SCX4 on Fountain Lighting 42
 

Current set up is 500EFIs and XR drives in 2001 Lightning 42
Re-power will be 632cu in NA motors @ 900HP

Initially thought about conversion to M6s but would be easier to buy a different boat.
Thoughts, feelings, suggestions on SCX4 with 6 lowers for this power and set up?

Prop Shafts are currently 5" below hull with standard length XRs.

Thanks!

Mine was a 99 42 converted from trip boat to full stagger twin by Fountain had reg bravos with sportmasters set up 1 inch below bottom I installed SCX -4,s so found out to high , prop blow out @ about 100 hard right hook to R and then tried again hard hook to L , put in 2 inch spacers worked out great .

@575Cat did that put your final prop shaft 1" above bottom? With SCX4 we should be 1" below bottom. Thoughts on that?

Yes I believe 1 above its been a few years ago .

From what I have read the -4 drive is supposed to be a surface drive - The bullet should be on top of the water not in it.
I am running a -3 at two inches above the lowest point on the hull. the water goes under the bullet on mine. (26 Daytona)
Why don't you run the standard SCX upper with the dual downshaft lower.
That is what I plan on running IF they make it in -3. OR I will have to run the -4 drive with a bigger prop or 1 inch spacer.

I don't think I would be too excited about the SCX-4

They really are not that strong especially when swinging an offshore CNC prop.

By the time you do a SCX-4 right you really should have an upgraded transom assembly, helmet, reservoir, HD Stainless Gimbal ring, WCM blueprinted lowers, maybe extension boxes, etc.

It really starts to add up plus dialing in with expensive props the "perceived" value and cost savings just really isn't there over other options.

I think there's more value in one of the other SCX drives running bravo maximums style props.

You could keep your lowers and get standard SCX uppers, or try one of the many SCX lowers also. I just don't believe it's worth the money to run a SCX-4 and spin a set of 12,000 props!

Arnesons are awesome drives but to keep it simply, not the best option at this time.

SCX,s require its own helmet and yes should have a large res .

I dont think you should go down the Arneson road .

and the SC lower will adapt with the correct coupler.........

https://cimg4.ibsrv.net/gimg/www.off...00117acc35.jpg
I have been running 875hp in a heavy old straight bottom 38 scarab for 2 years with no problems so far.

Subbed. I am hoping to swap my XR's to SCX on my 42 in near future....

I see something that I am interested in that has this combo, how many hours is "2 years" for you? 30 or 150?

https://cimg0.ibsrv.net/gimg/www.off...866ec999de.jpg

540ci with 8-71s 4% underdriven. So far the best mph with the scx's is 87mph @ 5200 rpm. I am raising the drive up another 1/2in. and testing it out this weekend. The 17 x 28 4 blade cleavers worked the best out of all the props i have tried. 30 and 32 bravo1 4 blades, 15.625 30 pitch maximus, 17x26 4 blade cleaver and a 17.5x 30 4 blade cleaver. Hopefully raising the prop will get me alittle rpm. My goal is to get it to run 90mph with 3/4 to full tank of and couple of people in the boat.

I have 65 hours on the drives.

I think that is the best route to go at this time. It is what Reggie III suggested as well (SCX4).
It is just to expensive to go M6 converstion. Better off selling and buying another boat.

I am extremely versed with Imco products, we sell and install a ton of them. Feel free to call me with any questions or should you want to purchase through me. Thanks Harris Performance 256-749-1584

This this Jeff? We connected on FB last week. I owe you a call still.

How was the conversion process? Any issues or were they really bolt on a go? with the hat change..

I had no issues, I changed to the imco HD gimble ring also. Everything bolted up as it should have with no problems.

https://cimg4.ibsrv.net/gimg/www.off...e484fa3c5e.jpg

SCX4 Upper w/160hrs
https://cimg6.ibsrv.net/gimg/www.off...2b6e8ab106.jpg

SCX4 Lower w/160hrs
https://cimg6.ibsrv.net/gimg/www.off...7571aedda9.jpg

SCX4 Lower w/less than 100 hours after IMCO rebuild


Mine-2002 38 Lightning w/700HP 160 hours
They were beginning to get hard to shift into N after running F for a while. Once in N they would shift like butter around the docks.
Pulled drain plugs and found metal, like the old Bravos would show before suicide. Note; SCX's don't have magnets on plugs so I installed that style.
One bad gear in Port side, one bad gear in Star side. Replaced all gears and bearings in both.
Pisser, YES.
But, they gave me warning signs, I didn't have to idle back to dock, lasted about 60 hours longer than an XR, and gave me confidence on the water.
Note; I broke these gears in at WOT trying to figure out props. I go WOT every time out.

My buddy's gear is far worse. 03 Lightning 750+HP SCX-4's
He blew one drive at the end of 2016. At that time I noticed his other felt like crap, talking green baby crap nasty!
He ran it all 2017 that way.
After last run of 2017 I convinced him to take it apart and this is what I found. He never even had to idle home.
I don't know what IMCO did/replaced when they rebuilt this particular drive. Could have been an upper, clean the lower scenario.
I put my old lower gears and bearings (the set that looked fine) with 160 hours on them in it. Time will tell, one summer almost done.

Testament to IMCO; I'd say the gears are tough