How Fast?
#12
Registered
Re: How Fast?
Yea, I guess Adam had to rebuild his motor's right after he bought the boat. I heard he bumped them up a little bit!! I know he is running tubed headers of some kind, they look like lightening's but I think he said they were something else!!
If I do motor upgrades it will have to wait until this winter or until something let's go in one of my motor's!! I've already missed TO MUCH of this boating season!!
And even then, I'm debating on weather to upgrade these motors on this boat or sell it and re-do another one I have my eye on with bigger motor's!!! Because if I do anything to make this boat faster I'd want to add Hydralic Steering!!
If I do motor upgrades it will have to wait until this winter or until something let's go in one of my motor's!! I've already missed TO MUCH of this boating season!!
And even then, I'm debating on weather to upgrade these motors on this boat or sell it and re-do another one I have my eye on with bigger motor's!!! Because if I do anything to make this boat faster I'd want to add Hydralic Steering!!
#13
Re: How Fast?
I have a 93 38 that we repowered in 2002 with 496 H. O.'s. Running Bravos with 1.36 gears 20P 4 blade and am gettting 64 on GPS at 4800rpm. It comes out of the hole like a rocket compared to the 502 EFI's it came with and no blowout. The downside is it feels like the props are creating too much lift and not allowing me to get any more speed. Love the boat but am getting antsy to go to something in the 42-47 ft range.
Keith
Keith
#14
Re: How Fast?
Originally Posted by kr1276
I have a 93 38 that we repowered in 2002 with 496 H. O.'s. Running Bravos with 1.36 gears 20P 4 blade and am gettting 64 on GPS at 4800rpm. It comes out of the hole like a rocket compared to the 502 EFI's it came with and no blowout. The downside is it feels like the props are creating too much lift and not allowing me to get any more speed. Love the boat but am getting antsy to go to something in the 42-47 ft range.
Keith
Keith
I would try 1.5 ratio gears with 22-24 pitch. This will increase your upper end greatly (3-5mph). Sounds like you have too much prop surface in the water. I know Houston prop hangs around here maybe he can shed better light.
#15
Registered
Re: How Fast?
I've heard that the reason they put the 1.36 gears in the bravo's on the 38 specials is that they are such a heavy boat. Something about the 1.36 gears not being under such a load????
The only way I can understand it is that, it would be harder for a drive to spin a 24 pitch than a 19 pitch......right???
As for the 3-5mph gain, that would be awsome!!! Why doesn't someone else try it first, and if you don't break anything I'l change mine!!!
I know of a 38 special with Bravo 3 drives and 454mags, he says ge gets about 64to 65mph (I don't know what ratio he is running though!!)
The only way I can understand it is that, it would be harder for a drive to spin a 24 pitch than a 19 pitch......right???
As for the 3-5mph gain, that would be awsome!!! Why doesn't someone else try it first, and if you don't break anything I'l change mine!!!
I know of a 38 special with Bravo 3 drives and 454mags, he says ge gets about 64to 65mph (I don't know what ratio he is running though!!)
#16
Registered
Re: How Fast?
Originally Posted by kr1276
I have a 93 38 that we repowered in 2002 with 496 H. O.'s. Running Bravos with 1.36 gears 20P 4 blade and am gettting 64 on GPS at 4800rpm. It comes out of the hole like a rocket compared to the 502 EFI's it came with and no blowout. The downside is it feels like the props are creating too much lift and not allowing me to get any more speed. Love the boat but am getting antsy to go to something in the 42-47 ft range.
Keith
Keith
#17
Registered
Re: How Fast?
I have a 2001 302 I just put 24 pitch 4 blade mirages on it and it made one hell of a difference. I had 23 pitch 3 blades and they blew out all the time and I couldn't trim the boat up very high. I tried 3 blade 25's and the same thing happend. With the 4 blades it jumps up and you can't blow them out but at higher speeds the a$$ end gets real loose compared to the 3 blades. Oh yeah I actually gained about 1.5 mph too.
#18
Re: How Fast?
Originally Posted by Ironmanwb
. Oh yeah I actually gained about 1.5 mph too.
thats good, most people lose that when going to the 4 blades. your cruise speed is probably higher too
#19
Registered
Re: How Fast?
Yeah my cruise is much higher about 7mph and I can plane at about 5 mph slower. I was turning the 3 blade 23's at 5250-5300 rpms thats why I had to change. Now I am in the 5000-5100 range much better on fuel as well.