Viper 640 PHRF

[Thomas Leith]

It is basically impossible to rate a Viper fairly versus a boat like the J-29 -- the designs are just too different and they ought never be raced in the same division. Sometimes though it is impossible to run them in different divisions and we just have to accept the limitations (or not race). The best we can do in our part of the world is use the Melges 24 as the reference and try to rate "similar" boats like the Viper and the Melges 20 versus the "well accepted" rating for the Melges 24. It seems to us the Viper 640 should rate somewhere around Melges 24 + 9. Here's another criterion: if six seconds a mile would make a big difference in your SEASON you might have grounds for an appeal of your rating. Anything more than that: shut up and go sail and be glad you have something resembling a competition.

Lake Michigan is rating the J-80 at 114 base and it is a 26 footer. In lighter air I think it'll waterline a Viper to death. In medium air things should even out some. In heavy air, it is all about boat handling and to some extent anyway the rating goes out the window.

[David Furna]

In NC, I started with a 90, same as a M24...after 2 years I appealled and was give a 96. I don't like it but it will do.....

Type of course makes a difference....some area's do modified Olympics or even a triangle. All I get are W/L's....

[Jason Hyerstay]

Hey guys, I'm reviving this thread.

I'm about to submit a fresh PHRF form for my next Viper, and I don't think I have all the measurements that they want. We already have a rating from the other Vipers on the lake, but I'd like to get this all this data if possible. The length and displacement and such are on the site, but I don't know where the class or Rondar list the other dimensions.

http://www.mbbc-vt.org/phrf/PHRFForm.pdf

Thanks,

jason

[Drew Harper]

Hey guys, I'm reviving this thread.

I'm about to submit a fresh PHRF form for my next Viper, and I don't think I have all the measurements that they want. We already have a rating from the other Vipers on the lake, but I'd like to get this all this data if possible. The length and displacement and such are on the site, but I don't know where the class or Rondar list the other dimensions.

http://www.mbbc-vt.org/phrf/PHRFForm.pdf

Thanks,

jason

TC guys should have the various IJPE, prod, etc.

Your sailmaker has your girth measurements ;-)

[Craig Wilusz]

Here are measurements from our current Gulf Yachting Association (GYA) PHRF Certificate:

Note: Measurements in feet

Sprit 14.3 (this is a "extended J measurement" if you will, not acttual sprit lenght)
LOA 21.08
LWL 19.08
BEAM 8.17
J 8.03
I 21.82
ISC 24.45
P 25.62
E 10.0
LP%J 102
Spin Luff, 31.89
Spin Leach 23.95
Spin Foot 19.19
Max Girth 18.04
Sq Foot Genoa 87sqft
Sq Foot Spin    425sqft
SA/DSPL Ratio 51.1

We rate 102 in GYA PHRF, our Hobie 33 rates 99.
A Melges 24 rates 96

GYA PHRF site if you wanna compare numbers: http://www.gya-phrf.com/

On average it seems the Viper should rate around 6-9 seconds "slower" then a Melges 24. 

On a side note the GYA uses recommended crew # / weight limits for key events.  Funny that our Viper640 Max crew limit is 7 / 1260lbs

[Jason Hyerstay]

Thanks Craig!

For this form, I still need:

ISP (Spin halyard height)
ASMG (Asymmetrical mid-girth) - is this the same as max?
BS (Bow Sprit Length)

And I already emailed Dave N about this, but what year would #18 be?
Oh, and who/what is the "Make" if the "Model" is Viper 640?

Thanks!

jason

[Jason Hyerstay]

Ok, I got some more numbers from Dave N.:

ISP = 24.05
ASMG = 18.05

And I figured these out from the rules

BS = 6.23
LP in feet = 7.22

I think I got it!

[Craig Wilusz]

I goofed

Our Viper Rates 96
Our Hobie 33 Rates 99

Melges 24's around here rate 93

[David Furna]

96? thought you guys got a 102 gift last year? I was moving to Florida.....

Melges are 90 in NC, Vipers 96

[Thomas Leith]

With the M24 @ 93, the Viper @ 102 is the midpoint of the reasonable range of deltas -- we think Vipers should rate 6 -- 12 seconds slower than the M24, depending on locale (wind & sea states typically seen) and assuming they race in the same division. If you get a rating anywhere in this range it is "fair enough" to go have a good time. And I reiterate what I said about this last September. Don't be a whiner, go sail and have fun.

[Jason Hyerstay]

What region has the 81 rating? I spoke to my local rep, and he quoted our range as 81-111, and that 81 really drags down the average.

jason

[David Furna]

That's a Viper that was highly modified down in Charleston years ago. My local PHRF uses that as a low number too and I call BS on it. I don't think the boat sails anymore, but it's rating lives on.

Legend has it that boat was so overpowered that only some of those Texans would try to sails it.....JJ would for sure!

[Jason Hyerstay]

Does anyone have a PHRF contact down there? Can we just have it removed from their database and let any new owner apply from scratch with proper details?

BTW, here is the PHRF form I submitted, minus my address info:

[Justin Scott]

What region has the 81 rating? I spoke to my local rep, and he quoted our range as 81-111, and that 81 really drags down the average.

jason

We have spoken to them, written to them, spoken to the preparer of the PHRF handbook to no avail.  The Viper in question had a traveller, a taller custom carbon mast, oversized sails etc.  It has been retrofitted to One Design and is part of the fleet again but Charleston judges Vieprs on that boat. Feel free to have another go. Meanwhile most of us just tell our local PHRF cttee that it was not a Viper and ask them to drop it out.

[Michael Gravitt]

I started at 96 and filed an appeal had it changed to 102. Had to jump through a lot of hoops but they agreed.