test" measurements be added to the FE FAQ and secondly could someone just tell me what my numbers mean?
I pulled out an assortment of drill bits and allen wrenches to do my test to find out what the best fot was. The biggest one that would fit anywhere wound up being a 3/16 allen key across opposite points. It measures to .2165" which is bigger than 13/64 of an inch but smaller than 7/32.
Justin
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From: CT
Drill bit test is Dave Shoes invention. 64ths are use as a universal measurements.
352, 360, 390, 410 blocks use a 16 to 17/64" drill bit shank.
428 and some 361,391 and 406 blocks 13 to 14/64" bit shank.
Some 406 (with 427 wall cores) and most 427's a 8/64" bit shank.
While it's a good field test it still needs to be conclusive with an accurate sonic map. The drill bit test just tells you what cyl wall cores the block was cast with. Not how thick they are. But still a nice thing to know when block shopping.
I'd also seek Dave's permission and credit him in the writeup if this was to become a fixture in the FAQ section. He's a good guy and deserves the credit due.
352, 360, 390, 410 blocks use a 16 to 17/64" drill bit shank.
428 and some 361,391 and 406 blocks 13 to 14/64" bit shank.
Some 406 (with 427 wall cores) and most 427's a 8/64" bit shank.
While it's a good field test it still needs to be conclusive with an accurate sonic map. The drill bit test just tells you what cyl wall cores the block was cast with. Not how thick they are. But still a nice thing to know when block shopping.
I'd also seek Dave's permission and credit him in the writeup if this was to become a fixture in the FAQ section. He's a good guy and deserves the credit due.
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From: Pittsburgh
so i have the 428/406 cores. nifty.
And i know it's not 100% accurate, but what's the sense in even getting the block sonic mapped for 428 bores if it's a plain 390 block.
Justin
And i know it's not 100% accurate, but what's the sense in even getting the block sonic mapped for 428 bores if it's a plain 390 block.
Justin
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From: idaho
well, if you pop out the center freeze plug on either side, then you can place the drill bit shank in between the cylinder walls of the center two. you use the bit as a gauge, asuming the cylinders are all located the same, which they should be, then you can tell if the block was cast with thicker walls.
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From: Pittsburgh
The smaller the drill bit that you can fit between the cylinder walls, the thicker the walls are and the more overbore it ::SHOULD:: be able to take.
Justin
Justin
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Originally Posted by FFR428
I'd also seek Dave's permission and credit him in the writeup if this was to become a fixture in the FAQ section. He's a good guy and deserves the credit due.
It's in a place that's off-limits to me, and above all, it's an old OLD link that is being (or should be) fazed out over time. The right thing to do would be to make a tech article out of the FAQ and add the drill-bit test, or at least, a link to this thread.I'll put it on my to-do list
For the time being, this thread will BE the post that comes up when you search for "drill bit test" in the FE forum.
If you click on Search above, go to Advanced Search, and put in "+drill +bit +test" and select Search Titles Only, and select the FE forum.
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