rods

Windedv6

Ty n 10s
Re: rods

We use 5.7 rods on the 3.75 crank. The 5.85 and the 6s will give you less compression height on the piston (because of the piston dish), if you want to stay with an 8.5:1 - 9.5:1 compression ratio. If you are doing flat top pistons then go with 5.85 rods, but your compression ratio will be in the 10:1 range or higher depending on the head chamber size. Cometic makes a .051 (vs .040) which will help some to keep the compression down.

John
 

sean

Member
Re: rods

We use 5.7 rods on the 3.75 crank. The 5.85 and the 6s will give you less compression height on the piston (because of the piston dish), if you want to stay with an 8.5:1 - 9.5:1 compression ratio. If you are doing flat top pistons then go with 5.85 rods, but your compression ratio will be in the 10:1 range or higher depending on the head chamber size. Cometic makes a .051 (vs .040) which will help some to keep the compression down.

John

i should have explain myself better, it's a bow tie block 051, fully ported polish brodix pontiacs, billet steel 3.75 stroke crank, twin turbo, if have to i would get custom je piston's, the machine person that i was using that was going to built it for me just past away and i had to get my stuff back. i talk to a known builder in new york and he told me to go with 6'' rods.i thought that was to big that is why i'm asking on here.
 
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5678TA

New member
Re: rods

from what i understand, shorter rods are better for lower rpm (<6000) and smaller heads. longer rods for higher rpm (>6000).
 

sean

Member
Re: rods

We use 5.7 rods on the 3.75 crank. The 5.85 and the 6s will give you less compression height on the piston (because of the piston dish), if you want to stay with an 8.5:1 - 9.5:1 compression ratio. If you are doing flat top pistons then go with 5.85 rods, but your compression ratio will be in the 10:1 range or higher depending on the head chamber size. Cometic makes a .051 (vs .040) which will help some to keep the compression down.

John

if i used a 5.7 rod won't that make a top heavy piston? i have the bow tie 051 block deck height is 9.025. with billet 3.75 stroker, I'm aiming to a 9:1 i was unable to get this far with my builder as, he gotten sick and past away. i just got my stuff back. r.i.p Don!!!! also i'm going for street strip set up
 

sean

Member
Re: rods

if i used a 5.7 rod won't that make a top heavy piston? i have the bow tie 051 block deck height is 9.025. with billet 3.75 stroker, I'm aiming to a 9:1 i was unable to get this far with my builder as, he gotten sick and past away. i just got my stuff back. r.i.p Don!!!! also i'm going for street strip set up

ttt
 
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