Dolmar 64xx/73xx/79xx series, smurfs and solo 665/675/681 thread

[kingOFgEEEks]

Do you have a picture of the chunk out of the exhaust port?

Depending on how bad it is, it might be a good candidate for a 681 stroker with the base and squish cut, and through raising the exhaust accordingly it might get cut out.

It's taking a bath in the USC right now. I'll snag a pic when it comes out.

 

[MustangMike]

From what I understand, the top of the exhaust port is not as critical as the bottom, so after cleaning it up and smoothing any boogers, you might have a good backup!

I disagree; the port opens from the top. Unless you want to change the port timing, it is critical. It can be restored if you cut the base or build w/o a base gasket, but the rest of the ports would have to be modified. It is always important to have a little curve on the ports and proper beveling to help prevent ring hang ups. That said, if the ring broke first, nothing would help.

Sending it to a porter that can do all these things (including moving the other ports, if necessary) would likely be a wise choice, and then you would have a ported saw!

 

[kingOFgEEEks]

It’s pretty ugly.
Intake side:
Exhaust:


There’s a big chunk of plating missing below the exhaust port, as well as the damage above.

 

[hacskaroly]

I disagree; the port opens from the top. Unless you want to change the port timing, it is critical.

Good to know, I learned something!!

 

[Powerstroke Cowboy]

It’s pretty ugly.
Intake side: View attachment 447903
Exhaust:
View attachment 447904

There’s a big chunk of plating missing below the exhaust port, as well as the damage above.

Thanks for the pictures. The exhaust is worse than I thought it might be.

As long as the plating does not keep peeling it could be made to work again.

Looks like a good cylinder to try an extreme base a squish cut with a stroker crank and see what happens. Might be able to make a hot saw out of it.