Nordic Heat - 600sci motor upgrades
03-04-2009, 10:58 PM
#31
Chris
Gold MemberThread Starter
Prop/Spacer testing update:
Went down to OCM today to test the boat with the spacer completely removed.
Thank you Tim, for getting this done while it was pouring rain last week.
As Steve commented, the 4 blade Bravo's were completely useless with the prop shaft only 3.5" deep, posting slip numbers between 22% and 24%. The best 4 blade speed was with a Bravo 32 @ 87.8 mph.
Now for the good news... Raising the drive removed about 70% of the chine-walking issues, and made the Hering props come into their own.
I initially tested my 27 Hering, and went 91.6 mph @ 5900 rpm. Very slight chine walk, but controlable. Because of the raised height of the outdrive, slip was about 9.8% This is only .3 mph faster than my previous best, but the boat was now controlable.
I was very pleased, but thought RPM was a little high.
Went back to OCM and Tim suggested that I triy his slightly massaged 29 Hering. (One of the two he likes running on the Flame), to bring the RPM down a bit.
WOWSER!!
93.3 mph @ 5700
Four runs, all between 92.9 and 93.3 mph
I am completely stoked!!
Tim and I are now arm wrestling, for the 29 Hering.
I am pretty sure I can take him...
Chris
Went down to OCM today to test the boat with the spacer completely removed.
Thank you Tim, for getting this done while it was pouring rain last week.
As Steve commented, the 4 blade Bravo's were completely useless with the prop shaft only 3.5" deep, posting slip numbers between 22% and 24%. The best 4 blade speed was with a Bravo 32 @ 87.8 mph.
Now for the good news... Raising the drive removed about 70% of the chine-walking issues, and made the Hering props come into their own.
I initially tested my 27 Hering, and went 91.6 mph @ 5900 rpm. Very slight chine walk, but controlable. Because of the raised height of the outdrive, slip was about 9.8% This is only .3 mph faster than my previous best, but the boat was now controlable.
I was very pleased, but thought RPM was a little high.
Went back to OCM and Tim suggested that I triy his slightly massaged 29 Hering. (One of the two he likes running on the Flame), to bring the RPM down a bit.
WOWSER!!
93.3 mph @ 5700
Four runs, all between 92.9 and 93.3 mph
I am completely stoked!!
Tim and I are now arm wrestling, for the 29 Hering.
I am pretty sure I can take him...
Chris
Last edited by CB-BLR; 03-04-2009 at 11:04 PM.
Platinum Member
03-05-2009, 08:35 AM
#34
Chris
Gold MemberThread Starter
03-05-2009, 08:42 AM
#35
Chris
Gold MemberThread Starter
Dave,
The Hering 5 blade Bravo props are about $1600 a peice.
This price includes having the props blueprinted, balanced, and adjusted if needed after running them on your boat.
Adjustment includes cupping, diameter reduction, trim ring removal, etc. Whatever is needed.
If the prop you purchase is not the correct pitch for your application, they will exchange it for the correct pitch.
Jeff at Hering is simply awsome to work with!
The props are hubless, and come splined for an XR shaft, to insure better balance, and lighter weight.
They also come with a teflon sleeve to insure a tight fit on the prop shaft.
They are works of art!
Chris
The Hering 5 blade Bravo props are about $1600 a peice.
This price includes having the props blueprinted, balanced, and adjusted if needed after running them on your boat.
Adjustment includes cupping, diameter reduction, trim ring removal, etc. Whatever is needed.
If the prop you purchase is not the correct pitch for your application, they will exchange it for the correct pitch.
Jeff at Hering is simply awsome to work with!
The props are hubless, and come splined for an XR shaft, to insure better balance, and lighter weight.
They also come with a teflon sleeve to insure a tight fit on the prop shaft.
They are works of art!
Chris
Last edited by CB-BLR; 03-05-2009 at 05:38 PM.
03-19-2009, 12:10 AM
#37
Chris
Gold MemberThread Starter
Best speed to date = 94.1mph - one run.
Could not duplicate it.
Average between 92.9 and 93.3
29 Hering 5 blade, 15" diameter, 5600 rpm
I am going to try a 28 Hering next, to get my rpm up to the target 5800 rpm.
Chris
Could not duplicate it.
Average between 92.9 and 93.3
29 Hering 5 blade, 15" diameter, 5600 rpm
I am going to try a 28 Hering next, to get my rpm up to the target 5800 rpm.
Chris
05-15-2009, 10:49 PM
#38
Chris
Gold MemberThread Starter
New personal best: 94.8 mph
The new trim tabs completely eliminate any chine walk, and the Hering 28 pitch 6 blade hauls butt!
I did three runs today over 94.4.
This trim tab placement works!
Chris
The new trim tabs completely eliminate any chine walk, and the Hering 28 pitch 6 blade hauls butt!
I did three runs today over 94.4.
This trim tab placement works!
Chris
Last edited by CB-BLR; 05-16-2009 at 12:41 AM.
