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MDonziM
05-23-2008, 11:24 AM
What do think is the best (performance) drive setup for the following?

Now a 1994 22C orig. 502 efi/ bravo package. Added full Hyd. Steering. Building a n/a 540 estimated at 600+hp. I know the bravo will be near its limit but I was considering Putting on an Imco 2" Srorty.

Blackhawk seems ideal but I have no experience with them. Is it a waste to spend $ on a bravo (1" shaft) which should really be an XR?(1 1/4") How about 1.35 vs 1.5 drive ratio? Otherwise it would seem you need to run a lot of prop. (1.35 only with an XR I guess)

I never saw follow up on that 22 out west with the Illmore. The LH vs. RH rotation change (and handling claim)was really interesting. Anyone else take 4" of the X dimension?

Thanks in advance for your info/opinions.

MM

ITTLFLI
05-23-2008, 11:56 AM
I have a 1994 22 with the same set up. Call me if you wish to discuss. I will PM you my number.

Byron

zimm17
05-23-2008, 12:01 PM
I'm running probably 600HP through a bravo 1, 2" imco shorty, full hydraulic steering, with no outdrive problems so far. 1.5:1 stock ratio with a 29p four blade prop. You'll need a different prop for the shorty- something like a fusion 4, hydromotive QIV, or TXP. The turbo 1, or mirage will be worthless.

Conquistador_del_mar
05-23-2008, 12:20 PM
I'm running probably 600HP through a bravo 1, 2" imco shorty, full hydraulic steering, with no outdrive problems so far. 1.5:1 stock ratio with a 29p four blade prop. You'll need a different prop for the shorty- something like a fusion 4, hydromotive QIV, or TXP. The turbo 1, or mirage will be worthless.

I am also running a 29" pitch on my 600HP Eliminator Daytona with a 1.5 Bravo. What kind of speeds are you reaching? Have you tried some various props? If so, what is your best performing one? I have had a Hydromotive QIV for about 12 years now, but I am guessing there might be something better by now. Bill

zimm17
05-23-2008, 05:21 PM
I am also running a 29" pitch on my 600HP Eliminator Daytona with a 1.5 Bravo. What kind of speeds are you reaching? Have you tried some various props? If so, what is your best performing one? I have had a Hydromotive QIV for about 12 years now, but I am guessing there might be something better by now. Bill

Randy here on the boards is one of the prop gurus. I did some prop testing at the Donzi AOTH meet two years ago. The QIV and Fusion 4 were tied at top speed for me- at that time I didn't have the blower so I was testing 24p props and both went 71mph for me. The difference was the Fusion 4 (made by turbo) was 7mph faster at cruise- something like 50mph vs. 43mph at 4000rpm. I'm a little rusty on the numbers, but it was more efficient. In my signature, you can see I've hit 86mph at 5000rpm so far. I think I hit 90mph at 5200 if I had enough smooth water to try it. I'm told a 3 blade turbo TXP will give me 3mph more, but be scary loose on the water. The four blade keeps the boat tied down and handles nice. It also gets me on plane without using my tabs. The Fusion is billed as a rough water prop so it's made to scoop water, not really be a top end prop. Works great on my boat though.

Conquistador_del_mar
05-24-2008, 01:20 AM
Randy here on the boards is one of the prop gurus. I did some prop testing at the Donzi AOTH meet two years ago. The QIV and Fusion 4 were tied at top speed for me- at that time I didn't have the blower so I was testing 24p props and both went 71mph for me. The difference was the Fusion 4 (made by turbo) was 7mph faster at cruise- something like 50mph vs. 43mph at 4000rpm. I'm a little rusty on the numbers, but it was more efficient. In my signature, you can see I've hit 86mph at 5000rpm so far. I think I hit 90mph at 5200 if I had enough smooth water to try it. I'm told a 3 blade turbo TXP will give me 3mph more, but be scary loose on the water. The four blade keeps the boat tied down and handles nice. It also gets me on plane without using my tabs. The Fusion is billed as a rough water prop so it's made to scoop water, not really be a top end prop. Works great on my boat though.

Your speed is very comparable to mine. I am in the mid 90s at 5400RPM. I figured there must be a better prop out there after 12 or so years, but I guess mine is doing OK until I find out something better. Thanks, Bill

BigGrizzly
05-25-2008, 11:15 AM
I like the shorty, but I am not convinced of the speed potential on every hull with some trade offs. As for the 4 vs 3 blade the 3 is faster but handling can be an issue. Yes there are significant design changes in twelve years. The Hydro is really a copy of the original Mach Patriot which is closer th 15 years old or older. Every boat is different. Now in all fairness Road trips mirage Plus is modified and is un predictable. RT has been doing this a long time and I do not suggest that prop to anybody especially considering the small speed gain. As for the 1 1/4 prop shaft I feel it isn't necessary, unless it is the only way you can get stronger gears. I have well over 600hp and tun a 1 inch shaft and have not twisted it. as for the drive ratio stick with 1:50 ratio. if you go to 1:35 or smaller you will turn too small a blade and will loose speed and prop selection. Remember after 80 MPH the ball game changes on a 22 classic. My boat is a dream until about 80->83 then driving it becomes work and you uses up real estate in a hurry.

MDonziM
05-25-2008, 05:59 PM
Zimm - Did you do the eng upgrade and shorty at the same time or di u run the eng upgrade on the Brovo? So do you know what the shorty added in mph?

Thanks Byron- I guess I'll se how/when the eng build goes before I commit to a drive change.

Thanks Roadtrip and Randy. It is wild how sensitive these boats are to props. Last yr. I thought i might be up against the rev. limmiter so I put a "light cup" in my 25" mirage plus and promtly lost 400rpm and 5mph. Tried a 26" hydromotive intimidator 4blade, almost the same top end (70mph gps) but only could turn 4600 rpm. Handled well but was in flat water only.

MDonziM
05-26-2008, 07:04 AM
Roadtrip - I did replace my Bennett 9x12 dual ram with 12x12's last year with the manufacturer's specs on the transom and I think 1" above neutral on the trailing edge. What do you mean by "way above"?

Thanks- MM

MDonziM
05-26-2008, 06:05 PM
MadPoodle - So what is that 1 1/4 to 1 1/2 " ? I'll have to go measure mine.

Conquistador_del_mar
05-27-2008, 11:28 AM
I like the shorty, but I am not convinced of the speed potential on every hull with some trade offs. As for the 4 vs 3 blade the 3 is faster but handling can be an issue. Yes there are significant design changes in twelve years. The Hydro is really a copy of the original Mach Patriot which is closer th 15 years old or older. Every boat is different. Now in all fairness Road trips mirage Plus is modified and is un predictable. RT has been doing this a long time and I do not suggest that prop to anybody especially considering the small speed gain. As for the 1 1/4 prop shaft I feel it isn't necessary, unless it is the only way you can get stronger gears. I have well over 600hp and tun a 1 inch shaft and have not twisted it. as for the drive ratio stick with 1:50 ratio. if you go to 1:35 or smaller you will turn too small a blade and will loose speed and prop selection. Remember after 80 MPH the ball game changes on a 22 classic. My boat is a dream until about 80->83 then driving it becomes work and you uses up real estate in a hurry.

I am also turning a 1" shaft and 1.5 ratio Bravo drive with no problems so far with my 600HP blown BBC. What prop do you think I might try on my 23' Eliminator tunnel hull other than the Hydromotive QIV for a possible better top end speed? I have not taken it out since installing an Extreme IMCO lower end, but I really doubt that it will make much difference since I had a nose cone on the Bravo. Thanks, Bill

BigGrizzly
05-27-2008, 04:27 PM
Is your Imco short compared to the bravo? If it is you will be up in the 30 inch pitch, Other wise the Fusion may be the answer in a29 0r a 30. The fusion has more bite then the Hydro, but testing is the only way. If your Imco is real short a 5 blade may be in order.

Conquistador_del_mar
05-27-2008, 07:45 PM
Is your Imco short compared to the bravo? If it is you will be up in the 30 inch pitch, Other wise the Fusion may be the answer in a29 0r a 30. The fusion has more bite then the Hydro, but testing is the only way. If your Imco is real short a 5 blade may be in order.

The Extreme I installed is the same drop as the Bravo so there will not be a difference there. Does the 4 blade Fusion usually produce better speeds than the QIV of the same pitch with the same RPMs or does the RPM also typically change? I presumed the Fusion is a 4 blade. Bill