Any 28 owners with big HP??
#1
My 28 Pantera hull is as close to a Cig as one can get. I did a huge conversion this winter and am not getting anywhere near the speeds I should.
Here are the speeds at different RPMs and different props.
Hoping someone here has 900+ HP in a 28 single and let me know what is reasonable for slip numbers.
I've tried a standard lower and shortie. I know I'm in the unknown area as I'm running a Konrad with an 8" set back.
Thanks
Here are the speeds at different RPMs and different props.
Hoping someone here has 900+ HP in a 28 single and let me know what is reasonable for slip numbers.
I've tried a standard lower and shortie. I know I'm in the unknown area as I'm running a Konrad with an 8" set back.
Thanks
#2
It's not impossible, but I don't know that you are going to find a single engine 28. I am repowering a 28 and CONSIDERED a single big power big block with a SSM 6. The problem is that 28 Cigs have a huge (tall) center stringer that would have to be really hacked up to put in a single big block. We opted to go with twin blown smallblocks and XR platinum drives.
Barry
Barry
__________________
Thanks, Barry
Driver - High's Fuel Your Journey Cigarette Racing Team #598
Thanks, Barry
Driver - High's Fuel Your Journey Cigarette Racing Team #598
#3
Ouch!.........I'm in extreme pain just looking at your slip sheet. I knew the 28 Pantera was difficult on speed, but 900hp and 83mph hurts............
Ok, the dumb questions:
Is the drive height high enough with the 8" set back?
How's the bow lift feel?? Hooks in the hull?
Really have 900hp??
I find on my 27 I need ALOT of trim angle to get the last bit of speed, even though it's porpoising - damn TRS...........
Only GPS run I did was with 620hp, at 76mph w/28 bravo spinning 5,200 (before I really learned what the boat liked), and I seem to remember running the slip #'s and coming up with maybe 17% ?? or is it 20?? I now run a labbed 29p Mirage Plus at 5,100 - because of the deep drive, and 4 blade torqued hull over too much - seems to be about same speeds - but not GPS tested
I was planning to go to a Konrad this winter, so I'd love to know more about your setup.
I remember Dave Govatos, from this area, was at those speeds with a 28 Pantera raceboat in early 90's with both a TRS, and a Bravo on a box (neither of which held up of course) with maybe 800hp ?? Not sure what power level he finally got to - got sick of blowing drives, and not going any faster - I'll have to ask him...........
Also, rpms for lower speeds might help confirm whats going on...................
Pic is at cruise only...............
Eddy
Ok, the dumb questions:
Is the drive height high enough with the 8" set back?
How's the bow lift feel?? Hooks in the hull?
Really have 900hp??
I find on my 27 I need ALOT of trim angle to get the last bit of speed, even though it's porpoising - damn TRS...........
Only GPS run I did was with 620hp, at 76mph w/28 bravo spinning 5,200 (before I really learned what the boat liked), and I seem to remember running the slip #'s and coming up with maybe 17% ?? or is it 20?? I now run a labbed 29p Mirage Plus at 5,100 - because of the deep drive, and 4 blade torqued hull over too much - seems to be about same speeds - but not GPS tested
I was planning to go to a Konrad this winter, so I'd love to know more about your setup.
I remember Dave Govatos, from this area, was at those speeds with a 28 Pantera raceboat in early 90's with both a TRS, and a Bravo on a box (neither of which held up of course) with maybe 800hp ?? Not sure what power level he finally got to - got sick of blowing drives, and not going any faster - I'll have to ask him...........
Also, rpms for lower speeds might help confirm whats going on...................
Pic is at cruise only...............
Eddy
#4
I have a Konrad. Great product. See my Conversion in the Pantera section.
I too get huge roll onto the port side. Bleeds off speed big time.
I tried a spacer and shortie lower, not much change at all.
Email me if interested in teh Konard. I have done the conversion myself and am a dealer for them. I know everyone at the plant.
Kirk
I too get huge roll onto the port side. Bleeds off speed big time.
I tried a spacer and shortie lower, not much change at all.
Email me if interested in teh Konard. I have done the conversion myself and am a dealer for them. I know everyone at the plant.
Kirk
#6
That's because the 27 Magnum, while the same basic hull had a different stringer set up. Many came orinal with single big blocks.
__________________
Thanks, Barry
Driver - High's Fuel Your Journey Cigarette Racing Team #598
Thanks, Barry
Driver - High's Fuel Your Journey Cigarette Racing Team #598
#7
Thought about your roll over issue - With my deep TRS and 28 Bravo one I would get prop torque roll over real bad unless I trimmed it way, way out, inducing lotsa slip. 3 blades don't seem to do it. Is it possible that your drive is still too deep, even when you tried the shortie?? Might explain why ther is no differnce. I'm lost on drive heights once you go to a box - changes everything.......
Finally made a GPS run recently with 27p mirage plus, flat water = 75mph at 5,100 rpm. Slip came out to 12% - better than I thought it would...........Boat ran 76mph GPS at 5,200 with 28p bravo one back in '04.
Now that I have baseline #'s, I'm ready to convert to ?? this winter.......
re-ran the numbers on my old 24 excalibur with nose coned '89 bravo - 8% slip.
Finally made a GPS run recently with 27p mirage plus, flat water = 75mph at 5,100 rpm. Slip came out to 12% - better than I thought it would...........Boat ran 76mph GPS at 5,200 with 28p bravo one back in '04.
Now that I have baseline #'s, I'm ready to convert to ?? this winter.......
re-ran the numbers on my old 24 excalibur with nose coned '89 bravo - 8% slip.
I have a Konrad. Great product. See my Conversion in the Pantera section.
I too get huge roll onto the port side. Bleeds off speed big time.
I tried a spacer and shortie lower, not much change at all.
Email me if interested in teh Konard. I have done the conversion myself and am a dealer for them. I know everyone at the plant.
Kirk
I too get huge roll onto the port side. Bleeds off speed big time.
I tried a spacer and shortie lower, not much change at all.
Email me if interested in teh Konard. I have done the conversion myself and am a dealer for them. I know everyone at the plant.
Kirk
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