I'm building a new engine and just realized my last bridgeport did not have the rotor housing notch. It is a standard bridgeport and made 217WHP @ 8100 rpm.

1. Can someone please confirm that the "notch" in the rotor housing can be used with a standard bridgeport and does not effect the water jacket.

2. How much change in WHP do you think this will make? Maybe 240WHP @ 8500 rpm?

3. Does the "notch" in the rotor housing just expose more of the "eye lid" port or does it also allow the port to open earlier and close later. I'm guessing it affects both volume and duration.

Thanks

 

Never mind, now it turns out the motor does have it.
Another question: how advanced should the timing be?

1. 20-24 degrees for bridgeport?

2. If I advance to far with carbon seals while tuning, will it detonate and blow the new seals/motor?

3. I believe my old motor was running +20, it still made more power as we advanced to +22 but didn't want to risk anything.

4. Currently running about 93 Octane with small amount of 2 stroke oil.

5. What Octane should I run if I do advance the timing further?
Thanks

 

1. sure, ive seen as much as 27, but it depends on the port, intake and exhaust

2. i'm thinking with an NA that it would be hard to do, but everyone else seems paranoid about that.

3. ok

4. 93 is high, but its probably safer/more stable

5. i wouldnt change the octane

 

Thanks for the info, the tuning shop works with a lot of turbo rotaries. May cause them to be extra cautious.