Why nitrous guys with 100-150 shots with stock injectors

[MustangLife]

I've been reading around on message boards. I've seen lately some nitrous guys running 150 shots on the stock 19lb injectors. I've seen dynoes in the 400-420 rwhp range. 125 shot guys with the stock fuel pump. But these guys are still on the stock 19lb injectors. I thought these injectors max out at like 320 rwhp. If this is the case and these guys can do this, than why are all the supercharged guys running 30 and 42 lb injectors.

Please chime in. This is kinda confusing me, cause i planned on 24 lb injectors and a 255 pump for my nitrous kit of either 125-150shot? Am I just being smart by upgrading my fuel system.

Thanks
Josh

 

[Red35th]

I think alot of the guys pushing such a high number are running the NX wet kit, which doesn't put as much extra strain on the injectors as a dry. That might be it, I am hoping to get an NX kit towards the summer.

 

[rx7speed]

also something that can make a bit of help is turning the fuel pressure up

this way they can force more fuel into the system
but I don't think it would make THAT much of a difference

would have to check into that


bu as the other guy said prolly using a wet system which in itself puts more fuel into the system

 

[blk2003GT]

I read an article in MM&FF a couple months ago where they put a 150 shot on a '98 GT. They used a second fuel pump right after the fuel filter and they also had a switch to stop fuel from returning to the gas tank, this like doubled the fuel pressure. So thats one way to do it.

 

[StangClear]

Here's good interesting read

http://www.diy-nitrous.fsnet.co.uk/index.htm

 

[Thunder5.0]

That's 320 naturally aspirated with stock fuel pressure. With the NOS you are ramping up the pressure just for the hit. Then it's back to normal. 125/150 is the limit for the stock injectors. Anything over that with the stock injectors then Kaboom!

 

[mogs01gt]

they were probably running a Wet setup.

Wet sprays both Fuel and Nitrous while a Dry only sprays nitrous.

 

[forpit2000gt]

also something that can make a bit of help is turning the fuel pressure up

this way they can force more fuel into the system
but I don't think it would make THAT much of a difference

would have to check into that


bu as the other guy said prolly using a wet system which in itself puts more fuel into the system

you can't turn up fuel pressure on a 99+ and returnless fuel system.
If you run a wet kit, the only strain is the fuel system delivery, not the injectors. the injectors put in what they normally do . the wet kit adds the additional fuel through the TB. I think the stock fuel pump is borderline around 400 rwhp.
I think there are a couple of people that run a 150 shot dry kit on stock injectors, I wouldn't. Unless an 01 or later with 21 lb injectors.

 

[Red2000GT]

Yes I've run the 150 shot a few times with my stock 19 pounders. As long as it's a wet system(fuel and nitrous sprayed together) you are ok to about 400 hp. Much past that and the fuel pump runs out of volume.

 

[blk2003GT]

you can't turn up fuel pressure on a 99+ and returnless fuel system.

I think there are a couple of people that run a 150 shot dry kit on stock injectors, I wouldn't. Unless an 01 or later with 21 lb injectors.

I read in MM&FF "The vacuum line on the solenoids gets activated when the nitrous is armed. It's job is to block the fuel that is being returned to the tank, thus boosting the pressure from 45 to 80 psi. This is where the added fuel comes into play-it is not activated through the nozzle with an additional solenoid." (September 2003, pg130)
So you can turn up fuel pressure on a returnless fuel system. So you can run 150 shot on a 2V with stock 19lbs injectors. 150Shot would be safe on 21lbs injectors??

 

[MustangLife]

forpit2000gt wrote

Unless an 01 or later with 21 lb injectors

Are you sure 01-04 gt's have 21 pound injectors.

Josh

 

[lopey4.6]

you can't turn up fuel pressure on a 99+ and returnless fuel system.

That is plain wrong. On The NOS kit 05116 there is a Electronic fuel enrichment circuit (sort of a BAP) that raises fuel pressure form 50 spi to somewhere around double that.

So in a dry kit you can use 19 lb injectors for at least a 100 shot without running lean and maybe even a 150 shot.

If you up the fuel pressure enough on a 99+ car then 19 lb injectors can easily be enough for 400+ rwhp while on the juice.

This is just specifically for the NOS dry kits.