FSH 210 Sport
Jetboaters Admiral
- Messages
- 6,706
- Reaction score
- 7,946
- Points
- 472
- Location
- Tranquility Base
- Boat Make
- Yamaha
- Year
- 2020
- Boat Model
- FSH Sport
- Boat Length
- 21
Thanks!
Your density altitude was 2878’. I had to make some assumptions since I didn’t know the other parameters of altimeter and dew point. I don’t have a good feel for a SC engine and how it would be affected by that 2900’ elevation but I’m sure there is some affect, maybe 5% or 25 hp loss.
![182BD995-5E3E-4444-B317-04B5DFD475E2.jpeg 182BD995-5E3E-4444-B317-04B5DFD475E2.jpeg](https://jetboaters.nyc3.digitaloceanspaces.com/data/attachments/225/225563-3520b523f58f8173cff4b3fe82de228a.jpg?hash=bF4oi9vEcf)
I don’t know the conditions when you tested the oem impellers.
I’m assuming you already have the 12/18’s, if not you could have Dave at leading edge take some pitch out of the ones you have, much less $$$ to do it that way.
If it was me, I’d try the 12/18’s or repitched first and see what rpms and performance you get out of those. I’m sure you will gain rpms, it will be interesting to see if the 12/18’s get you back up to the oem impeller rpms range / speed or closer to the rated max rpm of 8000 and should get you back up to the oem top speed?
If I remember correctly, the tuner will only give about 5 hp at the stock rev limit of 8000 rpm, raising the rev limit to 8500 is where the 25 hp gain would be seen, but that requires a lower pitch impeller to get that many rpm.
Your density altitude was 2878’. I had to make some assumptions since I didn’t know the other parameters of altimeter and dew point. I don’t have a good feel for a SC engine and how it would be affected by that 2900’ elevation but I’m sure there is some affect, maybe 5% or 25 hp loss.
![182BD995-5E3E-4444-B317-04B5DFD475E2.jpeg 182BD995-5E3E-4444-B317-04B5DFD475E2.jpeg](https://jetboaters.nyc3.digitaloceanspaces.com/data/attachments/225/225563-3520b523f58f8173cff4b3fe82de228a.jpg?hash=bF4oi9vEcf)
I don’t know the conditions when you tested the oem impellers.
I’m assuming you already have the 12/18’s, if not you could have Dave at leading edge take some pitch out of the ones you have, much less $$$ to do it that way.
If it was me, I’d try the 12/18’s or repitched first and see what rpms and performance you get out of those. I’m sure you will gain rpms, it will be interesting to see if the 12/18’s get you back up to the oem impeller rpms range / speed or closer to the rated max rpm of 8000 and should get you back up to the oem top speed?
If I remember correctly, the tuner will only give about 5 hp at the stock rev limit of 8000 rpm, raising the rev limit to 8500 is where the 25 hp gain would be seen, but that requires a lower pitch impeller to get that many rpm.
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