71' 350 Questions

[Southern Shaker]

So i picked up this 73' cheyenne super friday and took a look at the motor before i made my run this weekend its a small blo9ck 350, had my uncle get me some info on it. well he called me today an told me the Guy that was Building the truck pulled the engine from a wreck 71 squad car he used to have in his junk yard. the motor is "Supposably supposed to run Strong but who know . Now what i would like to know is , Is there anyway to find out if its a 4 bolt main by Any of the numbers on it? i know i could pull the pan . But i just thought id ask this question first?

[TBONE1964]

As far as I know the only way to know for sure is pull the pan. The "010" casting number will not tell you.

[Southern Shaker]

Haha dang i was hopin there might have been an easyer way , Trucks Lowered a bit an im on the larger side of life haha oh well on the lift it goes i guess

[slow-1]

On the drivers side of the block on the rear "ledge", where the transmission mates, there is a casting #, you may find out with that number.

[Ol Blue K20]

Usually a four bolt will have the 010 number and a oil galley plug above the timing chain cover
Posted via Mobile Device

[cdowns]

4 bolt main engines are aboout the most foolishly overrated things by dweebs ever

[jjzepplin]

If it's a 2 bolt main and runs good, Why take it apart? Who cares as long as it runs? Built correctly they are very comparable. I've never seen a main break. Bearings go bad yes.

[TBONE1964]

As a professional engine builder for 15 years of my life, I will again say that the "3970010" casting number does not designate a 4 bolt main block, it does not even mean 350. Yes it is likely a 350 but could also be a 327. I want to clear that up for anyone who may have questions concerning that casting number.

Attached is a casting number guide for blocks and cylinder heads.

As far as strength of the block, unless you are zinging the thing over 14,000 RPM's you really will see no benefit from using a 4 bolt main block.

http://www.thedirtforum.com/castings.htm

[LONGHAIR]

Originally Posted by TBONE1964

As far as strength of the block, unless you are zinging the thing over 14,000 RPM's you really will see no benefit from using a 4 bolt main block.

This ^^^ is just a more tactful way to say this......

Originally Posted by cdowns

4 bolt main engines are about the most foolishly overrated things by dweebs ever

Agreed either way

[slow-1]

Originally Posted by TBONE1964

As a professional engine builder for 15 years of my life, I will again say that the "3970010" casting number does not designate a 4 bolt main block, it does not even mean 350. Yes it is likely a 350 but could also be a 327. I want to clear that up for anyone who may have questions concerning that casting number.

Attached is a casting number guide for blocks and cylinder heads.

As far as strength of the block, unless you are zinging the thing over 14,000 RPM's you really will see no benefit from using a 4 bolt main block.

http://www.thedirtforum.com/castings.htm

As an amatuer engine builder of 30 years, I completely agree with both of your points.