Bb chevy rod width at the big end

[Jeff M.]

What is the width of a stock bb connecting rod. All of the aftermarket are .990 to .992. What about the journal width. Not talking about diameter. I am trying to figure out why I have .032-.034 connecting rod side clearance with my NOS ls7 crank. Car is a 71 ls6. Any opinions, as the gm spec is .015-.025

[Clem Z.]

Re: Bb chevy rod width at the big end

What is the width of a stock bb connecting rod. All of the aftermarket are .990 to .992. What about the journal width. Not talking about diameter. I am trying to figure out why I have .032-.034 connecting rod side clearance with my NOS ls7 crank. Car is a 71 ls6. Any opinions, as the gm spec is .015-.025

check the width of the crank journal as it should be 2.000" having too much clearance is not a problem as not having not enough would be

[Joe L.]

Re: Bb chevy rod width at the big end

check the width of the crank journal as it should be 2.000" having too much clearance is not a problem as not having not enough would be

clem-----


I have the crankpin spec at 2.005"-2.009".

[Joe L.]

Re: Bb chevy rod width at the big end

What is the width of a stock bb connecting rod. All of the aftermarket are .990 to .992. What about the journal width. Not talking about diameter. I am trying to figure out why I have .032-.034 connecting rod side clearance with my NOS ls7 crank. Car is a 71 ls6. Any opinions, as the gm spec is .015-.025

Jeff-----

I don't have a big block rod that's handy enough for me to get at right now. However, I have the crankpin spec at 2.005"-2.009". With that spec at the upper limit and a rod at the low end of what you've apparently measured (0.990") you should have a clearance of 0.029" which is just outside the GM upper limit and as clem mentioned should really cause no problem.

To get the kind of clearance that you measured with the rods at the width dimension you measured the crankpins would have to be out-of-spec at the high end. So, I would suggest you measure your crankpins.