Boater8987

This season I switched over to 2" shorty XR Sportmaster lowers and lost 3-4 mph. I kept the same gear ratio 1.25 to 1 and props 36P bravos. I played with drive spacers and ended up with the same stock X, with a 2" spacer =stock. Has anyone else had this problem. I talked to Merc HP and they said the boat may be slower, but the drive housings will be stronger, due to the larger mass. Has anyone else had this problem? My props were already labbed. Thanks for the imfo. Gary

John the Drive Man

Yes, unless you have an 80 -85 MPH boat shorties will slow you down. Also if do not have an extension box, you will also
more than likely slow down. A step in the bottom of the boat
will make a difference also. But the major thing is, if the boat is not well over 85MPH shorties will slow you down.

MDGperformance

Gary i have found that the original bravo lowers with the hydromotive nose cones(installed at spectre factory) are a little faster than the sportmasters,the reason being the sportmasters have a little wider housing and awider skeg,but i think the sportmaster lowers give you a little better handling and a stonger unit,i have also found that adding around 70lb of weight in each sponson(middle bulkhead)really helps settle boat in.As far as the shortie goes your propshaft is already above bottom of boat,i think around 1.25,so a shortie won't give much prop bite,i have heard of someone using herring 6-blades and shorties.I liked running the 34 pitch bravos(sometimes stock)on the spectres you need to let them wind up to around 6000 awesome acceleration and a top end around 120-125 usind 1.35 gear.

Boater8987

Thanks for the info Guys. Hey Dave you are right about the XR with nosecones from Spectre. I hated to git rid of them but the housings around the carrier retaining ring started cracking at the top. I had them repaired a couple of times. I pmed you a while back on the weight of the ballast. All that lead shot in my boat came out of the bags in both sponsons and traveled to the rear bilge area. Man was that fun to clean up. Now the boat will not take a set as good as it did. I wanted to know is there a better way to secure the ballast and what was the weight? Also where do I purchase ballast? I did try 1.5 spacers but lost bite and trim. So now I am back to shorty + 2" spacer and have the two 1.5 spacers for sportmaster avalible if anyone needs a set. I also run the 34 P on days when am just playing around here local and the 36p for poker and radar runs. John, thanks for your input too, I was hoping you would respond. Come on Mark buy my Rhino

Boater8987

Just lika a woman, she got a $100,000 + boat and you can't even get a cheap Rhino. Thats gratitude for you. Good thing she at least lets you drive the boat around.

racer-x6

I had the same results

VetteLT193

With the higher X the old props are what is slowing you down. You need more blades or at least more pitch to handle the change.

Look at other boats with an aggressive X and you almost always see more blades. I can't believe Merc didn't start with that as the first suggestion considering they make the Maximus prop for this exact reason.

Boater8987

Vette I am running the same x as I was with the original xr's. I am running the 2" sport masters with a 2" spacer=stock from Spectre, but they had added nose cones to the xr's. As Dave from MDG said they are a faster setup. By the way this is an original MDG boat, he is a Spectre Dealer. Me being the way I am, always having to screw around with a proven great running package, which ran a best of 129.8 mph with 575's and the fact that the housings on the lower xr's were cracking felt I needed to do something. Ralf from Pro Rock, where I picked the boat up at, told me about his sportmaster with #6 drive prop shaft conversion and thought the boat might run faster with the # 6 props. So I purchased 2 shorty sportmaster lowers and 2 -34P x 16.5 4 blade six props. First time out 100mph,struggle to get there, no trim and bow plowing. Talk to prop shop said I needed to reduse diameter and add spacer. OK, redused to 16" diameter, added 1.5 spacers boat ran 110. Still no trim and bow plowing, but getting better. Talk to prop shop said needed to reduse diameter more, too much stern lift. Sent props back, cut down to 15 1/8 boat ran to 115, still no trim and boat was prop walking to the right at 115. Went to 2"spacer regained some trim, but still walking to right at 115, not a good feeling. Moral of this story, boat did not come close to running like the xr 4 blade bravo setup. I would say the factory and MDG had it perfect, but I just had to screw with it and threw away alot of money for nothing. So I traded Ralf back the #6 prop shafts for xr and took a beating selling the #6 props. Now its back to the great handling and very fast for the power Spectre I originally purchased, less a few mph because of the added mass of the sportmasters. Merc HP agreed the Spectre's like the 4 blade bravo best. One thing that was different when it was stock was that I was running 129.8 with stock 36 bravo and with the sportmasters I have been running labed 36. I have now purchased stock 36's and will give that a try in the spring. Thanks for everyones input, it gives me food for thought. Gary

VetteLT193

dang, you've been through it all it seems.

Boater8987

Yes Mark that was us. It was rough that day! I remember seeing your boat at Tims in the morning. I live up in Aquia Creek past the RR bridge on the left beside Hope Springs Marina. When you see me wave me down, you can get a ride no problem. Also I will be joining the ranks of you CC guys. My neighbor and I,he owns Aquiaboatsales.com and Aquiaboatstorage.com we are getting a Glasstream dealership. I have a new 32 CC being built right now optioned to the max, with cabin a/c,radar,dvd, 300 verados etc. Supposed to deliver 1st week of Jan. We will be at the Richmond boat show on the 18th of Jan, with our boats for sale and will be attending OSO party. His name is Garry also, he talked with you at Smithfield station at the Jamin on the James and you told him how you got on plane after blowing a powerhead. Here is a couple of pics. Come on by and see us at the show if you like and anyone else out there is welcome too. Jan 18-20th Richmond boat show. Here are a couple of pics so far. Let me know what you guys think. I high jacked some other OSO members paint design and colors and changed them around a bit. Hope he does't get mad. But I thought his boat looked awesome. Gary