Impeller gp1300r, make it clear once for all!

[Swedoo]

Once for all, after all years the gp1300r npv with the ho pump has been around many people has tryed different prop setups.

So, is it possible to pull a dynafly 14/20 on a stock motor ?
ive seen people says its possible with the 87mm nozzle and some says it wont.

only mods i have is ppk, sealed shoe, riva rideplate, 800 grate and stepped sponsos.
Its a 06 ski with a fresh motor (20hours)

Run with a stock prop now but recently bought a dynafly 14/20 and a skat 13/19.
Im looking for more speed but wont loose to much acceleration.

[SJ-(KY)]

Great question!I would like to know this as well...

[Prism]

I personally own a 2006 GP1300R with NO engine or airflow mods except a d-plate. Other mods include an 800 grate, modified R&D rideplate, sealed shoe, Solas Dynafly repitched to 14/21 by WFO, and an 87mm exit nozzle sanded slightly to 88mm. It turns the 14/21 7160-7200rpm @ 70.8mph depending on weather and temp. A box stock 14/20 with a stock 87mm GP1200R nozzle should turn about the same rpm.

[mikegp]

I personally own a 2006 GP1300R with NO engine or airflow mods except a d-plate. Other mods include an 800 grate, modified R&D rideplate, sealed shoe, Solas Dynafly repitched to 14/21 by WFO, and an 87mm exit nozzle sanded slightly to 88mm. It turns the 14/21 7160-7200rpm @ 70.8mph depending on weather and temp. A box stock 14/20 with a stock 87mm GP1200R nozzle should turn about the same rpm.

i honestly going to said this, give wfo a call one more time and revise that prop pitch with him again.

[mikegp]

Once for all, after all years the gp1300r npv with the ho pump has been around many people has tryed different prop setups.

So, is it possible to pull a dynafly 14/20 on a stock motor ?
ive seen people says its possible with the 87mm nozzle and some says it wont.

only mods i have is ppk, sealed shoe, riva rideplate, 800 grate and stepped sponsos.
Its a 06 ski with a fresh motor (20hours)

Run with a stock prop now but recently bought a dynafly 14/20 and a skat 13/19.
Im looking for more speed but wont loose to much acceleration.

if it's bone stock , you maybe able to turn the 14/20 but it will be a turtle out of the hole and slow as hell , i will keep the 13/19.
just as a example , my non pv 1300r , had R&D heads , 4* key , VF3 reeds , no air filters or flame arrestor ,dplate , riva EFI controller , and so and so .
it was running 76.3 with a full thank of fuel on a true 14/21 .
you can do your own math.

[Prism]

if it's bone stock , you maybe able to turn the 14/20 but it will be a turtle out of the hole and slow as hell , i will keep the 13/19.

Thats another benefit of the 87mm nozzle. Less load on the engine all the way around. I can tell you from personal experience that mine DOES NOT accelerate any slower out of the hole than stock...and if it does, I can't feel it.

[mikegp]

if it's bone stock , you maybe able to turn the 14/20 but it will be a turtle out of the hole and slow as hell , i will keep the 13/19.

Thats another benefit of the 87mm nozzle. Less load on the engine all the way around. I can tell you from personal experience that mine DOES NOT accelerate any slower out of the hole than stock...and if it does, I can't feel it.

you can use a 87 ,85 or 90 just saying bone stock does not have what it takes to move properly anything bigger than 13/19.
can imagine for a second how slow yours is with a bone stock engine and a 14/21 . it's hard to believed wfo suggest that.

[Prism]

if it's bone stock , you maybe able to turn the 14/20 but it will be a turtle out of the hole and slow as hell , i will keep the 13/19.

Thats another benefit of the 87mm nozzle. Less load on the engine all the way around. I can tell you from personal experience that mine DOES NOT accelerate any slower out of the hole than stock...and if it does, I can't feel it.

you can use a 87 ,85 or 90 just saying bone stock does not have what it takes to move properly anything bigger than 13/19.
can imagine for a second how slow yours is with a bone stock engine and a 14/21 . it's hard to believed wfo suggest that.

WFO didn't suggest anything. I just bought a used Dynafly off of him that was pitched. The tuning and setup are my own. Have you tried this yourself, or are you relying on what everyone else does and says? Changing the exit nozzle is like changing rear end gears in a car. With enough gear, a Ford Focus could move a tractor trailer. I'm just sharing what I know as true from experience. For me it worked very very well.

[05 green gp]

Once for all, after all years the gp1300r npv with the ho pump has been around many people has tryed different prop setups.

So, is it possible to pull a dynafly 14/20 on a stock motor ?
ive seen people says its possible with the 87mm nozzle and some says it wont.

only mods i have is ppk, sealed shoe, riva rideplate, 800 grate and stepped sponsos.
Its a 06 ski with a fresh motor (20hours)

Run with a stock prop now but recently bought a dynafly 14/20 and a skat 13/19.
Im looking for more speed but wont loose to much acceleration.

if it's bone stock , you maybe able to turn the 14/20 but it will be a turtle out of the hole and slow as hell , i will keep the 13/19.
just as a example , my non pv 1300r , had R&D heads , 4* key , VF3 reeds , no air filters or flame arrestor ,dplate , riva EFI controller , and so and so .
it was running 76.3 with a full thank of fuel on a true 14/21 .
you can do your own math.

the efi control you have is it a 6 adjustments or four? what are your setting at?

[Prism]

if it's bone stock , you maybe able to turn the 14/20 but it will be a turtle out of the hole and slow as hell , i will keep the 13/19.
just as a example , my non pv 1300r , had R&D heads , 4* key , VF3 reeds , no air filters or flame arrestor ,dplate , riva EFI controller , and so and so .
it was running 76.3 with a full thank of fuel on a true 14/21 .
you can do your own math.

No math needed Mike. My single pipe 2003 w/o port grinding, milled stock head, and the rest of the goodies turns a 15/23.5 Dynafly 7380 rpm 77mph LOCKED DOWN to the water through an 86.5mm nozzle. Nearly zero cavitation from a stop and the acceleration wants to rip the ski out of your hands in the mid range. (and thats with my 240lb+ fat ass on it) I usually pitch my own props and nozzles.

Getting back to the question at hand. IMO a 14/20 can be used in a stock motor ski using an 87mm nozzle. The rpm will be 7100+ which is enough to get the engine in its powerband which in turn will keep the acceleration in check. But if you want to keep repitching and waiting its up to you.