RPM's & Prop

[THEFERMANATOR]

Originally Posted by Joker2

Even if my tach is not accurate shouldn't I be going 40-45 MPH at full RPM with my setup. These are the numbers I have seen with similiar setups on this forum. I am running on all cylinders I just changed a bad ignition coil, so I have been through these checks, all butterflies open, compression is 120 on 1,3,5 and 100 on 2,4,6. I guess I can try the gas in the bottle thing. Thanks

Thos numbers are not very good to see. You want to see all of them within at least 15% of each other,b ut I prefer to see them within 5% of each other myself. I would expect to see 115-125 on all 6 for a healthy engine. Try and see if you can find a shop with a dyno and see just what it's making, I think this will show you your problem and upset you at the same time. Your speed sounds correct for your RPM's with that prop, so all that leaves is the engine or lower unit.