Bobweight questions

[ckessel]

Just for my own curiosity, do any of you know the Bobweights of a stock 383 Magnum and a 440 Magnum? Both 68-70 vintage?

 

[Rishi]

I think it can be as high as 2900 on the OEM 440 HP engine with six pack rods.

 

[polyjohn]

I can calculate the 440 Magnum for 1969 for you.
I can also do the 440 six-pack for 1970 as well.

Best wishes from John

 

[ckessel]

Thank you both. I'm just wanting to see what the difference in the oe stuff is compared to the stroker packages. More stuff for my gearhead brain to stew on.

 

[Rishi]

Changing rods and pistons from OEM can drop it 1000g easy.

 

[BSB67]

Factory 440 with LY rods is about 2750 gr. 4.25 stroker in a 440 block about 2250 gr.

 

[RemCharger]

Here's one with icon pistons

 

[dvw]

The lightest I've run with 4.500" bore, 7.100" steel rod has been 2222 grams. Currently 2360 grams with a thicker pin and slightly heavier piston. Rings make a difference. one complete cylinder set of .9mm were 25 grams lighter than a comparable .0430"
Doug

 

[BSB67]

…..and, the 5/64” ring is about 11 gr. heavier than 1/16” rings

 

[Diodedog]

I just balanced a stock piston 383, Bob was 2460 and a 440 with 2295s using stock pins so very close to stock, Bob was 2580ish, might be off a hair but the notes are in my shop, I'll check it tomorrow.