Imco 2" Shorties
 

What improvements did you see with the shorter drives on your V bottom boat. What speed , what rpm increases, were you able to prop up.

Tinkerboater What scarab do you have???? I was going to post the same question regaurding my 28' excell.

I have a 92 34 scarab with 600hp 502's boat does 75 gps now on flat water ( havn't been out in the rough without the rev limiter in the pasenger seat -WIFE ) usually gain about 3-4 mph. Just bought two IMCO 2" shortie lowers.

sound great. keep us posted on the results.

On a application that is nothing close to yours I gained 4 mph. Hard to say how much of that was in the proping or the lower unit.

Steve did you buy complete lowers or are you putting your gears in a shorty case? I'm very interested in trying the shorter lowers also...I talked to the Sonic factory and they told me with the X they were using when my boat was made I could use the 2" shorter lowers with no problem. Did you talk to Wellcraft? the guys told me I would need a 4 blade prop.....like 26 pitch Bravo 1.
Don

we put a pair of imco 2" shorties on a customer's 97 35' fountain.i didnt expect to see much improvment over stock drives.[we thought that fountain would have had the X as high as possible already]we gained 5 to 6 mph with no other changes.this was a high 90 mph boat to begin with.you have to run 4 blade bravo props with these gearcases

What change in handling is there when changing to a shorter drive/ amount of trim/bow position etc?? Why I ask is I have a porpoise problem at speed with a Baja 208 Islander and thought it might help. I know it's a small boat but DAMN I like it!!

Dyno I am just buying the lower case and shaft and using my gears. With the drives I have I need to trim the drives up to a reading of 7 to 9 on the mech cable indicators ( K type) for max speed and I feel this is loosing a lot of potential speed as well as better handling in the rough. ( This should make my wife happier)

I am already spinning 26 BRAVO 4 blades at 5400 rpm at 75 mph gps.

On a single engine boat such as a 26 Sonic or my 26 Scarab , these boats have a conservative "X" dimension and require alot of positive trim to attain top speed , wouldn't just adding the 2" shorty without a extention box slow the boat down because your losing leverage?