10-17-2007, 01:11 PM #1
Whats fastest you've run.. 14/20 dynafly
7400 rpm rev limiter, how fast can you run before hitting it with stock pitched dynafly 14/20
Also when you hit the rev limiter, does it cut out fuel or spark or both?
I installed a nitrous system on my ski and jetting very conservatively 30 hp (.028 jet) and will test it in a couple hours....
I may not be anywhere close to red limiter, but if i am, I sure hope it doesnt cut out fuel when it bumps it
10-17-2007, 01:17 PM #2
I ran almost 76 on the 1200 with an untouched DF 14-20. I think the rpms were around 7300. It had the 1200 grate and tabs so there is a couple mph right there.
This should be interesting so please let us know the results.
10-17-2007, 01:35 PM #3
10-17-2007, 01:44 PM #4
10-17-2007, 01:45 PM #5
Let us know how it goes. I think I saw some where it cuts spark.
10-17-2007, 01:51 PM #6
Haha well... I will start a thread on my nitrous install if it goes well and I dont scatter my engine across the water.....
Starting very small on jets and will have efi set to 11 for first mash of button Will lean it accordingly. I have a pocket full of jets, so will up the sizes until I get to 7350 rpm. If my smallest jet hits the rev limiter, I downloaded the impeller pitch sheet and printed on clear paper. I can pull pump at river and repitch, but I hope thats not necessary ( or maybe I do! lol)
I plan on installing BB ported cylinders this winter, but figured to do all my testing of nitrous with stock jugs.... Would be sick if I burned up a bb engines testing.... I installed an EGT to be able to monitor things closely.
yeah mrbtd, my initial budget from 2 weeks ago is shot all to heck!
Check out the bottle location... I can remove the mount with pins and install a tube bracket ( for pulling my daughter on ski tube)
Last edited by RUNWME; 10-17-2007 at 02:35 PM.
10-17-2007, 01:59 PM #7
Good luck man. Those Fountain Boys I tell ya.
10-17-2007, 02:03 PM #8
One definite problem you're gonna run into is...
When you mess with the dynaflys pitch....
It either needs filed down OR welded back up to 155mm...!!!!!!!!!
So i wouldn't imagine you'll be lugging welding rigs to the river Bud..??
Now if you had say a 14~20 and selection of others on hand like ~21, ~22 etc., You'd be sorted..!!!
Good luck with this idea...
I'm interested to see how it pans out..
10-17-2007, 02:03 PM #9
I ran a best of 75.3 (75) with a stock 14/20 dynafly on an unported 1200 @7280 RPM.
10-17-2007, 02:06 PM #10
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