wanting to reduce my bobweight with a longer rod and shorter piston, my 499 is 2414 bobweight with 6.76 rod

what is the longest usable rod in a 499 or 512

if my math is right a 4.25 stroke 7.100 rod should have a ch piston 1.475 at 10.7 deck height


custom rods is not out of the question how long of rod will fit

Most people use the Chevy 7.10 rod but the 7.250 rod will also fit just fine. You'll probably need a semi-custom piston with the 7.250 rod. There are shelf pistons that work with the 7.10 rod.

I went with a 6.8 GRP alum rod on a 514... with CP pistons
for a light weight package(was going to turn it 9000+)
with B1M/C heads

Which rod journal size and stroke are you wanting the rods for? I like and use the longest rods I can use in any Mopar B, RB and Hemi strokers motors I build

Is this setup for a stock block? I run a center counter weighted crank with the express purpose of reducing cap walk and stress on the block. It worked on my mega block and I am sure it would help a lot to reduce stress on a stock block too. If you want to get the lightest combo, you can go down to a 2.100 chevy small block bearing for an even lighter set up. That would require a custom aluminum rod I believe, but you could go as long as you like. A piston with a 1.200 compression height would need a rod 7.375 long and the whole deal would be VERY light! Nascar and Pro Stock run smaller bearings than that, but you probably want to have better service life than they require.
I mention a 1.200 compression height because piston stability might become a problem with a shorter piston. But you can go as short on compression height as the piston maker says will work well, and then custom make the rods to fit. Their are shelf stock 1.12 pistons out there, which would need a rod that is about 7.455 long. The limiting factor is piston compression height.

gregsdart, thanks for the info. Now i have more questions than i had. lol

yes this is for a stock block

i am thinking the only way to get 2.100 crank throw is to turn down a 2.200?

will a 2.100 rod bearings last 300 7,000 rpm 1/8 mile laps?

7.3 or 7.4 rod length is that a real choice, no clearance issues or durability problems?

i'm with you on 1.20 ch being a little more stable than the 1.12

what is the life limit on these new aluminum rods?

My info on the 2.100 bearing crank comes from Crower, plus previous builds. I have run 7.1 x 2.100 bearing aluminum rods. The crank with a 2.100 journal will last a long time according to Crower. Same with the rods. On the crank, you can order one built, or offset grind a 2.2 or even a 2.375 crank provided you have a knowledgeable machinist elongate the oil holes to position them on the rod journals after the regrind. There will be no clearance problems with the rods until the stroke gets very long, (except bore notching) like 4 .75 inch or more.