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For me the T750 season was a refresher course in trying to get a boat competitive one step at a time.
I had to keep reminding myself not to assume too much and to stay with the plan.
The Plan
[1] concentrate on the boat’s handling on the race course first.
[2] leave the motor improvements as the last and final step.
[3] keep the motor consistent race after race. Don’t mess with it.
[4] make one small change at a time.
[5] only use testing as a ball park. Judge results on the race course.
[6] work on prop set up. Use different props and different engine heights.
[7] focus on elapse times not speeds
[a] how fast is it in and thru and especially out the corner? EXIT SPEED!
[b] how far down the straight did it take to get to top speed
[c] what was the lap time
[8] Where does the competition have the advantage?
[a] are we keeping ahead thru the turn.
[b] where on the straightaway do they catch us?
[c] what is their exit speed compared to us?
[d] does their boat handle better?
[9] how does the boat feel to the driver?
[a] stable, comfortable, lazy
[10] don’t keep changing a number of things at the same race. One change at a time each day.[b]
[/b]
Now here are the results

NO test time prior to Waterford! That is not a good way to start the season.

Result: boat got lapped in each race. Poor handling, boat would not set for the turns, Only positive was the boat was only 3 to 5 miles off speed wise. But no where close to being competitive.

Tested prior to Gravenhurst different props, different engine heights Handling improved, but no speed increase.

Result: Handled better Saturday than Waterford. Still off the pace speed wise, but was more competitive. Made engine adjustment Saturday after races. Sunday race was better. Good speed in the corners and running middle of the pack.

Tested several props prior to Dunnville. None of the props had any speed advantage. Motor is too tired to make any difference. Two props handled better in the turns.

Results: Dunnville ran the first prop. Not too bad. Overall boat could run with Jeremy. They were close to equal.
Sunday ran what we think was the best prop. This race may have been poor for the fans, but thanks to Jeremy and Thom we gained a lot of information.
Jeremy and Thom LET Jim get a head start. The plan was to have both Jeremy and Thom catch and pass Jim. The boat ran much better with this prop and having the lead and the good water helped.
Result: Jeremy couldn’t pass us. His speed advantage was about 2 mph and that was right at the end of the straights. No difference anywhere else.
Thom had superior exit speed and more top end. When Thom and Jim were side by side middle way thru the turn. Thom can accelerate faster.
Thom’s boat looks so much faster because:
[1] he accelerates faster from 45 mph to 54 mph compared to us. So he is already passing us early on the straight.
[2] he has a top speed of 57 to 59 mph. Just my guess. So he pulls all the way down the straight. Excellent race boat!

Next steps:
[1] the fresh motor will improve our acceleration. We should be able to stay with him until 55 mph.
[2] then we will see where his top speed comes into play.
[3] with a good start can he catch us? We will know next year at Waterford.

PS The four stroke 60 hp 15 inch motor is in my truck to-day. I loaned Mark a prop to try on their Tuff 16. We should get feedback later and this will help us prop the T750 4 stroke next spring.

Excellent tips for ALL Performance boaters. Thx Don

Neato! When is waterford??

Jake, some for the info I got to-day from Mark is the same information I got from fellows running in Europe. The gear case is a 1:84 ratio. The early model had a 1:64 ratio. Mercury changed it because the motor was lazy out of the turns. That is the same problem you had with Fraser's twin carb 60 hp 2 stroke Mercury. Mark had not tried a large diameter prop.
The gear case looks like it could run close to 13 inch diameter. After their prop shaft broke, they lost their good prop. They have been trying a few loaner props. With an 11 x 20 they get good punch to 55 mph. They have run over 60 mph on a good run. Their Tuff 16 has run 64 mph with the prop they lost. With a 1.84 ratio and a rev limited at 6300 rpm, That is impressive. I hope to 57 to 60 mph on the race course. That put us in the game with Thom, Craig and you. I have 5 props now that can run those numbers based on the math. I will likely need a few races to find out which one is the quickest.
Jim doesn't like the toaster being so quiet. Now there will be two quiet ones.