Question for nitrous guys...
Thread Starter
Team Owner
Joined: Jul 2001
Posts: 182,997
Likes: 88
From: Lakeland, FL
Cruise-In IV-V-VI-VII-VIII Veteran
St. Jude Donor '03, '06, '17
Question for nitrous guys...
When going from naturally aspired to NOS, is there a rule of thumb on changes in carb jetting? I assume that I'll ned bigger jets when running spray..
What about timing? How many degrees do I have to retard the timing for a 150 shot?
What about timing? How many degrees do I have to retard the timing for a 150 shot?
Team Owner
Joined: Feb 1999
Posts: 34,453
Likes: 665
From: Republic of Texas
The general rule is for every 50hp retard 1 degree and one stage colder plugs. Though most people I know retard until after 100hp shots and 200hp shots and above you should have the block o-ringed.
Drifting
Joined: Sep 2003
Posts: 1,325
Likes: 6
From: FRANKLIN GA
No you don't need to change the jets in the carb. The kit you buy will have a chart of what jets to run in the spray bar plate for different HP levels. These are safe jetting combos. If you have a lot of black smoke (unburnt fuel) on your passes you can adjust them slightly or if you plan to run a progressive controller some have provisions to lean the fuel a bit without changing jets in the plate
The timing depends alot on the manufactor of the nitrous system. 2 degrees for every 50 is a common rule. some motors like more, some like less. You'll have to read your plugs to find out what yours wants.
Run plugs that are about 2 ranges cooler to start out.
Bigggest thing is read your plugs, be careful about adjusting the jetting or timing. Listen for detonation and read the plugs for signs of detonation. If you run a nitrous motor lean you will break it.
What kind of fuel sys are you running?
The timing depends alot on the manufactor of the nitrous system. 2 degrees for every 50 is a common rule. some motors like more, some like less. You'll have to read your plugs to find out what yours wants.
Run plugs that are about 2 ranges cooler to start out.
Bigggest thing is read your plugs, be careful about adjusting the jetting or timing. Listen for detonation and read the plugs for signs of detonation. If you run a nitrous motor lean you will break it.
What kind of fuel sys are you running?
Le Mans Master
Joined: Feb 2000
Posts: 7,032
Likes: 2
From: Newburgh NY
If not already planned, based on experience, might I also suggest:
WOT Switch on the gas pedal
Bottle Warmer
FPSS (FUel Pressure Safety Switch!!!)
RPM Window Switch (New MSG Digitals are only about $85
Each adds a little security from popping the top or detonating and burning a few valves.
WOT Switch on the gas pedal
Bottle Warmer
FPSS (FUel Pressure Safety Switch!!!)
RPM Window Switch (New MSG Digitals are only about $85
Each adds a little security from popping the top or detonating and burning a few valves.
Le Mans Master
Joined: Feb 2000
Posts: 7,032
Likes: 2
From: Newburgh NY
Originally Posted by AGVI
JOE! You sold the '78? WHY OH WHY?
www.vettetech.com
ps: The 34 is for sale also!
Thread Starter
Team Owner
Joined: Jul 2001
Posts: 182,997
Likes: 88
From: Lakeland, FL
Cruise-In IV-V-VI-VII-VIII Veteran
St. Jude Donor '03, '06, '17
Originally Posted by munday
You shouldn't need to change jet sizes if you are running a wet system, My Nitrous Express system uses a plate that adds the extra fuel and atomizes it. I think I am about 6 degrees of retarded :P
http://store.summitracing.com/defaul...=sniper+system
Don't think that it's a wet system...
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
2027 Corvette vs The World: Every C8 vs Its Closest Competitor
Joe Kucinski
10 Most Common Corvette Problems of the Last 20 Years!
Joe Kucinski
Thread Starter
Team Owner
Joined: Jul 2001
Posts: 182,997
Likes: 88
From: Lakeland, FL
Cruise-In IV-V-VI-VII-VIII Veteran
St. Jude Donor '03, '06, '17
Originally Posted by EDDIEJ82
No you don't need to change the jets in the carb. The kit you buy will have a chart of what jets to run in the spray bar plate for different HP levels. These are safe jetting combos. If you have a lot of black smoke (unburnt fuel) on your passes you can adjust them slightly or if you plan to run a progressive controller some have provisions to lean the fuel a bit without changing jets in the plate
The timing depends alot on the manufactor of the nitrous system. 2 degrees for every 50 is a common rule. some motors like more, some like less. You'll have to read your plugs to find out what yours wants.
Run plugs that are about 2 ranges cooler to start out.
Bigggest thing is read your plugs, be careful about adjusting the jetting or timing. Listen for detonation and read the plugs for signs of detonation. If you run a nitrous motor lean you will break it.
What kind of fuel sys are you running?
The timing depends alot on the manufactor of the nitrous system. 2 degrees for every 50 is a common rule. some motors like more, some like less. You'll have to read your plugs to find out what yours wants.
Run plugs that are about 2 ranges cooler to start out.
Bigggest thing is read your plugs, be careful about adjusting the jetting or timing. Listen for detonation and read the plugs for signs of detonation. If you run a nitrous motor lean you will break it.
What kind of fuel sys are you running?
Thread Starter
Team Owner
Joined: Jul 2001
Posts: 182,997
Likes: 88
From: Lakeland, FL
Cruise-In IV-V-VI-VII-VIII Veteran
St. Jude Donor '03, '06, '17
Originally Posted by Barry
Grandsport,
It says it is a wet system..... read the fine print!
It says it is a wet system..... read the fine print!
Drifting
Joined: Sep 2003
Posts: 1,325
Likes: 6
From: FRANKLIN GA
Yes it's a wet sys, dry sys's are for EFI cars
I don't mean the carb, I'm talking about pump, line sizes, regulators
If your running a dominator carb that sniper won't work they don't make them with a spread bore base, also it has small cheap plastic solenoids that wear out quickly. You have to go to the cheater series to get decent soleniods, my purge solenoid is the same one they use on the snipers and powershots if that tells you anything.
I don't mean the carb, I'm talking about pump, line sizes, regulators
If your running a dominator carb that sniper won't work they don't make them with a spread bore base, also it has small cheap plastic solenoids that wear out quickly. You have to go to the cheater series to get decent soleniods, my purge solenoid is the same one they use on the snipers and powershots if that tells you anything.
Thread Starter
Team Owner
Joined: Jul 2001
Posts: 182,997
Likes: 88
From: Lakeland, FL
Cruise-In IV-V-VI-VII-VIII Veteran
St. Jude Donor '03, '06, '17
Originally Posted by EDDIEJ82
Yes it's a wet sys, dry sys's are for EFI cars
I don't mean the carb, I'm talking about pump, line sizes, regulators
If your running a dominator carb that sniper won't work they don't make them with a spread bore base, also it has small cheap plastic solenoids that wear out quickly. You have to go to the cheater series to get decent soleniods, my purge solenoid is the same one they use on the snipers and powershots if that tells you anything.
I don't mean the carb, I'm talking about pump, line sizes, regulators
If your running a dominator carb that sniper won't work they don't make them with a spread bore base, also it has small cheap plastic solenoids that wear out quickly. You have to go to the cheater series to get decent soleniods, my purge solenoid is the same one they use on the snipers and powershots if that tells you anything.
Drifting
Joined: Sep 2003
Posts: 1,325
Likes: 6
From: FRANKLIN GA
At 100 shot you ought to be OK with that setup, but I seriously doubt it would feed that 406 and nitrous too at 150
Like 78vette said you'll also need:
Hobbs switch
Heater
Pressure gauge
Blow down tube
Purge kit
Window switch or Progressive controller
Like 78vette said you'll also need:
Hobbs switch
Heater
Pressure gauge
Blow down tube
Purge kit
Window switch or Progressive controller
Thread Starter
Team Owner
Joined: Jul 2001
Posts: 182,997
Likes: 88
From: Lakeland, FL
Cruise-In IV-V-VI-VII-VIII Veteran
St. Jude Donor '03, '06, '17
Originally Posted by EDDIEJ82
At 100 shot you ought to be OK with that setup, but I seriously doubt it would feed that 406 and nitrous too at 150
Like 78vette said you'll also need:
Hobbs switch
Heater
Pressure gauge
Blow down tube
Purge kit
Window switch or Progressive controller
Like 78vette said you'll also need:
Hobbs switch
Heater
Pressure gauge
Blow down tube
Purge kit
Window switch or Progressive controller
Anyway - I'm not ready to get a system yet.. I'll race the car on engine for about a month or 2 and then I'll add spray...
What are the options for fuels system upgrade? How could I upgrade fuel line size?? The bottle neck will be still the fuel sender unit.. Do you know of any unit with a larger fuel outlet??
Drifting
Joined: Sep 2003
Posts: 1,325
Likes: 6
From: FRANKLIN GA
The bottle heater is to keep the pressure up and regulated on the bottle. Without it you will never have consistent times at the track
You could go with a sump welded in the bottom of your stock tank, I've seen guys that just drill holes in the bottom of the tank and screw bulkhead connectors in it and cap off the original line. That way you don't have to change to a cell and the sender still works and run AN lines
You could go with a sump welded in the bottom of your stock tank, I've seen guys that just drill holes in the bottom of the tank and screw bulkhead connectors in it and cap off the original line. That way you don't have to change to a cell and the sender still works and run AN lines
Safety Car
Joined: Aug 2001
Posts: 3,892
Likes: 13
From: Pettis Performance 565 with two stages of Nitrous Supply nitrous 1.082, 4.61 at 155, 7.17 at 192
The sniper system is not a very good system. Oliver, give my buddies at nitrous supply.com a call and they will beat Summits prices. This company is run by Mike Thermos (Founder of NOS) 714 373 1986. Ask
for Mike Nelson or Mike Flynn, I know everyone there is named Mike.
For a 150 shot and good gas, a 2-6 degree retard is where you will want to be. You want the heat mark to be at the bend in the plug or less, if it is getting close to the threads you are getting a little hot.
As far as the carb goes; with a wet system and a small shot, there will be no need to do anything to it. As the shots get big you run less jet in the carb. This is due to the fact there is less signal from the motor due to the nitrous pressurizing the manifold. There is also work done to the boosters so they will pull fuel with less signal, for the same reason. This starts to apply at around the 250-350 hp level.
I would not feel comfortable running the motor and nitrous off one black pump. I would back it up with a seperate pump and line, a Holley 110 is fine and they come with one of the best regulators in the biz.
for Mike Nelson or Mike Flynn, I know everyone there is named Mike.
For a 150 shot and good gas, a 2-6 degree retard is where you will want to be. You want the heat mark to be at the bend in the plug or less, if it is getting close to the threads you are getting a little hot.
As far as the carb goes; with a wet system and a small shot, there will be no need to do anything to it. As the shots get big you run less jet in the carb. This is due to the fact there is less signal from the motor due to the nitrous pressurizing the manifold. There is also work done to the boosters so they will pull fuel with less signal, for the same reason. This starts to apply at around the 250-350 hp level.
I would not feel comfortable running the motor and nitrous off one black pump. I would back it up with a seperate pump and line, a Holley 110 is fine and they come with one of the best regulators in the biz.
Le Mans Master
Joined: Feb 2000
Posts: 7,032
Likes: 2
From: Newburgh NY
Bottle pressure should be no less than 800psi and best probably in the range of 950-1000psi for runs. The minute you take a run pressure will drop unless you immediately refill the bottole. If it's cooler out, as an example, even a full bottle can and will register well below 800psi until you warm it up and expand the gas and increase pressure. As mentioned, without it you will have no consistency.
Warmers come with a relay and thermostat to turn on below 900psi degrees and shut off around 1050psi to keep it in that sweet spot.
The blow-down tube, as mentioned, is also required at most tracks. If the bottle goes over 3000psi for some reason, a release cap blows and then the nitrous goes out the blow-down tube, out of the car, instead of in it. I use medical grade Nitrous so I'd rather it blow in the car!
Warmers come with a relay and thermostat to turn on below 900psi degrees and shut off around 1050psi to keep it in that sweet spot.
The blow-down tube, as mentioned, is also required at most tracks. If the bottle goes over 3000psi for some reason, a release cap blows and then the nitrous goes out the blow-down tube, out of the car, instead of in it. I use medical grade Nitrous so I'd rather it blow in the car!
Le Mans Master
Joined: Jul 2001
Posts: 9,622
Likes: 16
From: absecon nj
eddie not all efi cars,i run a wet system in mine,some are dry some are wet depends on the system for efi.All of my carb setups have always been wet too.
Also agree about a wot switch,not just a push button .
Also agree about a wot switch,not just a push button .
Drifting
Joined: Sep 2003
Posts: 1,325
Likes: 6
From: FRANKLIN GA
Hey Pat, wasn't it you that welded a sump in the bottom of your tank? I remember seeing one posted on here somewhere.
Thanks for the info on the EFI, didn't know that, but I've never ran nitrous on a efi car either
Thanks for the info on the EFI, didn't know that, but I've never ran nitrous on a efi car either