front mount fuel pressure?

[snowy1]

doe,s anyone know what psi the electic fuel pump puts out befor the regulator. on a cpr kit, I imagine they are all very close to the same. I have checked after the regulator but not off the pump. thanks

 

[Thomas800]

I'm not sure before it, but we have ran 44# after the regulator. I've been wondering about the fuel volume at pressure. I plan to do a flow test at up to 50# to see if we are at the edge with this pump . I don't imagine I will get a chance to do it in time to get you sledders any usefull info but I will post what I find if any of you are interested.
Tom Ljuden R+C Motorsports
www.snowmobiledragsters.com

 

[snowy1]

thanks I would be interested in any info you come up with, I have my fuel line for the nitrous coming of befor the regulator, so I am just trying to figure what size jetting I need for the shot I want. and the fuel pressure will help me figure that out.

 

[givemeaboost]

I run a fuel pump that I got from Alpine when the first started building turbos and they told me it was 125psi, Ken.

 

[Boyko]

If you have a return line to your tank it will be a bypass regulator and it controls the fuel pressure by bleading fuel back to the tank. Pressure in the output shuld be close to the input unless uo got a ton of fuel line. Alpine uses a pump that is compatable with fuel injection and if you dead head it you will see some seat popping high pressure. What kind of nitrous kit ya hookin up I have been thiking about juicing the Vector up

 

[snowy1]

I am running the ice nitrous put it on for the faiview shoot out lat year, it seems to work very well so far. I will check the pressure off the pump maybe today and see what it is for sure.

 

[snowy1]

Boyko: you are right I checked it today, with the bypass its the same as on the discharge of the regulator feeding the carbs I have it set at 3 lbs and thats what it is befor the regulator, that makes a huge difference in fuel jetting for my nitrous set up, I may look at putting another regulator between the nitrous fuel line and the current regulator to up the pressure for my nitrous jetting.

 

[Boyko]

Cool I kind of took a guess on that one. You might want to just turn up your fuel pressure to what the nitrous kit requirers. Your regulator has a boost referance going to it and as your boost climbs so does your fuel pressure. You can make good power by running low fuel pressure with nitrous, not a good idea though. On your nitrous system how do you keep your no2 preasure constant, do you have to heat the bottle?

 

[snowy1]

I don,t use it that often, I plan on just using it to help spool the turbo out of the hole, with the gt2871 I should be able to make enough hp. for most every day riding, when I go to fairview I will run all the nitrous it can handle, I will just try to keep a full bottle for when it really counts.

 

[gsxr]

fuel pressure

Remember guys , alot of regulators will increase pressure but will do it by restricting flow !!!!!

I spent time fighting this this summer on a s/c 600 cu chevy.
more pressure ,yes , but not enough flow !!!

 

[snowy1]

I know the regulator increase,s the fuel pressure as the boost increases, my question is if the boost is 10 lbs and you have your regulator set at 3 lbs at an idle, when you biuld boost you now have 13 lbs, going to the float bowls, but if you are pushing fuel back into the charge tube for the nitrous like I am and the charge tube is 10 lbs. doe,s this offset the pressure from the regulator and still only leave you at 3 lbs. after you have over come the 10 lbs in the charge tube.?

 

[nitrousmudbogger]

yes, if you ran only 10lbs of boost and the fuel pressure was at 3 with no boost reference the boost will likely push fuel back.

 

[snowy1]

yep thats what I thought, thanks