BBC 565 Bore and Stroke

[Mark @ Meridian Tool]

I'm about to purchase the rotating kit for a BBC 565.
It will be a 4.600" bore Dart Big M 9.8 deck, with Dart CNC 355 heads w/110 chambers.
I'd like to hear some educated opinions 4.25" stroke with 6.385" rod vs.
4.25" stroke with 6.535" rod, and the rq'd comp heights/ring packs
for these packages. Any pro's and con's to either set up?
This engine may see as much as a 400 h.p. shot in the future.

[NOS-Nelson]

4.250 stroke and 6.385 rod will give you a 1.27 CH with the piston .020 in the hole. If you use an .043 upper Hellfire you can get the top ring down .350. The 6.535 rod works with a 3.950 stroke and the same piston.:cool:

This is for a 9.800 block I assume?

[68Bird]

Wouldn't the 4.375 stroke be a 582? Sorry if I'm stating the obvious but you said you wanted a 565.

Craig

[Mark @ Meridian Tool]

Wouldn't the 4.375 stroke be a 582? Sorry if I'm stating the obvious but you said you wanted a 565.

Craig

Oops! You're right. The point of the question is the different rod lengths and
comp heights. Original question edited!

[NOS-Nelson]

Oops! You're right. The point of the question is the different rod lengths and
comp heights. Original question edited!

N/A = Long Rod, Nitrous = Short Rod.:cool:

[Mark @ Meridian Tool]

My decision just got very easy.
I just bought a lightly used Callies Pro Magnum 4.25" , 6.535" Oliver I beams,
Je 4.6" piston set , and ATI balancer for less than an Eagle rotating kit ($1600).
This should be a slight step up from my current 431" BBC. LOL.:p
Time to hit the machine shop!

[NOS-Nelson]

My decision just got very easy.
I just bought a lightly used Callies Pro Magnum 4.25" , 6.535" Oliver I beams,
Je 4.6" piston set , and ATI balancer for less than an Eagle rotating kit ($1600).
This should be a slight step up from my current 431" BBC. LOL.:p
Time to hit the machine shop!

That's a good deal but I wouldn't spray it.

[Mark @ Meridian Tool]

That's a good deal but I wouldn't spray it.

Honestly, I think that would be well down the road for me. This thing could go
high 9.20's n/a. That's considerably quicker than I've ever been. I'll be spending
the off season on safety and brake system upgrades.:)
When you say you wouldn't spray it , you mean within limits, or whatsoever?

[NOS-Nelson]

Honestly, I think that would be well down the road for me. This thing could go
high 9.20's n/a. That's considerably quicker than I've ever been. I'll be spending
the off season on safety and brake system upgrades.:)
When you say you wouldn't spray it , you mean within limits, or whatsoever?

With that combo you are running roughly the same CH as a 632. It all depends on if the top of the oil ring land is zeroed with the top of the pin. Even then the top ring is still going to be higher on the piston than desireable. I've done it myself but you have zero room for error.