Prop/Spacer testing update - Worried
 

I want to put this out to all you prop guru's:
I am now worried about the durability of my IMCO SC drive.

I have an 09 Nordic Heat with a 600sci that I have been doing prop and spacer testing for the last 6 months. Below is the table of my results. These are real slip numbers. Tach has been verified with a digital tach, and speeds with my analog GPS, my digital GPS and a radar gun.

The current best prop is a Hering 26 pitch, 5 blade bravo style prop. Slip is coming in at 5.2%

I am not the first Nordic Heat to post such low slip numbers. The Illmore 700 Heat regularly posts numbers between 6%-8% with the same drive and hull.

For you doubters:
Prop= 26 pitch Hering 5 blade bravo style prop
Speed= 83.8 mph
RPM= 5400rpm -- On the rev limiter

I am about to upgrade my 600hp motor to aproximately 750+hp using some upgrades offered by Whipple for my motor.

What I am worried about is that 750+hp and 5.2% slip on a 28 foot boat, sounds like a recipe for a broken drive.

What do you think??
Should I switch back to a 4 blade prop for reliability sake?
How much horsepower is safe in front of the IMCO SC drive?

I would like to hear some opinions.

Chris

I would run a 4 blade but that is just me my new engine has 750hp and i would never run a 5 blade. Some say that the 5 blade is better but slip can prevent damage, hooking up always breaks sh1t.

Steve Zuckerman was kind enough to introduce me to an outdrive guy in Nashville many of you know, Eric Betty. He coached me in rebuilding one of my B1s and deals with broken drives all the time. He understands the cause and effect of why they fail and the one thing he said that stuck in my mind was "slip is your friend"

The new 42 is bad ass

Chris needs the 34 cat at the Portland Boat show.
 

Tim,

Just send Chris your 34 from the boat show. Sounds like he would have fun with that!

No need for ANY upgrades...... except ... maybe a gas card!

Maybe a 5 - 10K limit.

Brad

Tim,

I really like my Heat!

But..................................

Having said that, an open-bow Heat with a Merc 850 and a NXT drive would be really great!

But since you are offering,
I will take a straight swap for the 42... or as stoutman said... the 34 cat.

And your gas card. ... limits are so prohibitave don't you think?

And then I woke up....
So back to my original question please.

Chris