Does anybody know if the lower has has been slim down or did they just add a bullet to the nose.If that was the case i dont why you couldnt adapt a imco nose cone to the old scx lower.

its a 4'' shortie. its a new upper and lower case.

i understand they redesigned the upper and lower to make it shorter. The -4 does not interest me since i can mount the old scx in a surface drive prop shaft depth if i want.The design of the bullet and shape the lower does interest me. from a glance besides it being shorter it looks like the old scx with a imco bravo nose cone. im not talking bad about the drive .i just dont want to sell my old scx to get a drive that is 2 inch shorter with a nose cone.

Your forgetting the most important part. The ability to run a true surface style prop which is larger in diameter....like a #6 or a hering. Your current scx will not.

You can run a speed master prop on the old scx with a propshaft change.Im not being a hater.I can see if you didnt already have the old scx it would be the way to go.I just think the only real big advantage over the old one is the design of the new lower.Which i think could be duplicated with maybe a nose cone on the old scx lower.

Yes you can change the propshaft but the new SCX4 upper case is also an advantage with the curved cavitation plate to allow for a larger prop along with the higher prop height. How would you accomplish the higher prop height on your current setup?

IMCO tested multiple nosecone options on the old scx with no speed gain. There is a trade off, you gain strength with the larger gears but more drag, thus lower speed. I understand where you are coming from and do not think you are a hater. You could also have Wilson Custom Marine Blueprint your current lower.

great info,so if they didnt pick any speed on the old lower with nose cone.how is the new lower faster.It cant be much thinner
it has the same gears.

It looks like you can run a larger diameter prop 6 style allowing to raise the bullet higher out of water creating less drag as you can see a longer skeg to keep control at high speeds,looks awesome the scx is a great drive but the lower wasn't liked much this looks like imcos answer,would love to try a set on my donzi zrc as i am running imco -3 now and work great,just need to hit the loto for some whipples and scx -4

sc-4 drive arrived today. have 2 props to try, a herring and merc. lower is 1.5 so expect a 32x16.5 will be about right. steve will try on his boat within the next 2 days. will post results. this is probably the first single engine cat tried with this drive.

Its not just the new lower that gained the speed. Its the combo of the lowers design, added to less drag since its raised up, and most important the much more advanced surface style prop. At $5400 each for a hering 5 blade they must be doing something!