Shot of NO2 to spool turbo

[spoolinhard]

If I need a shot of nitrous to spool a larger turbo, where would I install the nitrous, and what size shot do i want to use? I would imagine 30 shot nitrous?

[contraption22]

A 30 shot will do amazing things! It's about the minimum right you can run with 55psi of fuel pressure. Cut my 60 ft but about .15 seconds. I installed the nozzle in my upper intercooler pipe about 12 inches from the throttle body.

[spoolinhard]

A 30 shot will do amazing things! It's about the minimum right you can run with 55psi of fuel pressure. Cut my 60 ft but about .15 seconds. I installed the nozzle in my upper intercooler pipe about 12 inches from the throttle body.

Aha! Thanks. I was told that I should install the nozzle into the compressor housing.

[BadAssPerformance]

30 shot is for babies

How big of a turbo is this? drag car? just leave HARDER!

[spoolinhard]

30 shot is for babies

How big of a turbo is this? drag car? just leave HARDER!

Pretty much drag car, other than the fact I am going to be keeping full interior.

Turbo= T04 housing Garrett .60 A/R compressor side, .81 exhuast.

[contraption22]

Pretty much drag car, other than the fact I am going to be keeping full interior.

Turbo= T04 housing Garrett .60 A/R compressor side, .81 exhuast.

Wow..... wouldn't hurt to get a variety of jets, just in case you need more

[Ondonti]

ive heard of 20 shots on 900hp cars. Increasing torque over 90ft/lb from spooling earlier. They actually turn the nitrous off once the turbo spools.

[zin]

Lots of good info there guys, nothing I can disagree with. With respect to a 20HP shot on a 900HP engine, they would have to be running a stand-alone ECU in order add such a small amount. The problem is the fuel pressure and the fact that the smallest practical fuel jet, @55PSI, will allow around 30-40 HP worth of fuel in, so while you could jet the nitrous side smaller, all you would accomplish would be a very rich mixture, and the poor performance that goes with it.

It is also fairly common to use a "boost cut-off" switch that kills the nitrous once approximately 1/2 max boost is reached (often in just a second or so), in order to spool up a turbo that would otherwise be laggy until higher RPM where the engine is making enough exhaust to run the turbo by providing a healthy dose of exhaust where the engine wouldn't normally have it. The switches themselves are simply a normally closed switch that breaks contact at a set pressure, the ground for a relay or the solenoids themselves are normally connected to this switch.

Mike

[Ondonti]

Those guys run more like 40psi fuel pressure.
And it might be a dry shot.

But I am pretty sure you can buy 15hp jets. People do direct port setups afterall. Most people here dont run 55psi on bigger injectors anyways. I certainly wouldnt. Poor fuel pump. 85psi fuel pressure at 30psi =

[contraption22]

Those guys run more like 40psi fuel pressure.
And it might be a dry shot.

But I am pretty sure you can buy 15hp jets. People do direct port setups afterall. Most people here dont run 55psi on bigger injectors anyways. I certainly wouldnt. Poor fuel pump. 85psi fuel pressure at 30psi =

Direct port systems are rarely jetted for less than 100hp on 4cyls, and usually they are run with a completely independent fuel system from the regular induction system (the N20 system would have it's own fuel pump, lines, and regulator, sometimes it's own fuel cell.).

[Ondonti]

Direct port systems are rarely jetted for less than 100hp on 4cyls, and usually they are run with a completely independent fuel system from the regular induction system (the N20 system would have it's own fuel pump, lines, and regulator, sometimes it's own fuel cell.).

You are talking about what is often done, not what "must be done"

There are a LOT of nitrous companies out there too to get parts from too.

[8valves]

It works really well. On some of the cars I've used it on, it's either a direct port with smaller jetting running all the way through the pass, or at the TB inlet to the intake for a larger hit until a predetermined point. Both work really well, and are addicitive.

On the downside it is one more thing to worry about from run to run.

[zin]

You are talking about what is often done, not what "must be done"

There are a LOT of nitrous companies out there too to get parts from too.

What "must be done" is to balance the lb/hr of nitrous to the fuel. If you want to do a low HP set-up, you will have to run a low pressure fuel system in order to keep the fuel flow down to the HP level you want to run, there are some very small jets available (.008"), but I've never been very comfortable running a jet with a hole smaller than a human hair! Especially on the fuel side! Most guys would be running a single nozzle style kit, and at the (base) fuel pressures we run, the smallest combo would be about 40HP (34nitrous/18fuel) and even that fuel jet is probably going to be a bit big the combo is meant to be safe on a 40PSI system. Another factor in the HP calculation is the unknown HP increase that the added intercooling effect will have, that can vary from almost nothing to damn near 2X the power! Most of the time it is in the 20-40% range.

Any way you skin the cat, you have to balance the nitrous fuel ratio, which incidentally is ranges from 5-6:1 nitrous to fuel (lb/hr) with most tune-ups set to 5.5:1.

Contraption has a pretty good handle on this stuff from the info he's shared, IMHO.

Mike

["Top Fuel" Bender]

there are some very small jets available (.008"), but I've never been very comfortable running a jet with a hole smaller than a human hair!

Not to split hairs but the standard on hair thickness on the east coast is usually .007"
I'm currently trying to stay away from the dark side but it is VERY tempting
but also seems very addictive
I have to hypnotize myself before I get in the car not to touch the manual boost controller while going down the track

[Ondonti]

What "must be done" is to balance the lb/hr of nitrous to the fuel. If you want to do a low HP set-up, you will have to run a low pressure fuel system in order to keep the fuel flow down to the HP level you want to run, there are some very small jets available (.008"), but I've never been very comfortable running a jet with a hole smaller than a human hair! Especially on the fuel side! Most guys would be running a single nozzle style kit, and at the (base) fuel pressures we run, the smallest combo would be about 40HP (34nitrous/18fuel) and even that fuel jet is probably going to be a bit big the combo is meant to be safe on a 40PSI system. Another factor in the HP calculation is the unknown HP increase that the added intercooling effect will have, that can vary from almost nothing to damn near 2X the power! Most of the time it is in the 20-40% range.

Any way you skin the cat, you have to balance the nitrous fuel ratio, which incidentally is ranges from 5-6:1 nitrous to fuel (lb/hr) with most tune-ups set to 5.5:1.

Contraption has a pretty good handle on this stuff from the info he's shared, IMHO.

Mike

uh.
I dont really need a lesson on air fuel ratios.

If you think a slight bit of extra fuel is going to change total air/fuel much on a 400hp car, you are out of your mind. Maybe .2 change on the wideband.

Just because you dont feel comfortable on a jet size.....why do they sell it? Probably because it works and you havent tested to prove otherwise.

Also, huge power gains on small shots are only because the turbo overboosts because your wastegate setup sucks.
Thats not a real powergain.

[zin]

uh.
I dont really need a lesson on air fuel ratios.

If you think a slight bit of extra fuel is going to change total air/fuel much on a 400hp car, you are out of your mind. Maybe .2 change on the wideband.

Just because you dont feel comfortable on a jet size.....why do they sell it? Probably because it works and you havent tested to prove otherwise.

Also, huge power gains on small shots are only because the turbo overboosts because your wastegate setup sucks.
Thats not a real powergain.

I guess my 15 years working in the nitrous oxide field (mostly for NOS and Holley), doesn't qualify me to give advice... Tough crowd!

Mike Flynn

[8valves]

I guess my 15 years working in the nitrous oxide field (mostly for NOS and Holley), doesn't qualify me to give advice... Tough crowd!

Mike Flynn

Who is NOS or Holley? Don't they make carb-ama-taters?

[contraption22]

Ondonti,

There is more to balancing n20/fuel ratio than you are willing to accept, and thats fine. But please don't be a speed bump for the flow of knowlege between the ones that know, and the ones that want to learn. I certainly don't consider myself an expert on nitrous, but I have taken the knowlege from the ones that know. Mike "Zin" being one of them.


Perfect example.

Also, huge power gains on small shots are only because the turbo overboosts because your wastegate setup sucks.
Thats not a real powergain.

Wrong. In my testing. With 30hp jetting, went from 11.49 to 11.19, and trap went from 119 to 122mph. No boost control adjustments, same peak boost. No spike, no overboost, no creep. Back to back runs.

[Ondonti]

I guess my 15 years working in the nitrous oxide field (mostly for NOS and Holley), doesn't qualify me to give advice... Tough crowd!

Mike Flynn

Yeah, I guess maybe you could reply to the fact that having the jetting slightly wrong on a 400hp car magically changes the air/fuel ratio more then 0.2-3 or so.

You want to tell me that getting 30hp worth of fuel on 20hp worth of nitrous.

Then tack on 380hp worth of non nitrous HP that has the proper air fuel ratio....

So you end up getting 400hp worth of air but 410hp worth of fuel.

So you have changed the air fuel ratio 2.5%
Which on a 12:1 air fuel ratio would result in air fuel ratio being 11.7.
Considering the fact that you are spraying nitrous and spooling the turbo faster, its likely going to be unnoticed. Plus, overall, its probably safer!

Turbo guys often jet more fuel then n/a guys because of the whole boost control problem etc.

[Ondonti]

Ondonti,

There is more to balancing n20/fuel ratio than you are willing to accept, and thats fine. But please don't be a speed bump for the flow of knowlege between the ones that know, and the ones that want to learn. I certainly don't consider myself an expert on nitrous, but I have taken the knowlege from the ones that know. Mike "Zin" being one of them.


Perfect example.


Wrong. In my testing. With 30hp jetting, went from 11.49 to 11.19, and trap went from 119 to 122mph. No boost control adjustments, same peak boost. No spike, no overboost, no creep. Back to back runs.

More then I am willing to accept?

I did the math! Try it yourself!

Your 1/4 performance shows about a 20 whp gain on the trap speeds. Try the math! Rather then guessing
I consider that a Fail in your attempt to prove me wrong.

20whp from a 30 shot is pretty normal. usually 2/3 whp from the advertised numbers (depending on the brand...some are higher).

I just did the math again! Please explain this one with "oh well but my experience tells me that the math doesn't matter cause I/someone know everything." I suggest thinking critically instead of assuming things.