snoprokidf6
Member
Looking to break out my viper onto the water for some drags, potentially ovals. Any ideas on sum jetting for a stock engine with CPR pipes?
ive searched, and searched and searched, even googled, absolutely nothing. Figured some guys who grass drag would have some info for me.
thanks
Nick
ive searched, and searched and searched, even googled, absolutely nothing. Figured some guys who grass drag would have some info for me.
thanks
Nick
YAMMIEGOD3:16
Active member
whats in this for winter ? should be around 160s ? or alittle less. 3:16x (yammie tony)
Mac
Member
This is a loaded question. Getting the data setup sheet from Simons is no big deal. i will look for mine and see if i can post later. As Tony said 160ish for mains would be the winter set up. But pilots and needle, nozzel, fuel, lots to be considered. Your tuning abilities will be tested. You might want to PM MrViper700.
YAMMIEGOD3:16
Active member
these were very good pipes. get this right. 3:16x (yammie tony)
snoprokidf6
Member
160, 160, 162.5
I believe I have 47.5 in it for pilots
I've tried contacting simons..... Nothing
I was thinking about dropping two or 3 mains and a couple pilot sizes and going from their
I believe I have 47.5 in it for pilots
I've tried contacting simons..... Nothing
I was thinking about dropping two or 3 mains and a couple pilot sizes and going from their
Mac
Member
Back when I had was able to enjoy the riggers of grass dragging, my rule of thumb was dropping down 1 jet size per 20 degrees ambient temp. As for jet sizing, that was using the hard to get and expensive oem mains as they are available in different increments from oem than aftermarket. Use an oem jet chart for a baseline and adjust for the pipes.
For the pilot circuit, you will want to actually decrease the adjustment screws by about 1/8 turn per 20 degrees and adjust your needle setting by half increments up to about a #2 position setting. Have your shims ready to make changes. Not too sure on water, but on grass, your going a specified distance and you can easily add fuel(to cool) at the end of the run by burping the throttle. If your setting lean for distance runs on water, your going to be blazing your own trail there to a certain degree.
As with any non traditional usage for your sled, you have to test and tune. Carbs are only part of the equation, you need to think clutching as well as temp and humidity affect that equation as well.
For the pilot circuit, you will want to actually decrease the adjustment screws by about 1/8 turn per 20 degrees and adjust your needle setting by half increments up to about a #2 position setting. Have your shims ready to make changes. Not too sure on water, but on grass, your going a specified distance and you can easily add fuel(to cool) at the end of the run by burping the throttle. If your setting lean for distance runs on water, your going to be blazing your own trail there to a certain degree.
As with any non traditional usage for your sled, you have to test and tune. Carbs are only part of the equation, you need to think clutching as well as temp and humidity affect that equation as well.
YAMMIEGOD3:16
Active member
don,t have a heart attack, and i don,t recommend this, but according to my mikuni pocket tuner at sea level and 75 degrees you can go down 10 sizes on your mains vs your winter jetting and be jetted for top performance. 150 - 150- 150. 3:16x (yammie tony)
snoprokidf6
Member
Thanks gents
staggs65
Moderator
I had to go up in pilot size for my piped viper to not fall on it's face off the line on grass. But that might not be the case for water, never ventured there.