Zman420

iTrader: (18)

First off, if you are one of the ones that likes to run race-gas for you nitrous but your engine feeds off the pump, this is not the route to take.. You would be better off just getting a seperate tank to run the "nitrous fuel". Although you could still use this same idea, but thats up to you..
I have known the old school guys to run their seperate fuel supply units closely related to this setup, and being the poor *** kinda guy that I am, and not really trusting the aftermarket pumps (Iv had and seen many fail under nitrous), this is the route I chose.. It's not for everyone, but so far it hasnt given me one problem thus far.

Second off, I built this system more then a year ago and cant remember the size fittings I used or the part numbers for that matter, but I basically walked into "Smiley's" here in houston and stood in front of the nitrous fitting section for a good hour or two and pieced it all together and shouldnt be that hard for one to duplicate it..

First I made the pickup tube by measuring from the top of the tank to the bottom, and cut a piece of 3/8 alluminum tubing to about 1in. or so less then that dimension and flared one end of it. I wrapped the end of it in teflon tape and slid the little flaring fitting over it.
It should look something like this (minus the an fitting on the bottom, thats in further steps)


I then made the Inlet for the pump to feed off of by taking the elbow, wrapping both ends in Teflon tape, sliding a 1/8in. or so thick metal washer on it first, followed by a Rubber washer to aid in sealing. There should be another rubber washer on the bottom, (that will go on the inside of the tank) followed by another smaller O.D. diameter 1/8in metal washer, then a nut to sandwich everything together!
I used red RTV on both rubber washers to insure no leaks from air or fuel (but DONT RTV anything yet).. you still need to pre-fit everything!

It should look like this.. (The picture isnt that good and and you can only see the nut at the verry bottom of the assembly).


Here is both pieces assembled together. (now we use that big nut on the bottom to slide over the flared coupling to attach the two pieces together)
This is just some "pre-Assembly"


Now here is where it gets scary! lol you only get one chance at this, so dis-assemble everything you have made thus far exept for your elbow and top rubber and metal washer and measure, measure, measure!
You basically want your hole to be where your pick-up tube is going to be in the rear most of the flat bottom of your tank.. You also have to watch out for where the top Inlet is going to be, becuase it's going to cut it pretty damn close to the top of your stock pump assembly is..

This is where I drilled mine using a 3/4in. hole saw bit.. (If you are not confident with drilling at this point, stop and recheck every measurement, smoke a couple cigs, and re-attempt.)


Ok! relax, and prey you didnt get it off the money! (or you will be buying a new gas tank)

Now you can Pre-fit everything back together, take your upper half of the elbow/inlet and slide it down into the hole you just drilled, and slide your bottom rubber, metal washer onto the elbow inside the tank and thread your nut on kinda tightly.. (DONT use RTV at this point! you are still pre-fitting!)

Then take the bottom (pickup tube assembly) and assemble and thread onto the bottom of your inlet assembly..

It should look something like this...(It's kinda dark in the tank so you cant hardly see the pickup tube in the pic)


Now for the moment of truth! Install your factory sending unt/pump assembly into the tank and pray once again that everything clears! If it goes smoothly you should have something like this!

(Note how close the damn sending unit retainer is to your Inlet!) scary ****!

Now that you made it this far, before you go RTV'ing the rubber washers and fully tightning everything up, its a good time to connect you 3/8in. I.D rubber fuel line to you inlet and the other end to your external pump.
(I used a low pressure "HOLLEY BLACK PUMP") It's basically just a old low pressure carburator external pump that will flow more fuel then you will ever need! (You can change the spring in it to make it low or high pressure) wich in this case, since its feeding our nitrous, We need the low pressure!

This is what you should have thus far:


Now it's time to test everything out! hook the holley pump up to a battery and watch this badboy soak your driveway in a matter of seconds! lol


Once your satisfied with everything, its time to dis-assemble everything you have done this far, and (NOW you can RTV your rubber washers "both sides" and tighten everything back up so your 100% sealed on both the inside and outside of the gas tank)

Now that everything is back together and sealed, route your fuel line along side your factory fuel lines using zipties and install the gas tank with your fuel line hanging down.. make sure nothing gets binded or pinched..
Mount you pump as close to the tank as you can wherever you can find a spot..(I tack welded a bracket on the back side of the body behind the back seats) BUT BE CAREFUL and check to make sure that the rearend and suspension can go through full travel and not hit any fuel lines or your pump for that matter!
Also, BE CAREFUL if you are going to weld on the back side of the body behind the back seats that you DONT penatrate too far through the metal.. It's verry thin and you will do like what I did and start a small fire on the back carpet underneath the back seat!! again...SCARY ****!

Once you have the pump mounted find a spot in the engine bay to mount your Fuel pressure Regulator and run your fuel Line up to it (avoiding the headers) wrap alot of some sort of insulation around the fuel line to cover it going up through the engine bay! (it will be somewhat close to your headers!)ALSO, it's a good Idea to run a in-line fuel filter somewhere along the way!

Here is where I mounted my FPR and FPSS:

(the pic dosnt show the fuel line routed up there to it yet, but you get the idea)

From here out, wire everything up, Adjust you FPR and FPSS accordingly and mount a button somewhere in the cab so you can turn the pump on.. (or do like I did and wire the pump into to the main nitrous switch so that you cant turn your solenoids on without turning your pump on) Becuase that would really suck!

All in all I probly spent less then $200 on everything and it's a damn solid working system!
You will need approx. 15ft. of 3/8 fuel line to run everything up to the FPR.
PM me if anyone has any questions regarding this.. I might of left some things out here and there but its like 5am in the morning and Im going to bed regardless! lol

Lonnies Performance

iTrader: (16)

After using low pressure carbed style nitrous systems for a long time, I am going to make a few recommendations.

First, RTV is not supposed to be used in direct contact with gasoline. It can soften & I have seen many brands actually dissolve when submerged in gasoline. You should use a stato-seal under the bulkhead nut or at minimum find a fuel proof sealer to use in the tank.

If you have a car that launches rather hard, the G-forces in the fuel line can overload the in-pump relief valve & cause a sharp fuel pressure drop when you leave the line. Lean backfires are not pretty. My car would go from 7 to 2psi when I launched the car. To help combat this, use the high presure spring in the pump & always run a front mount regulator. Do not depend on the fuel pump to properly control the pressure.

Zman420

iTrader: (18)

Thanks for the recomendations! Although, I DO run a Regulator (pictures) and is set at about 12-15psi and the SAFETY SWITCH set at 10psi and yet to have any backfires, or fuel cut..
That is why it is VERRY important to run a safety switch no matter what kind of system you are using!
I will keep that in mind and maybe step it up a little by changing to the high pressure spring one day if I ever run into any problems...So far, nada.. Thanks for the input.