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32offer
05-10-2007, 05:59 PM
I recently upgraded to a Prostar 197 from a '92 Prostar, so naturally I've got quite a bit more power. I went from 44mph to about 55 mph. I am going to need to get my prop repaired on the new ('02) boat. It is a 13" x 13" OJ S.S. 4-blade. I was thinking about changing sizes to maybe get better fuel economy with gas prices skyrocketing. I would even be ok loosing a little holeshot power, as I don't use anywhere near full throttle as it is. I primarily pull up 180 lb slalom skiers and barefooters.

dsoby
05-10-2007, 06:06 PM
55? That's way faster than I've ever heard of a 197 going. 13X13 is the standard prop for a 1:1 transmision. Alot of folks are switching to an Acme 541 3 blade. It seems to be smother and quicker than the standard OJ 4 blade.

PendO
05-10-2007, 11:12 PM
I recently upgraded to a Prostar 197 from a '92 Prostar, so naturally I've got quite a bit more power. I went from 44mph to about 55 mph. I am going to need to get my prop repaired on the new ('02) boat. It is a 13" x 13" OJ S.S. 4-blade. I was thinking about changing sizes to maybe get better fuel economy with gas prices skyrocketing. I would even be ok loosing a little holeshot power, as I don't use anywhere near full throttle as it is. I primarily pull up 180 lb slalom skiers and barefooters.

http://www.waterskimag.com/product.jsp?ID=61546&product=boat&clientID=17146

What engine do you have ... unless you have an 8.1L or some supercharger setup you need to verify your speed with GPS, as the LQ9 in a 2002 197 (pre-hook) ... will allegedly top out @ 47.2

boat Specifications:
Year2002Length Overall (Feet)19Length Overall (Inches)8Displacement2800Fuel Capacity28Load Capacity1340Seating Capacity10Acceleration to 36 MPH (seconds)6 seconds; 170.3 feetNoise at 36 MPH89 D 92 RNoise at Idle59 D 61 RTest EngineIndmar LQ-9 6.0L EFI 385hpTest Prop14 x 20 OJ 4-bladeTop Speed47.2

dsoby
05-11-2007, 08:56 AM
The "pre-hooked" hull on this boat was a bit faster than the hooked version but only by about 1-2 MPH. I believe that I clocked mine at 50 on a GPS before hooking it.

3event
05-11-2007, 09:48 AM
Wow, 55mph. How many hours, options, what engine? Maybe I'll trade you for my 02 with the Predator :D . I get 47.2mph with a 3blade 14pitch. Hull is stock, no hook added....yet. As for fuel economy, I have no idea - I just keep feeding her when she needs it. Summer's too short here to worry too much!

Check this thread for prop performance info....
http://www.tmcowners.com/teamtalk/showthread.php?t=11251&page=3

32offer
05-15-2007, 12:07 PM
Well....at least that's what my speedo AND Perfect Pass are reading. I just bought the boat a couple weeks ago and haven't had it in the slalom course yet to time it or GPS'd it, so it could definitely be a little off. It feels a lot slower at 36 mph while skiing than my last Prostar did. So say it's off by 5-6 mph at 55mph, it would be a couple mph off at 36 mph.

dsoby
05-15-2007, 02:38 PM
The speedo and the PP get their input from the same source (paddle wheel). You can calibrate the speedo and PP in the wakeboard mode with a GPS but I'm pretty sure that the slalom mode must be calibrated on a course using magnets or the smart timer.

#47of100TeamMC
05-15-2007, 03:24 PM
I have a 2002 197 TT with LQ9 and Powerslot, Hooked hull Stock OJ 4 Blade. I'm seeing 52.8 on top end. 34.2 and 36 are verified in the course and GPS as spot on.

TRBenj
05-15-2007, 03:51 PM
I have a 2002 197 TT with LQ9 and Powerslot, Hooked hull Stock OJ 4 Blade. I'm seeing 52.8 on top end. 34.2 and 36 are verified in the course and GPS as spot on.

Did you verify the 52.8 on GPS?

The only reason I ask is because Ive set speedos in the course at slalom speeds with the smart timer, and PP is still off on the top end by ~3 MPH (reads 49, actually 46 according to GPS). One would think that calibrating the paddlewheel in the course would make it read correctly at all speeds, but it doesnt!

32offer
05-15-2007, 03:56 PM
What is this "hooked" hull everyone speaks of? Some sort of modification? What is the reason and what does it improve?

BrianM
05-15-2007, 04:11 PM
What is this "hooked" hull everyone speaks of? Some sort of modification? What is the reason and what does it improve?
The 'hook' was introduced on the 2002 TT boat. It was made standard for all of the 190/197s in 2003 and is the same today. The way I understand it it just causes the rear of the boat to lift a little bit improving the wake.

dsoby
05-15-2007, 04:39 PM
What Brian said. It is possible to add the "hook" to the transom and have it gelcoated. The mod greatly flattens the wake, reduces shortline spray, and improves tracking. Some pre 02TT boats had a wing on the rudder for this purpose but the flare turned out to be a permanant fix.