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larry9901
04-15-2011, 06:52 PM
Hello,

I currently have a regular Bravo on my 22c. It runs 80-82mph powered with a hp500.

I am highly considering putting a Bravo Sport Master drive on it.

I am looking for any feedback from someone that has done this.
Was there any noticeable performance upgrade with the drive?

On my 18c I had a alpha ss drive on it and there was a significant mph gain.

Thanks in advance
Larry

MDonziM
04-15-2011, 08:31 PM
What year is your 22? I think you would see more performance gain from possibly raising your x-dim depending on what it is now. I have always heard that a bravo doesn't really slow you down until you go over 80 mph and I am not sure how much better the sportmaster is hydrodynamically. I would think an Imco shorty would probably be better bang for the buck vs the sportmaster and achieve both aspects of efficiency and x-dim.

- Marshall

larry9901
04-15-2011, 08:51 PM
What year is your 22? I think you would see more performance gain from possibly raising your x-dim depending on what it is now. I have always heard that a bravo doesn't really slow you down until you go over 80 mph and I am not sure how much better the sportmaster is hydrodynamically. I would think an Imco shorty would probably be better bang for the buck vs the sportmaster and achieve both aspects of efficiency and x-dim.

- Marshall

Hi Marshall,

Thanks for the reply.

My 22 is a 87 I believe. Also, the x dimension has been slightly raised.
I am also going to look into the Imco:)
Larry

MOP
04-16-2011, 05:13 AM
The IMCO bolts on about 4+mph, Kens stock 385hp 22 went from 70 to 74-75 with the swap.

roadtrip se
04-16-2011, 09:56 AM
The factory did one C22 Sportmaster boat with a 525. My understanding from talking to people close to it, was that the boat didn't really run well with it.
Required lots of tabs and prop tweaks to make it work. If you talk to Mercury, they will tell you that this lower is set-up for boats that already have a high x-dim, like cats and high perf v-hulls. The skeg is very long, which would not be ideal for a C22, but I guess you could cut it.

I have run an IMCO shorty for ten years. A lot of other guys are running them now. They work. The more HP you have the better the performance gains, but even in stock HP you will see handling and speed gains too. You are going to need to revise your prop, because the slip factor goes up and you will need more pitch. The down side is the boat will run very flat and it takes more to lift the nose.

I have done a lot of set-up expirementing with this drive in the past couple of years and have some tweaks that really help with the handling, and durability, too. PM me, if you would like to discuss, further.

MDonziM
04-16-2011, 10:14 AM
Hello,

I currently have a regular Bravo on my 22c. It runs 80-82mph powered with a hp500.

I am highly considering putting a Bravo Sport Master drive on it.

I am looking for any feedback from someone that has done this.
Was there any noticeable performance upgrade with the drive?

On my 18c I had a alpha ss drive on it and there was a significant mph gain.

Thanks in advance
Larry


Larry,

One other thought I had was if you are really running 80-82 mph now you are only 2mph slower than Carls newer 22 with a 525 and a shorty so you are looking at spending a good amount, for in my opinion, a small mph gain. It becomes a pursuit of diminishing returns the faster you go. I have 625- 650 hp and have only seen 85mph or so but I still have prop work to do.

RT has a lot of experience with the shorty so I would take him up on his offer.

- Marshall

LKSD
04-16-2011, 07:48 PM
The Imco shorty's usually work rather well on most hulls. Especially where the X dimensions were set up conservatively. However from what I have found the results for actual speed gain will still vary a bit from boat to boat. We have been selling & installing them for years.. :) Jamie / Lakeside

Mr X
04-16-2011, 09:40 PM
The Sportmaster on the 22 Classic is terrible. We tried it on 2
different boats, one was the 525 as Tripper stated. The other was
a 496 Shelby. Both boats were corrected before delivery.

Mr X
04-16-2011, 09:42 PM
Larry,

One other thought I had was if you are really running 80-82 mph now you are only 2mph slower than Carls newer 22 with a 525 and a shorty so you are looking at spending a good amount, for in my opinion, a small mph gain. It becomes a pursuit of diminishing returns the faster you go. I have 625- 650 hp and have only seen 85mph or so but I still have prop work to do.

RT has a lot of experience with the shorty so I would take him up on his offer.

- Marshall
You should be running 89-90 when set up correctly, with that HP.

MDonziM
04-17-2011, 08:31 AM
You should be running 89-90 when set up correctly, with that HP.

I thought so too Ted but it hasn't happened. Strange thing is I can run 27" props to, say 5400rpm and 83mph or 31" props to 5000 rpm and 85 mph. These #s are from recollection. What do you think in general about cupping the bh props? When I first got the 31's the had a pretty heavy cup which I had reduced. (They came from a well known 20 cig with big power)

I took of my bennett tabs last spring to put 19" kplanes on and got tied up on another project and never put them on but would like to proptest more this yr. Any thoughts?

Thanks - Marshall

Mr X
04-17-2011, 12:10 PM
I thought so too Ted but it hasn't happened. Strange thing is I can run 27" props to, say 5400rpm and 83mph or 31" props to 5000 rpm and 85 mph. These #s are from recollection. What do you think in general about cupping the bh props? When I first got the 31's the had a pretty heavy cup which I had reduced. (They came from a well known 20 cig with big power)

I took of my bennett tabs last spring to put 19" kplanes on and got tied up on another project and never put them on but would like to proptest more this yr. Any thoughts?

Thanks - Marshall
I would run the 31's and have them checked by B-Blades. Also, prop timing is
critical on the BH. Make sure they are timed correctly.

larry9901
04-17-2011, 12:38 PM
I really never did check my x dimension. I don't remember how much I was told it was raised when I purchased the boat.

Although I was told it was raised. As it sits, the CMI headers do hit the hatch

I have a 25 Mirage done by VBlades that we turn at 5100'ish rpm.

The boat really does rock, and I do not have any problems getting it on plane.

I have spring fever now and want to do something!:boggled:
I also have a almost brand new spare long block I was considering doing something with.:eek:

Anyways, thanks for all the good info. I do appreciate it.

MDonziM
04-17-2011, 05:39 PM
I would run the 31's and have them checked by B-Blades. Also, prop timing is
critical on the BH. Make sure they are timed correctly.

Thanks Ted,

I'm certain that the timing is correct. You havn't heard of the effect of cupping in my setup? (the drive is mounted at standart bravo height.)
Do they ever thinout bh props?

- Marshall

VetteLT193
04-18-2011, 08:51 AM
All 1987's with the original 454 Alpha setup were higher from the factory. We compared to a much newer boat (Tidbart's) and it is just over an inch higher... an inch and 3/8ths is what I think it measured to. MOP's boat is the same way and I know he has an exact measurement.

The way the boat runs... I'd leave it exactly the way it is. A lot of people have spent a ton of money getting into the 80's and end up with a boat that doesn't run as good as this one.

Before messing with it, read as much as you can about handling issues, etc. that many owners have to overcome.

The reason why we originally checked the factory X location is when the HP500 went in. I started looking at pictures, etc. of others and the absolute confidence that Cuda had about it fitting. The end result was the way other 22's engines fit is lower. The giveaway was the air cleaner. It can't run anything higher than the short unit it has. The 2nd giveaway that finally had us measure is the headers rubbing the hatch as you said... and no one else seemed to have any fitment issues.

Another board member worked at the factory back in the day... (Budman?) and had verified to my brother that they were set up like that.

MDonziM
04-22-2011, 09:46 AM
I have a 94' and run the Hardin shorty headers which use the Gil performance risers which fit easily. 1"spacer and a 3" flame arrestor which will touch the eng hatch when you stand on it.