42 cig new drives not producing. need help
 

My buddy has a 2000 42' cig Tiger. He changed out his bravo drives for xr drives with speedmaster lowers and is running a 5 blade hydramotive prop. He lost like 5 mph with the new drives. The new drives had 2" spacers in them so we took them out today thinking that it would get his speed back and tried it. It gained 200 rpm and shoots a 10' rooster tail now but didnt gain any mph. I think it runs alot better now and it doesnt porpis anymore. My question is what to do to get the mph back ? Are the drives to high is that why its shooting a rooster tail now ? Does it need a 6 blade would that help ? Do we need to put some more spacer back in ? should we have added more spacer instead of taking it out ?

I'm surprised it gets on plane with the shorties. We tried those on a friends 2000 Tiger and could not get the boat up.
As for 6 blades? trial and error.

Most guys find that the sportmaster skeg is too long.
Its longer than its predecessors and adds drag.

some guys cut it back-which is scary....how far do you cut?

Or you can buy an Imco lower and regain what you lost.


Uncle Dave

Oh- I forgot to add, I actually own both lowers

The imco lower is faster than the sport-master by at least 2 mph on my boats.

The imco lower is neither faster nor slower than my older Bravo 1 lower though.



Uncle Dave

It was really tuff for him he really had to ezz into it otherwise he would blow out.

As far as i know the sportmaster lowers are stock but you are right they are really long. I will let him no about the imco lowers.

Thanks guys anymore info much appreciated !!!!

I have a 2000 tiger as well, shorties wont work on it, i have xrs w 4 blades and I was told by some very knowledgeable people that the drive on a tiger needs to be deeper, i was told to put mine down a half inch, i just haven't had the time, depending on your power and setup. im at 625 and top speed so far has been 76.4..74 all day long

I have a fresh set of std XR lowers, im looking to get some shorties, if he is looking to go with std XR lowers, I would be willing to make a deal! PM me if interested

Also get rid of the 5 blades as they are stern raising and use 4 blades, also turning them in makes the boat carry better.

What pitch are u running with the 4 blade 27 or 28 ??

26 stock

I have been told before that you will actually go slower if you switch from a standard to an XR due to how the uppers are setup. I was told that the XR has straight cut gears that actually take more effort to operate causing a looss in speed due to the power it takes to overcome the differennce in gears.

but like i said i have just been told this. i have not done this on my own account. i have been told by a drive guy and another marine tech.

Just for grins...2000 Tiger with 750hp, stock XR's and 5 blade Herrings spinning out...84mph.

thats some good numbers. I think my buddys are 650 hp and with his stock bravos with 5 blades his best was 76.5

Stock 540 Bulldogs with 8/71's @ 6 psi...we're just guessing at the 750hp figure.

straight hull? GLH had merc 600's in his with xrs and was at 82. Have you had any drive issues with the blowers and the amount of torque?

Yeah, its a straight bottom...If I remember, GLH's 600's were a bit warmed over also.

He keeps up on them rather well...as soon as a problem shows up he has it opened up and looked at. A few gear sets and vertical shafts over the years but other than that he's golden.

My experience backs this up. I switched from B1X to the IMCO SC (same gears as XR) and lost a couple MPH. I will add that I went from 1.65 gears to 1.5 and had to change props....not sure if that factors in or not. Props were all four blade and back to original rpm's now.

I always heard that sportsmaster lowers are for boats running 90 mph. plus.