I'm considering putting a nitrous express kit on my 305 that has 105,000 miles on it. I have added a afpr and when I check my fuel pressure it drops from 30 psi to about 10 psi in about half an hour, so I may have a leaking injector. Would there be any negative effects if I were to run nitrous? I plan on getting the kit and the gen x upgrade and probably some sort of ignition box. I plan on starting with the smallest jetting and then move up to the 100 shot but probably won't do the 150 shot until I feel really confident with the system. Does this sound like a good idea to you guys or should I consider something else? Thanks.

 

I would not consider putting the N20 on till I found out what was up with my fuel system. Fuel starvation is the number one cause for engine faliure when using N2O. All it takes is one little hicup in the fuel system,and your motor is history.

 

Should you do nitrous? YES.

Should you do nitrous on a dying fuel pump (which you have)? NO

 

Would a inline fuel pump be a good idea.

 

since the auto zone and CSK specials $39.93 only seem to last 6 months and since it is so hard to replace the intank pump in the 1st place I like to use the 255 LPH walbro mustang or 255 LPH holley GM intank pumps. I like the walbros the best.

 

you definately have a fuel issue; must fix that before anything;

your car should be in absolutely perfect running condition if your considering a power adder such as N2O.

there's alot more than that too, you'll need safety elements....some come with the gen x kit. you'll need more.

definately replace the stock fuel pump with a new gm or high performance version. walbro seems to be the choice of most. i went with gm an it works fine. secondly i would recommend adding a fuel pump booster; much like they use with the supercharger kits. it's just an added precaution. don't forget the guages you'll need to monitor everything an you should be good to go.

it's alot of fun for sure, but it's not as cheap as everyone thinks. everything said an done look around 1500 or more if you want to be safe.

 

Let me claify something my fuel pressure drops off from 30 to 10 psi once I turn off the engine this is not while it is running. Is there still a problem? How much should my pressure drop off once the engine is off?

 

so when your car is on at idle it's at 30?

when you shut it off the guage goes to 10?

sounds like something is definately wrong.

mine goes back to it's flat 0 position......all the way left or right, can't remember it's been so damn long since i've driven her.

the guage itself should be at the lowest resting point unless your engine is "primed"

ex: if i turn my key forward when getting in the car the guage will go to 42, when i turn it over it will flutter a bit a zip back to 42 until i go to step on it then it will go up. basically this is the normal way it should work (of course in lower numbers for you.)

 

Yes it goes down to 10 after I turn off the engine and after about half an hour of waiting. This is on a hypertech guage hooked up to the schader valve. It sounds like you have a guage in your interior, am I right?
So what other things should I check on my car? Does it sound like my car will be able to handle a 75-100 shot?

 

no, not from the sounds of things......you need an accurate fuel guage; a perfect running fuel system an your engine should be in good running shape.

any slight problems in any of this an you'll be shopping for a new engine.

if your engine runs like a good shape engine should and your fuel, ignition, etc. is in great condition then go for it. i would start low though an work up to the 100 shot......some go over but they also get lucky.

 

kandy.. what inline booster are you running?

I'm got a walbro 255 in my GTA, and it seems to be holding up fine.. but I"m about to finish my dual stage setup, and want a little more security.

 

i looked at quite a few and finally went with an ati booster, they commonly include it with their supercharger kits or you can buy it seperately; since i had planned on buying the kit an need one anyway i bought it. it works perfect; it's very quite too...supports more power than most of us will ever have to worry about. not to mention i'm running just an upgraded gm pump, so it's not some special aftermarket version.

i'm very happy with it!

 

Why do you say my guage is not accurate? My car seems to be running perfect and when I hook up the guage and drive it the pressure stays a steady 30 when ideling and increases to around 42 at wot. From what I see my fuel system is running good when the car is driving it just bleeds off after about 10 minutes once the car is turned off. Is there anything else I should check out? Thanks.

 

ttt

 

couldn't tell you......any fuel guage i've ever seen drops back to its "resting" position, never seen one hold a fuel pressure except when you just turn the key forward and prime the pump.

 

are you disconnecting your vacume hose from the regulator when your getting these readings?

 

The 30 psi reading is with the vacuum hose disconnected at idle. Then once I shut my car off it drops to 10 psi after about half an hour.

 

Stock is like 43 psi so id say you got problems and to fix em before you even think about looking at a bottle

 

Sorry I meant to say that the pressure is at 30 psi with the vacuum hose connected and 42 psi with the vacuum hose disconnected. Then when I shut the car off with the vacuum hose connected it drops to around 10 after about half an hour.

 

there is an anti backflow valve in front of or inside the pump on some of these cars to reduce the amount of crank to start time for priming, your is probably leaking back no big deal but sometimes it is a leaking or stuck injector that causes the pressure to go down fast. some cars just do and others dont, I'm not sure how critical it is.

 

Ok theres a big diff I say if your running 42 diconnected then your fine. Go get your bottle. The fuel dropping a few psi in half an hour is no big deal. now if its dropping in 2 mins then theres a problem

 

Thank you that is what I wanted to hear. I am going to change my spark plugs and make sure my ignition is in good working order. Is there any other things I should do before I get my kit?

 

Just learn as much about nitrous as you can and make sure your fuel pressure isnt dropping when you go into wot on the bottle.