doesnt your dedicated system use the walbro 225 and 3/8" lines?
If so how will it support those levels.
If not what pump and line size does it use

 

The walboro pump we use at 13 1/2 volts and 10psi is flowing 85 gallons ph. With the math suplied by the manafacture this shows the system can support up to 1190 hp.

And at 13 1/2 volts and 45psi it flows 67 gallons ph. The manafactures math shows the system can support up to 938hp..

At 60psI and 13 1/2 volts it flows 50 gallons ph. The manafactures math shows the system can support 700 hp.

We supply -6 hose and fittings. The hose has a larger orfice size than the pump so there will be no problems there.


Keep in mind this is MAX flow!!!
Dave

 

You may be missing the point I was trying to make, not trying to discount your advice/input. I was clarifing the need for a return and reg on any high perf application.
Did the car that maxed out at 650hp have the return and reg at the rails?

Here is the dedicated we offer. 3qrt and can handle upto 1000hp with upgrade pump, comes complete, even has a flow port for tuning.


Robert

 

Robert,
How much of a gain is there in swaping from the stock fuel rails to the 97/98 style fuel rails with the return? Why is there a hp gain if any from doing just this? I have the 97/98 style fuel rail set up in my 94 that I did the LS1 swap on. I have heard of some of the corvette guys doing this but im not sure I understand what the big advantage is.
Thanks
Dave

 

The advantage, really for us sprayers, is stable fuel pressure/supply. What's happening is when at highest demand, the rails drain and pressure drops, sometimes as much as 15lbs or more. This leads to leaness. The reason this is happening is because the reg at the tank, it first senses pressure drop late, then makes adjustment, then it takes a bit for supply and demand to reach the rails once again. this can lead to lean spikes on intitial hit, and/or at the highest demand. It's not so much that it adds any hp overall, but rather allows the system to support a higher hp than it could without, and safely. Racetronics even suggests doing this, and has a kit for putting the reg and return at rails for the f-bod guys (but you can still use the 97/98 vette rails), but not out yet, it's on their site. Other companys (MDMC) also offer kits but they cost big $$. I have done this to my car, and have eleiminated the lean spike on activation alltogether, and it does not drop in psi at 250rwhp shot with both stages activated. You can make this system even handle more hp if you use the existing supply line for the return, and add a 8an line for supply. There is even an adjustable pressure reg for the vette rail (stock is set at 58psi and not adjustable). Why GM didn't stick to this set-up is often speculated, but most think is was mostly a $$ cutting thing.
Robert

 

I can see how haveing the regulater and return may help slim down the chances of a lean spike for someone stretching the limits of there fuel pump. I just do not see how it would overall support more HP from a flow stand point than haveing the factory style setup.

This may be what you are trying to say. I may be reading it wrong...

This part of what you said above confused me. "It's not so much that it adds any hp overall, but rather allows the system to support a higher hp than it could without"

Dave

 

Look at it this way, say the pump can handle 650rwhp. Ok now, your system connecting to the pump allows a 15psi drop in pressure at the highest hp, how can it safely still handle the 650rwhp? NX has the accumulator, which fixes this type of problem. I have mucho links if ya want more info on this. All the big HP vette guys do this, as it's really the only way to sustain high hp and keep the pressure up. What happens to the injectors when they should have 58psi and now they have 43psi. If ya regulate at the rails, it's instantanous, rather than having lag time, or flat not able to keep up. A good test for needing this is watch your psi at highest demand, if your dropping pressure, this will cure it.
Robert

 

Ok,
I see your logic and have seen people doing it. So I now understand what some peoples thoughts are.

Here are my thoughts.
If you are running into that problem its because there is not enough pump to keep up with the volume demand. I have used the fuel accumalater for a few customers on there NXL kits. I know it works but is a band aid. I would not use it to aid a fuel supply problem.

I feel that if you are haveing that much fuel pressure drop you may be able to aid it by adding the accumulater but all you are doing is band aiding a problem and working the pump to death. The best bet is to go to a better pump that can handle the volume demand.

The only down fall is that in some applications there are not alot of options to upgrade the fuel ssytem with out tying up some serious cashflow. Luckily the wet nitrous nitrous guys can just add a dedicated and have the best of both worlds. The guys running dry systems will have to set there fuel systems up like a supercharged or turbo application. Depending on the hp levels they may need to go to a real pump set up like aeromotive.
Dave

 

Ok that helps me alot on my part so i have a question that didnt get answered, what injectors should i use (keep in mind this is on a l76 intake) for my first stage considering that will be the only one coming off the fuel rails. I should be somewere around 700rwhp on the first stage and will be using my stand alone for the second stage.

 

If you are running both stages wet injectors will not matter as long as you have enough injector to support the motor. Why not run both stages off the dedicated?
Dave

 

Well i guess i could there wouldnt be no problem with that im still wondering what size injectors i would need then tho.

 

Here's the math fo inj.
(projected bhp x .5) / 6.4 = min inj to meet 80% DC rule

The bhp is n/a hp, and only include n2o dry hit hp if going dry.
Robert

 

Ok looks like it came out to be 37lbs injectors. Using a wet kit there will be no need to use bigger injectors to keep up that large amount of nitrous right?

 

Right, select injectors for n/a needs.
Robert

 

Robert, why wouldn't you just use the dedicated for both stages? Surely the pump would support 400 horsepower and you would still not use a gallon of race gas in a quarter at only 400 horses? Wouldn't the race fuel in the standalone also be extra insurance also?

I'm confused...

 

I also wondered that but he knows alot more than i do. I still would like to see what he says.

 

You can use the stand alone for both if ya like. Just giving some options. If you were to run a BAP with the above fuel mods you could even support a higher hp. Changing to reg and return at rails cost me about $300, so it's just another idea for those that aren't going mega hp.
Robert

 

Since you are installing a dedicated I would go ahead and run both stages off the dedicated. This way you do not have to worry about starving the fuel system.

But the biggest perk is that you can run pump gas in the tank and 116 or 118 in the dedicated to bring up your over all octain level when spraying.

Everyone has there own ways of doing things. This is how I would do it..
Dave