universal nitrous question

[95lt1impss]

i just got this car so bear with me. i got a bone stock lt1 95 impala ss and was wondering if these motors had fuel return lines or were they returnless? i'm asking this b/c i have a universal NOS nitrous kit lying on the side that i'm planning on installing. I've read that the lt1 even in stock form can take a 125 shot... I'm only planning on only using a 75 shot. But yeah was just wondering for future reference. Thanks in advance.

[95lt1impss]

anyone?

[Grims]

What is it you are asking? Are you trying to figure out where to tap into fuel?

[95lt1impss]

What is it you are asking? Are you trying to figure out where to tap into fuel?

basically yeah. where to T tap the vacuum line so when the nitrous engages, it begins to raise fuel pressure.

[01Z]

If you are using a wet kit you will remove the cap from the fuel rail, unscrew the schrader core and use a -an 4 connector there. That access port can be easily seen by going to http://www.shbox.com and browsing through his site. It won't be hard to find.

The 95 has a return side to the fuel rail btw.

Tell us more about the nitrous kit please....

[95lt1impss]

If you are using a wet kit you will remove the cap from the fuel rail, unscrew the schrader core and use a -an 4 connector there. That access port can be easily seen by going to http://www.shbox.com and browsing through his site. It won't be hard to find.

The 95 has a return side to the fuel rail btw.

Tell us more about the nitrous kit please....


its a universal dry NOS nitrous kit. it taps into the intake piping and adds more fuel by mean of changing the vacuum levels goin into the fpr.

[vernw]

That sounds like the NEX kit

[01Z]

its a universal dry NOS nitrous kit. it taps into the intake piping and adds more fuel by mean of changing the vacuum levels goin into the fpr.

The way I thought I understood how a single solenoid dry system works is the MAF gets the blast of nitrous and the drastic change in temperature signals the computer to add fuel. As for the fuel pressure regulator adding more fuel, this I also thought, is the same with wet or dry systems. The open throttle drops vacuum and the regulator goes to a setting that increases fuel rail pressure. I know on my LT1 it is an increase of 4-6 lbs.

[860]

Ther are 2 popular dry approaches, MAF and Fuel pressure boosting. The MAF approach works great with LS1's but not LT1's. The LT1 MAF / computer dosen't compensate for fuel like the LS1's.

The dry kit you have with the line for the regulator is the right kit for LT1's. Just hook it up to your regulator.
The only concern is the fuel pump. NOS includes an upgraded pump when running that style dry kit for LT1's, since it needs to run at higher pressures.
I've never tried to find the limit on an LT1 dry kit with a stock pump.
You have 2 options:
1. Play it safe and get a pump.
or 2. try it on a dyno and figure out what the stock pump will do.
Vinny

The way I thought I understood how a single solenoid dry system works is the MAF gets the blast of nitrous and the drastic change in temperature signals the computer to add fuel. As for the fuel pressure regulator adding more fuel, this I also thought, is the same with wet or dry systems. The open throttle drops vacuum and the regulator goes to a setting that increases fuel rail pressure. I know on my LT1 it is an increase of 4-6 lbs.

[01Z]

I know you are right but I haven't gotten how the dry system works without going through the MAf.

A dry system that has no connection to MAF confuses me because without the computer adding to the fuel injector pulse width the air / fuel ratio would be no different than WOT any other time. The only way a greater amount of fuel would be added is with a different fuel pressure regulator and tuning to allow more than 43 lbs for the LT1 if no manipulated maf signals are involved.

I probably did wrong by going with a wet system for my 95 but I did add a 260 gph in-line pump to the stock system. I have seen 9 degrees of spark pulled and an alarming .078 narrow band reading at open throttle for a moment. I have since added an Innovate LM-1 and LMA-2 but no opportunity to test now.

[860]

All they do is jack fuel pressure way-high. So when your injector opens more fuel flows through it. As you can imagine its tough on the fuel pump, but they work for small shots.


I know you are right but I haven't gotten how the dry system works without going through the MAf.

A dry system that has no connection to MAF confuses me because without the computer adding to the fuel injector pulse width the air / fuel ratio would be no different than WOT any other time. The only way a greater amount of fuel would be added is with a different fuel pressure regulator and tuning to allow more than 43 lbs for the LT1 if no manipulated maf signals are involved.

I probably did wrong by going with a wet system for my 95 but I did add a 260 gph in-line pump to the stock system. I have seen 9 degrees of spark pulled and an alarming .078 narrow band reading at open throttle for a moment. I have since added an Innovate LM-1 and LMA-2 but no opportunity to test now.

[01Z]

All they do is jack fuel pressure way-high. So when your injector opens more fuel flows through it. As you can imagine its tough on the fuel pump, but they work for small shots.
Vinny, how does the dry system increase the fuel pressure without a secondary pump and wouldn't the stock fuel pressure regulator override any boost in pressure? Sorry for being ignorant here.

Thanks

[860]

They only work on cars that have a return style regulator(TPI and LT1's), with a manifold pressure reference. (the vacuum line)
What you do is cut the vacuum line to the regulator, and then spray some regulated n20 into the regulator. It spikes the fuel pressure that way.
Make sense?
Vinny
Vinny, how does the dry system increase the fuel pressure without a secondary pump and wouldn't the stock fuel pressure regulator override any boost in pressure? Sorry for being ignorant here.

Thanks

[01Z]

Ah, okay. Since a wide open throttle drops the vacuum and closes the return side, sending pressure into the vacuum side via the n2o apparently closes the return side even more completely and forces the regulator to allow greater pressure in the fuel rail. It would seem that method would put an inverse load on the fp diaphragm. Making me wonder if that might shorten the life of the regulator. Thanks for the explanation.

[Helmsdini]

It definatly stresses the regulator. I have seen a ton of stock 5.0 regulators burst and fail when using dry systems. I run an accufab in mine and it has been great for about 4 years of abuse.

[juanitowieler]

01Z why would you rather have a dry kit instead of a wet kit?

[01Z]

Hi and welcome to the forum.

I don't own a dry kit and was only asking how they work. I know that Zex has a dry kit for the LT1 but I bought a wet kit (for the LS1) and added an in-line fuel pump to boost fuel volume. I think I was misunderstood.

[juanitowieler]

Thanks and sorry for the stupid question:banghead:

[01Z]

Thanks and sorry for the stupid question:banghead:Not a problem. It helps to boost my post count. :lol:

[juanitowieler]

Not a problem. It helps to boost my post count. :lol:
well at the rate im going its probably gonna take me a year to get where u are

[maverick95z]

Can you tell me what nitrous kit is the best for a street mild bolt on lt1 z28?

[01Z]

That's an often asked question with a huge field of experts to answer it. ;)

Hopefully a sponsor will contact you as a simple answer isn't what you really want. You can buy expensive solenoids and cheap switches. All the bells and whistles or a simple button hooked to a solenoid, lines, tank and a fogger. Choosing safety and economy is a balancing act.

[94firechicken]

Im gonna use the button hooked to a solenoid lines,fogger and bottle procedure..Im just so cheap after losing my ls1.

[Grims]

I went super cheap when I started mine. Solenoida, bottle, button. From there I progressively upgraded it. First I got a retard box and window switch, then a bottle heater and so on.

[94firechicken]

I run an auto, i believe i can contoll the n20 via the button for the 75 shot i plan to run,anything bigger ill get some safety stuff,which is dirt cheap also,just an install hassle....