difference tween 150 VRO and GT

[ibgood]

could someone plz tell me what was changed to make the 150GT a stronger engine than the 150VRO? i was told the only change was the jets in the carbs.

 

[Dhadley]

Re: difference tween 150 VRO and GT

The difference between a standard 150 crossflow and an XP/GT was the port timing and the cylinder heads. There are some carb differences in certian years but its more than jetting.

 

[ibgood]

Re: difference tween 150 VRO and GT

thanks a bunch, i was more than a little sceptical about the jets making that much of a difference between those models. gonna start looking for a dead GT to salvage some parts, thanks again.

 

[Dhadley]

Re: difference tween 150 VRO and GT

Before you spend a bumch of money, tell us more about your set up. You need to make sure youre getting everything out of what you have. Otherwise you may be very disapointed after a lot of work to "increase" your horsepower.

 

[ibgood]

Re: difference tween 150 VRO and GT

k, here goes. i have a 1984 Johnson 150hp VRO on a 1979 21ft Checkmate skiboat. my rpm's seem to be maxamized at between 5400 and 5500 at WOT. i have an aluminum 3 blade prop with a 15 inch diameter. Pitch is unknown, i see no visable markings on the prop. i measured the radius from center of the shaft to the edge of one blade and came up with 7.5 inches. was looking for more power for a better hole shot. at WOT it moves at about 41 to 42 mph. the only things i can think of for better takeoff is a stainless 4 blade prop and/or turning my VRO into a GT model. any more ideas would be greatly appreciated. thanks

 

[Dhadley]

Re: difference tween 150 VRO and GT

At 5500 we arent using all the available power we have now. And I can see your point about the holeshot especially pulling a skier. <br /><br />Have you tried mounting the motor higher? That will give you some rpm's and a better holeshot. The aluminum prop may not like the increased dimension but its worth a try. At least it should give us an idea about top rpm differences.