1BIGJIM

Buying Monday morning and need to make a choice!
4.25 stroke
I can find the exact pistion if I use a 6.135 rod
or
I have to have one milled to lower the compressiong ratio if I use the 6.385 rod.

What would you recommend?
Anyone using a 6.135 rod?
Any ideas would help.
THanks
JIM

88Fountain

I use a 6.385 rod in my 540's. I ended up buying a kit from World Products, part #108150. It uses a "H" beam rod, haven't had any problems yet. The pistons are Mahle Motorsports pistons that are coated. The use of the longer rod with the longer stroke is better geometry.
Aaron

WETTE VETTE

6.385 will be a better rod/stroke ratio. If you are going with a new rotating assy the costs should be the same. I ran some off the shelf pistons (SRP) and a 6.385 rod in my 4.25" stroke 496.

Mr Gadgets

BigJim,
go get the june issue of Hot Rod. They did a huge test on different combinations. Came up with some real thought provoking info. I have 8" rods in my motor.. seems it doesnt make more power.. but when I toss a new 5" crank at it, it may..
I found the article very interesting.. good luck!

articfriends

8" Rods???What kinda deck height ?

Mr Gadgets

11.665" way out of porportion to the real world for sure.

BigJim,
another thing to consider.. if you have to go with a custom made piston, I know JE will require at least 4 new ones to be made if you need to replace one. When I order a custom piston, I usually get two extras, for that just in case senario. But if you can get off the shelf piston's life is easier. You may be able to get a shelf piston and then have the local machine shop mill them, that is if you trust the machine shop. I trust JE and let them do it all.

I hope that helps with your decision. Reading that article will tell you that rod length doenst do much for power, but might help with wear. How much?? That is debateable.. Good luck
Dick