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3/8 coarse threads are standard on SBC's
 

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If you're doing a sbc 3/8 coarse is what you're looking for. However, the length depends on how long the slots on your stand are. The rule of thumb is you want the threads inside block at least 3/4" each. So measure before you buy them.
 

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3/8 coarse = 3/8X16 in technical terms if you need that info. Most bolt bins use the threads per inch term at stores here. You could buy 3 inch bolts and use a washer or two if they bottom out. Any grade will work but if you want go with a grade 5 or 8 if it makes you feel better. The bolt is 3/8 dia so any thread engagement past that is not going to make the bolt any stronger but helps the block from stripping out. JMO, RM
 

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Beware of bolts that are not graded or less than grade 5. Common at home improvement stores and some hardware stores is ungraded and grade 2. These can break with your hands and can kill you if you are not careful!!!:mad:
 

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You have to be careful how much weight you put on your engine stand.

A typical full dressed all iron small block Chevy weighs about 600#.

A typical cheap engine stand from Harbor Freight is rated at 1000#.

A typical grade 2 bolt will support 3332# at 75% yield strength. If you use 4 of these bolts, the load rating would be 13,330#.

If you step up to Grade 5 bolts, the load per bolt increases to 5347#, or 21,390# for a set of 4.

If you're really squeamish and opt for the Grade 8 bolts, you're looking at 7595# per bolt, 30,380# for a set of 4.

I'll bet there are many weaker points in your mounting system. Many failures are caused by overtorquing the bolts, which puts tremendous stress on them.
 

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Got it mounted just fine and finally I can start to work on the engine. Got some 3" grade 8s but should have probably gone with 2.5 or 2.75. Oh well just used some washers as spacers. Any way I can't wait to get started.
 

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Engine stand location?

Hi! Where do I bolt the engine stand into the engine?

I'm guess it goes where the transmission bolts onto, but I don't want to guess.

I don't have the transmission / engine block bolts, so I'll have to go find some that fit... (If, that is where it really does bolt onto. )
 

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Not a chevy engine but this help?

 

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Hi Al,
What kind of engine is that?
I was waiting on this question.

It's a Twin Turbo Mitsubishi V6 2.8L for a GT Rally car. Has dual overhead cams.

This was a practice engine that they ask me to check bearing. With the amount of boost and abuse it eats bearing and cranks. This one need a crank and bearings.

I was just amazed at how HD the crank and block area. everything was HD and precision fit.

Felt bad bolting it to a 75.00 engine stand.:eek:

AL
 

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Engine block / transmission bolts

What size bolts do I need to go from my 350 block to my transmission? I'm trying to mount my engine on a stand, but I don't have these bolts...:rolleyes:

Do you need to know anything specific about my engine? If not, can I please get some measurements? Thank you.:)
 

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I merged these FIVE posts into one. This is now an official FAQ.
 

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Grade 2 bolts are rated at 43,000 psi @ 75% yeild strength
Grade 5 bolts are rated at 69,000 psi @ 75% yield strength
Grade 8 bolts are rated at 98,000 psi @ 75% yield strength
The root diameter of a 3/8-16 bolt is 0.294", providing an area of .0679 square inches.

Grade 2 3/8-16 bolts would be rated at 2919# each @ 75% yield strength for a total of 11,676# for four of them.
Grade 5 3/8-16 bolts would be rated at 4684# each @ 75% yeild strength for a total of 18,376# for four of them.
Grade 8 3/8-16 bolts would be rated at 6653# each @ 75% yeild strength for a total of 26,612# for four of them.

I have yet to have an engine that weighs even 10% of the lowest figure. My concern would be on the welded tube that holds the head.
Hi Mike,

I agree with you that the stand welds are probably the weakest point, but dont you think the length of the weight supported by the bolts would be an important park of a calculation on bolt load?
 

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An engine is a pretty regular shaped piece, so it is relatively easy to calculate the stress on the bolts. The stress that is on the engine bolts is also on the arms, the bolts holding the arms to the head, and it is all concentrated on the junction of the head and the tube.
 

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Ahh, nevermind my last question.

I eyeballed it, and it took three trips to my hardware store, harrassing the kind old folks that helped me out to get them.

Oh, and sorry about not searching more before i posted.:shh:
 
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