I have a 1988 170 Spectra with a 98 150XR6

[vernon]

If I go with a jack plate what type do you recommend and what set back 6" 8" or 10" it turns a 21pitch laserII at 5500 to 5700 right now, water pressure is 20psi a WOT

 

[vernon]

If I go with a jack plate what type do you recommend and what set back 6" 8" or 10" it turns a 21pitch laserII at 5500 to 5700 right now, water pressure is 20psi a WOT

 

[JW]

I'm surprised you're only turning a 21 Laser II. I had a 6" jackplate on my 1992 Pulse 171 with 1992 XR6, which is very similar to your setup. It would spin a 24" Laser II up to 5900 rpms, and a 26" Laser II up to 5500 rpms. That was with the 1.78:1 gear case, and I'm guessing you're spinning the 1.87:1 gear case. With 6" of setback, and the propshaft centerline set 3" below the pad, and a new 23" Laser II, you should be running pretty hard. Sounds like your motor is set all the way down on the transom?

 

[vernon]

my motor is set all the way down on the last hole when I lifted it up in a turn i lost my hook up

 

[JW]

OOHHHH, you want to TURN!! LOL

With a jack plate, you'll be able to adjust your motor up and down on your transom to find your sweet spot. You can buy a CMC manual jack plate for $200 brand new that will give you about 6" of verticle travel.

 

[vernon]

Thanks so a 6" jack plate, should water pressure be a problem if so at what point should I stop jacking it up?