lt1 n20 help
01-19-2012, 08:23 PM
#1
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Location: benson nc
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lt1 n20 help
hey guys i have a 95 camaro z28 automatic it have 120k miles rebuild tranny and beefed it up some in last 5k miles has 2500 stall stock rear only moda are throttle body , cai , long tube headers , full slp lm1 exhaust, i have #32 injectors that i havnt instaled yett. im wanting to run a 100 shot but im new to nitrous so idk wether to go wet or dry and if a 100 **** is safe with it being my daily driver.
what all do i need to make it right so i dont blow haha another question is can pcms for less give a good nitrous tune or should i let Rpm motorsports do it with the being 10 min from home?
any help would be great thanks guys
what all do i need to make it right so i dont blow haha another question is can pcms for less give a good nitrous tune or should i let Rpm motorsports do it with the being 10 min from home?
any help would be great thanks guys
01-19-2012, 10:21 PM
#2
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Location: Hell was full so they sent me to NJ
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Re: lt1 n20 help
Generally, you don't tune the PCM for nitrous at all. You optimize the tune to run the engine without the nitrous. Then you add an external timing retard box to retard timing when you spray.
With a wet system, you leave the PCM alone, and use "jets" (restriction orifice) in the nitrous and fuel supply lines to control the A/F ratio when you spray.
With a dry system on the LT1 the system will incorporate a pressure regulator that bleeds down nitrous pressure of a small slipstream, and applies that pressure to the fuel pressure regulator to increase the fuel pressure to supply the extra fuel when you spray. Again, you tune the system with jets, although I found the tuning with the NOS 5176 dry system to be sort of hit or miss.
With either system, you only spray at 3,000rpm and above, and you only spray at WOT. Then it's a good idea to use an ignition box that cuts spark on the rev limiter, and set that slightly below the PCM rev limiter, which cuts fuel. You accomplish the lower and upper rev limits with a window switch, and use a WOT switch to allow the system to operate only when the throttle is wide open. There are both mechanical and electronic WOT switches. Consider a non-extended nose plug a step colder than stock.
I ran a 125-shot on the stock bottom end for about 5 years, but that was when the engine had less than 70K miles. Whether your engine will be happy with a 100-shot is hard to say - depends on the condition.
With a wet system, you leave the PCM alone, and use "jets" (restriction orifice) in the nitrous and fuel supply lines to control the A/F ratio when you spray.
With a dry system on the LT1 the system will incorporate a pressure regulator that bleeds down nitrous pressure of a small slipstream, and applies that pressure to the fuel pressure regulator to increase the fuel pressure to supply the extra fuel when you spray. Again, you tune the system with jets, although I found the tuning with the NOS 5176 dry system to be sort of hit or miss.
With either system, you only spray at 3,000rpm and above, and you only spray at WOT. Then it's a good idea to use an ignition box that cuts spark on the rev limiter, and set that slightly below the PCM rev limiter, which cuts fuel. You accomplish the lower and upper rev limits with a window switch, and use a WOT switch to allow the system to operate only when the throttle is wide open. There are both mechanical and electronic WOT switches. Consider a non-extended nose plug a step colder than stock.
I ran a 125-shot on the stock bottom end for about 5 years, but that was when the engine had less than 70K miles. Whether your engine will be happy with a 100-shot is hard to say - depends on the condition.
Last edited by Injuneer; 01-19-2012 at 10:23 PM.
01-21-2012, 01:44 PM
#3
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Join Date: Feb 2011
Location: benson nc
Posts: 190
Re: lt1 n20 help
Generally, you don't tune the PCM for nitrous at all. You optimize the tune to run the engine without the nitrous. Then you add an external timing retard box to retard timing when you spray.
With a wet system, you leave the PCM alone, and use "jets" (restriction orifice) in the nitrous and fuel supply lines to control the A/F ratio when you spray.
With a dry system on the LT1 the system will incorporate a pressure regulator that bleeds down nitrous pressure of a small slipstream, and applies that pressure to the fuel pressure regulator to increase the fuel pressure to supply the extra fuel when you spray. Again, you tune the system with jets, although I found the tuning with the NOS 5176 dry system to be sort of hit or miss.
With either system, you only spray at 3,000rpm and above, and you only spray at WOT. Then it's a good idea to use an ignition box that cuts spark on the rev limiter, and set that slightly below the PCM rev limiter, which cuts fuel. You accomplish the lower and upper rev limits with a window switch, and use a WOT switch to allow the system to operate only when the throttle is wide open. There are both mechanical and electronic WOT switches. Consider a non-extended nose plug a step colder than stock.
I ran a 125-shot on the stock bottom end for about 5 years, but that was when the engine had less than 70K miles. Whether your engine will be happy with a 100-shot is hard to say - depends on the condition.
With a wet system, you leave the PCM alone, and use "jets" (restriction orifice) in the nitrous and fuel supply lines to control the A/F ratio when you spray.
With a dry system on the LT1 the system will incorporate a pressure regulator that bleeds down nitrous pressure of a small slipstream, and applies that pressure to the fuel pressure regulator to increase the fuel pressure to supply the extra fuel when you spray. Again, you tune the system with jets, although I found the tuning with the NOS 5176 dry system to be sort of hit or miss.
With either system, you only spray at 3,000rpm and above, and you only spray at WOT. Then it's a good idea to use an ignition box that cuts spark on the rev limiter, and set that slightly below the PCM rev limiter, which cuts fuel. You accomplish the lower and upper rev limits with a window switch, and use a WOT switch to allow the system to operate only when the throttle is wide open. There are both mechanical and electronic WOT switches. Consider a non-extended nose plug a step colder than stock.
I ran a 125-shot on the stock bottom end for about 5 years, but that was when the engine had less than 70K miles. Whether your engine will be happy with a 100-shot is hard to say - depends on the condition.
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