Had the boat @ Paris this friday and @ WOT top speed was only 49.7 mph @ 3000 rpm. I'm sure this motor should rev a lot higher. What is it? ignition is MSD with MDS Distributor, Holly 750 Double pumper, Holly fuel pump. It runs good just think it has more in it. 49.7 mph is cool with me but a little more couldn't hurt. Any ideas would help. I am going to check throttle linkage to be sure the pedal is allowing WOT on the carb. other than that not sure what to check

I learned something today. The tach was set wrong. it was set @ 4=12 pail what ever that is now i got it on 3=8 cyl. That 49 mph was with 4 guys on the boat with full gas tanks and full ice chest. I think thats ok with me for now. it is a 21' open bow. Is that slow for a big block boat loaded? It jumps out of the water pretty quick so with the tach reading wrong that must be the speed. The GPS don't lie.

Was that gps or water speedo?  My 23' ran in the 50's with 4 people ice chest etc, when it was stock.

Oh, that was a Ford engine     

I would think it should go quicker than 49 with a 21" boat.  With a water speedo you're just
taking a good guess anyway.