Ported 6400?

[computeruser]

For folks who have done this or have run one, what kind of power can be had out of a ported 6400? How would it compare to stock power out of a 7900 p/c? What other saws would a ported 6400 be similar to in performance and feel?

I remember years back when this platform was new that Big Dave got good gains on the 6400, and that others have done so since that time, too. I have a couple new 6400s sitting around in boxes, but only one OEM 7900 p/c left, so this idea is kinda intriguing.

Any thoughts or experiences you'd like to share in this topic would be welcome.

 

[CR888]

Biggest issue for me with the 6400 cylinder is its open port design. Not that this means it can't be ported for increased performance but I'd take a closed quad over it any day. I have a spare 6400 cylinder I'd like to port, so I am subbed & interested in hearing others ideas on porting them. Randy mentioned they can be ported with success.

 

[Chainsaw Jim]

Open port doesn't mean less in performance. This has been a silly ongoing rumor.
One of the most legendary saws ever made and still highly popular to this day is an open port design.

 

[Onan18]

Open port doesn't mean less in performance. This has been a silly ongoing rumor.
One of the most legendary saws ever made and still highly popular to this day is an open port design.

MS200T?

 

[Chainsaw Jim]

MS200T?

That would be correct.
I built an open port ms180 that smokes a 200t.

 

[Savage Saws]

Open dual port 020t. This my personal climbing saw and still has a hint of 4 stroke at 16,300rpm.

 

[Poleman]

A ported 6400 in my opinion is around a 372 as its stronger than a 365. With carb work and unlimited coil IT'S A REAL SLEEPER!
I've put a 665 Solo top end on a 6400 to try the close port effect...it's a winner! I know there's more in it by the way it runs now (mild porting).

The 6400 has its place for medium size work but is not a 7900/7910. None the less it's a GREAT saw!