Electric conversion of 20' Malibu Euro f3

[sfriedri]

Thought I would join the forum and post on my newest EV conversion project. This is my third major EV conversion, having also done an ATV and my award winning 68 Mustang.

I have a 1991 20' Malibu Euro f3 ski/wakeboard direct drive boat that was powered by a 5.7L V8. It is now fully electric and has been in the water for most of the summer. Some basic specs:
- 85kWh battery pack (16 modules from a salvage Tesla Model S)
- 300HP / 515 ft-lbs torque UQM motor and controller
- Closed loop glycol cooling systems for motor/inverter and batteries
- 6.6 kW EVSE compatible charging
- Weight about 200lbs heavier than stock

The power/torque is obviously much higher than the original V8, so the hole shot is very fast. Boat range is about 45km when running on plane at ~40km/hr. Last few times out on the water with my sons wakeboarding / skiing only used about half of the battery charge, so seems to be plenty of range for our regular outings. My son was out on the boat yesterday with 7 other friends wakeboarding and tubing and that was the first time we used a full charge, but even with a heavy loaded boat they were still all able to have a full afternoon of fun.

A few photos below. Happy to entertain questions/comments!

 

[airshot]

Very interesting.....estimated cost in comparison to the gas engine ??

 

[sfriedri]

Very interesting.....estimated cost in comparison to the gas engine ??

I looked up prices for a new inboard engine/trans and a 300HP outboard since I didn't know what they cost. Looks like I spent more than a new inboard engine but less than a new outboard. Of course that doesn't count my time, but I enjoy these projects.

 

[Chris1956]

What is charge time for that battery pack?

According to your estimates, max range is 28 mi for those of us in the US, and speed is 25MPH. The range may be inadequate for skiing, and speed is too low for slalom skiing, which is what the boat is designed for.

is there a practical way to get 35MPH out of it?

 

[sfriedri]

What is charge time for that battery pack?

According to your estimates, max range is 28 mi for those of us in the US, and speed is 25MPH. The range may be inadequate for skiing, and speed is too low for slalom skiing, which is what the boat is designed for.

is there a practical way to get 35MPH out of it?

Top speed after the conversion is just under 50mph, with a 13x13 prop. Like most ski boats, the speed is prop limited rather than power limited. Besides, like most EVs, power is not an issue and it has more than the original V8.

I am by no means a pro water skier, but have been slalom skiing for 40+ years, and we have our own slalom course set up on the bay we live on. Even before the conversion, this boat didn't throw a really friendly wake for slalom skiing. It is more of an all-around boat good for having fun rather than setting slalom records. My brother has a Mastercraft prostar that has a much nicer wake.

As I mentioned in the original post, the boat has plenty of range for our needs. Going out with three skiers/wakeboarders for a session only uses about half a charge and is easily charged back to full before the next time we want to go out.

 

[airshot]

Top speed after the conversion is just under 50mph, with a 13x13 prop. Like most ski boats, the speed is prop limited rather than power limited. Besides, like most EVs, power is not an issue and it has more than the original V8.

I am by no means a pro water skier, but have been slalom skiing for 40+ years, and we have our own slalom course set up on the bay we live on. Even before the conversion, this boat didn't throw a really friendly wake for slalom skiing. It is more of an all-around boat good for having fun rather than setting slalom records. My brother has a Mastercraft prostar that has a much nicer wake.

As I mentioned in the original post, the boat has plenty of range for our needs. Going out with three skiers/wakeboarders for a session only uses about half a charge and is easily charged back to full before the next time we want to go out.

Sounds pretty cool, would like to see pics or videos of it performing !!!