Best lower
 

Upgradeing my lowers from stock bravo1 to either imco or sportsmaster, for horse power upgrade, and need a nose cone with my application. what do you guys prefer.

Also 2 b1 lowers for sale 1 just completly rebuilt 10 hours ago and the other was done 50 hours ago. (offers)

I believe that IMCO lowers have proven to be faster than Sportsmaster lowers. I think that Max Machine is probably the fastest, but they are extremely expensive.

My opinion,
Chris

yes I agree mm is the fastest and merc the slowest you loose like 4 or 5 mph over a stock merc case, unless your over 90 which the merc can start to blow out [stock case ] I had good results with my imco 2'' shortie over a stock merc with nosecone picked up 5mph with imco.

So your saying that the imco will be 4-5 mph faster than stock b1 lower. i will be over 90 thats why i think nose cone will help. Thanks

I just bought Teague XR Plantinum shaft drive as my B1 was dying behind a 610 HP 540. It came with a -2 Sportmaster lower. So are you guys telling me I will likely go 4 to 5 MPH slower? I was running 84 -85 on GPS with a labbed 27 Mirage Plus. I think I am going to be sick.

The skeg on the Sportmaster is longer (mainly for high X on step bottom boats?) than the IMCO one and that slows you down bad. I don't know if anyone has trimmed the skeg to standard length and improved the speed though.

check the old sportmaster posts

http://www.offshoreonly.com/forums/g...ortmaster.html

labbed Sportmaster.
 

JohnB, thanks for the link. What ever happened when you filled the two outside slots? My x is deep, so I was hoping to pick up some speed with the -2 Sportmaster. Guess I should have done some research rather than just assuming -2 would be faster.

Didn't go with the Sportmasters because I had heard the Imcos were faster. My -2 Imcos turned out to be a good decision. I had also heard not so favorable things about nose cones.

While they are slower than a similar height drive. If your X is really deep it will be faster.
Steve

I recall filling in the outside 2 slots, as shown in the picture, worked. It reduced the water pressure and increased speed 1/2 to 1. I left the holes open in case of weed stuffing. Shorter is always faster, maybe 2 mph (or more) per inch depending on the boat. The problem is planning off, low speed slippage, higher overall prop slip, usually resulting in a prop change. More blades and a higher pitch can generally correct these problems.

It seems, from all I have heard, the IMCO is more streamlined and faster, at the same drive height.

The later model? sportmaster may be more efficient, the originals were real dogs. Their extra beef did prevent cracking of the housing just above the carrier, on very high X dimension cats.