Troubles taking a 360 .060?

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I haven't bought the crank yet, they do offer it in the 340 and the 360 main bearing diameter.
There you go. Lol good luck with the build it sounds like alot of fun. Make sure you do a thread on it.
 
with apologies to the OP, but while this is being discussed I was wondering if some of you more experienced SB engine builders could give me some info.
This is the info I was given by the previous owner about the engine in my Dart:
360 block bored .070 over (what's the bore size? Math isn't my strong suit!)
Trakers cast crank offset ground to 3.685 stroke. Stock size main journals. 2" chevy size rod journals with Eagle 6" SBC rods. I was told this equates to a 382 CI engine. What are your opinions?
 
with apologies to the OP, but while this is being discussed I was wondering if some of you more experienced SB engine builders could give me some info.
This is the info I was given by the previous owner about the engine in my Dart:
360 block bored .070 over (what's the bore size? Math isn't my strong suit!)
Trakers cast crank offset ground to 3.685 stroke. Stock size main journals. 2" chevy size rod journals with Eagle 6" SBC rods. I was told this equates to a 382 CI engine. What are your opinions?
How do you "offset" grind a crank and come up with stock sized 360 main journals?
 
How do you "offset" grind a crank and come up with stock sized 360 main journals?
It has nothing to do with the mains! The rod journal is re sized from 2.125 to 2.000, with his math that even has left an 18 thou margin to do the off-set. this has yielded a 383.54 cid size engine.
 
It has nothing to do with the mains! The rod journal is re sized from 2.125 to 2.000, with his math that even has left an 18 thou margin to do the off-set. this has yielded a 383.54 cid size engine.
Okay got mixed up there again, Thanks
 
What's the going rate for a sonic test?
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Go to eBay and buy your own Sonic tester for a hundred or $125. They're going to charge us 60 to 80 bucks at least to do it at a shop. Use your own tester then you can do all the blocks you want to.
 
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Go to eBay and buy your own Sonic tester for a hundred or $125. They're going to charge us 60 to 80 bucks at least to do it at a shop. Use your own tester then you can do all the blocks you want to.

Well that's a pretty good thought. I have not done one since college. I think I recall a minimum spec being .200" Does that sound accurate to you?
 
Well that's a pretty good thought. I have not done one since college. I think I recall a minimum spec being .200" Does that sound accurate to you?

If a shop charges $80 you can wipe your *** with the results. Cheap sonic testers are as good as experience, internet myths, and machinist’s eyes. A good certified tester, and as important a good human doing it is critical if you want a true result.

Let me ask: you got cheap pistons. You have to buy a crank, and all the other stuff, plus have it machined. How is it too expensive to spend hundreds to determine if the expense of thousands will bring success?
 
If a shop charges $80 you can wipe your *** with the results. Cheap sonic testers are as good as experience, internet myths, and machinist’s eyes. A good certified tester, and as important a good human doing it is critical if you want a true result.

Let me ask: you got cheap pistons. You have to buy a crank, and all the other stuff, plus have it machined. How is it too expensive to spend hundreds to determine if the expense of thousands will bring success?

Well, I think I would do both. When you're at a swap meet and looking at a block it might be handy to have a sonic tester to see if it would a good candidate. I not interested in buying every block I see to find a good one. I have no problem paying my machinist (Hughes Engine) to do a sonic test.

This post has nothing to do with cost but rather what have other experienced with their 360 blocks and I guess you and I would differ on the term "cheap pistons"
 
Buy “cheap pistons” meaning I’m thinking your investment in them is well under their actual cost new... as in the overall investment thus far in minimal.

You asked the cost. I own a certified tester, and know how to use it. I’ve tested for local shops before so I know what having to stand behind results can mean. Your reluctance is just a question of value to you. Is it worth it to spend 3-400 in order to make sure the other $6k delivers. Only you can determine that. Your interest in the question shows you’re asking the right questions.
That being said- you’re ignorant of a lot. That’s not a bad thing, just means there’s more to what you’re asking than what you’re asking. For instance- it won’t work on a swap meet block unless the block was just professionally cleaned, or just ran with bare iron walls. No oil, rust, dirt, or dust as all of those skew the readings. It also won’t work reliably with a cheap tester with preset frequencies. So if the tester you have can be calibrated to that particular iron (mine can) you’ll also need something to measure down to the thousandth with you too. Plus, a dependable test is not three spots on the major thrust. It takes me about 2 hrs to complete a test. 16-20 spots, plus four running scans for the thinnest in the four compass directions per hole.
 
Buy “cheap pistons” meaning I’m thinking your investment in them is well under their actual cost new... as in the overall investment thus far in minimal.

You asked the cost. I own a certified tester, and know how to use it. I’ve tested for local shops before so I know what having to stand behind results can mean. Your reluctance is just a question of value to you. Is it worth it to spend 3-400 in order to make sure the other $6k delivers. Only you can determine that. Your interest in the question shows you’re asking the right questions.
That being said- you’re ignorant of a lot. That’s not a bad thing, just means there’s more to what you’re asking than what you’re asking. For instance- it won’t work on a swap meet block unless the block was just professionally cleaned, or just ran with bare iron walls. No oil, rust, dirt, or dust as all of those skew the readings. It also won’t work reliably with a cheap tester with preset frequencies. So if the tester you have can be calibrated to that particular iron (mine can) you’ll also need something to measure down to the thousandth with you too. Plus, a dependable test is not three spots on the major thrust. It takes me about 2 hrs to complete a test. 16-20 spots, plus four running scans for the thinnest in the four compass directions per hole.

These are great points and ones I did not consider. The main take away for me is that I shouldn't rule out a 360 in my block consideration.
 
No- I wouldn’t. Btw .200” on the major thrust may be harder to come by. for a 3.79 stroke, depending on your ultimate power goal you may be able to go a bit less, like .150” minimum. Also consider sleaving, or offsetting the bore centerline as options if needed.
 
Well, I think I would do both. When you're at a swap meet and looking at a block it might be handy to have a sonic tester to see if it would a good candidate. I not interested in buying every block I see to find a good one. I have no problem paying my machinist (Hughes Engine) to do a sonic test.

This post has nothing to do with cost but rather what have other experienced with their 360 blocks and I guess you and I would differ on the term "cheap pistons"
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Get a big jar of Vaseline before you have Hughes check your block.
Have your block checked by Mulvain's he's about five miles from Hughes and charges half the price.
 
This is my 1972 360 block at 4.040 , sonic tested yesterday.
I've got some pretty good vertical scratches in a couple of bores and on the piston skirts, so I am debating taking it to 4.060.
@moper I'd be interested in your opinion on the numbers, I don't want to hijack, you can pm me if you'd rather.
I didn't get the full report yet, just a pic of the thinnest numbers from the sweeps he wrote on the block. I just wanted to give one example since there's so much rumor about the early 360's.





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How bad are the scratches? What's the power goal for it?

Ive had it at 3 different machinist's shops. Two out of three said it needs bored, the third said he would run it, if it was his. Sorry I don't have better pics of the bores or any of the piston skirts right now. The block and parts are at the shop. I also had two loose main caps that need tuned up, and getting it align honed. One issue with boring it, this shop does not have a torque plate for my block, one other does, but also has a three month backlog, not sure about the third, but they are about as far behind.

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What's your power goal?
Sorry...
I am changing cams from the Comp XE285HL hydraulic to the Hughes solid stl4650. Hoping to get around 500 with the ported heads.

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Ive had it at 3 different machinist's shops. Two out of three said it needs bored, the third said he would run it, if it was his. Sorry I don't have better pics of the bores or any of the piston skirts right now. The block and parts are at the shop. I also had two loose main caps that need tuned up, and getting it align honed. One issue with boring it, this shop does not have a torque plate for my block, one other does, but also has a three month backlog, not sure about the third, but they are about as far behind.

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Can you catch your fingernail on the scratch when you drag it across????

If you can't catch a finger nail across it, then it will be ok - run it...
 
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