Bravo1 1:5 ratio vs 1:65 for strength and wear.
09-15-2016, 09:03 PM
#21
Gold Member
Gold Member
Through testing on two of my own boats, I have no idea why they put DWP on deep V boats. If you have steps and a high X dimension than I totally understand. But, on any true deep V you are in the basement and dont need the pickups in the nose/bullet.
That being said, I think a lower with no pickups in the bullet is worth 2+ MPH. My 302 went faster and my 342 went a solid 2+ maybe 3 faster. No difference in engine temp and maybe even better handling.
Anybody can test it in 15 minutes. Buy a allen plug kit for $10, drill & tap the nosecone holes, screw in the plugs with a little lock-tite and you are done. If you arent happy, take them out. They were simple, like 1/4 or 5/16. A houseplant could do it in 20 minutes on a twin.
That being said, I think a lower with no pickups in the bullet is worth 2+ MPH. My 302 went faster and my 342 went a solid 2+ maybe 3 faster. No difference in engine temp and maybe even better handling.
Anybody can test it in 15 minutes. Buy a allen plug kit for $10, drill & tap the nosecone holes, screw in the plugs with a little lock-tite and you are done. If you arent happy, take them out. They were simple, like 1/4 or 5/16. A houseplant could do it in 20 minutes on a twin.
09-23-2016, 06:31 PM
#22
Registered
Fountain used the 1.65's in some of the 35 Executioners with the 496 Mag HO's, helped the boats run a bigger top end number, but they were long legged in getting there. All in what you want in YOUR boat. This chit was a couple MPH one way or the other, personal choice.
Last edited by RaggedEdge; 09-23-2016 at 06:34 PM.
09-28-2016, 01:10 AM
#25
Registered
XR efficiency
My buddy bought a 93 26' velocity P6 class race boat this spring.
It had a 1.65 gear drive on it...the engine that was in it didn't start coming on til 5k,
anyway, we ran it with the 26 bravo that it came with, then a 28 and then a 30, it ran 80 with the 30,
fast forward a few months, he has a new engine being built, and a XR (1.5 ) built for that too.
We put the XR on the boat with the current power, the best it would run is 73 with the 26 on it.
The 1.65 gear drive is a side water only pick up with the skeg cut down, the XR is a dual water pick up with the stock skeg.
The XR uppers do consume more power, but I cant believe the skeg and the 4 water pick ups in the front of the gearcase
would play that much of a role in the difference.
Must be some truth to the saying of a turning a big prop slower is more efficient.
The new engine ( with a much more user friendly power band) went in just days before the shootout, didn't get much dial in time, but
did manage to get it to 88 with a 30 and the XR...I have a set of 1.5 helical gears that I want to put in place of the 1.65's and see
what that will do
It had a 1.65 gear drive on it...the engine that was in it didn't start coming on til 5k,
anyway, we ran it with the 26 bravo that it came with, then a 28 and then a 30, it ran 80 with the 30,
fast forward a few months, he has a new engine being built, and a XR (1.5 ) built for that too.
We put the XR on the boat with the current power, the best it would run is 73 with the 26 on it.
The 1.65 gear drive is a side water only pick up with the skeg cut down, the XR is a dual water pick up with the stock skeg.
The XR uppers do consume more power, but I cant believe the skeg and the 4 water pick ups in the front of the gearcase
would play that much of a role in the difference.
Must be some truth to the saying of a turning a big prop slower is more efficient.
The new engine ( with a much more user friendly power band) went in just days before the shootout, didn't get much dial in time, but
did manage to get it to 88 with a 30 and the XR...I have a set of 1.5 helical gears that I want to put in place of the 1.65's and see
what that will do
