Nitrous wiring waaay more complicated than expected

Finally got around to finishing up the nitrous system this week. I had originally planned on going old school, with a master switch and either a momentary switch on the shifter or a blade switch mounted on the throttle pedal bracket to trigger at WOT. Eventually I decided to add a line lock for burnouts and a 2-step for staging the car. I started getting concerned that with a manual and all the other gadgets that the amount of driver input required might eventually lead to triggering the nitrous at the wrong time and smoking my new motor. As I studied up on n2o systems, I discovered a window switch made by NOS that essentially automates most of the controls. It allows me to set my staging Rev limiter to a certain rpm, nitrous on to some number above that, then turns off just below my shift light RPM so it's not flowing when I shift, then comes back on when RPMs drop back into the window (but only at WOT.) The downside is MUCH more complicated wiring. Additionally, I integrated several other circuits for safety-
1- there is an auxiliary fuel pump for the nitrous system, running off a relay from the master "arm" switch
2- there is a fuel pressure switch inline with the pump, which cuts power to the solenoids if fuel pressure drops
3- the fuel tank for the nitrous system is the window washer reservoir, and the low washer fluid float also cuts power to the solenoids if the 103 octane fuel runs low
4- The N2O bottle heater is wired through a pressure switch on the valve, so the heater automatically turns off if pressure exceeds 950psi at the valve
5- there is a remote bottle opener so I can initialize the system from the driver's seat. Bottle is hidden under the spare tire cover in the back.

I have been drawing up the circuit schematics as I go, so troubleshooting and maintenance will be easier in the future. Here are a few pics-

All the nitrous controls are carefully hidden in the sunglass tray and slide-out ashtray

Line lock is controlled by the button on the shifter, and 2-step rev limiter switch is next to it on the console-

Here is the dash with controls hidden, and the tank location in the back-

Please pardon all the tools and hardware in the floorboard. I should have put up construction zone signs

Soooo, here's the tech question y'all knew was coming eventually. I've figured out how to hook up everything so far but ONE wire. I need a "hot in run" circuit to tap into for all the switches on the master control tray. They are ONLY low current switches to the relays for their respective jobs,so even piggybacking off a 10a circuit is plenty. I can run a wire to wherever necessary under or inside the dash, but I don't want to poke holes in 900 wires with my circuit tester. Any suggestions? I am mounting a 6 circuit fuse block behind the glove box for all the power sides of the relays, wired from the hot post on the fuse box right in front of the passenger side firewall. It should get here tomorrow, so that and the one switched wire are all that remain to be done.

Most of the "hot in run/start" wires are red with a lack stripe. Check the wire to the EVAP canister, or the air injection solenoid.

Awesome, that's a good place to start! Thank you Fred!

You have the nitrous fuel, 103 octane gas, in the windshield washer plastic bottle?

The inside of the bottle is coated with fuel tank sealer

I am a risk aversive person in general, but any way I look at having gasoline in a light weight plastic jug, it just looks like a very dangerous thing to do, coated or not.

Well, considering that the gas tank in these cars is a lightweight plastic jug 2 inches from a hot exhaust pipe, and the fuel cell in my race car is also plastic, it didn't seem too out of place. Especially since it will only have maybe a half gallon in it at a time. There's a company that's been making a methanol injection kit for turbo cars using the washer reservoir for years and they haven't been sued out of existence, yet anyways...

Sleeperwagon wrote:

Well, considering that the gas tank in these cars is a lightweight plastic jug 2 inches from a hot exhaust pipe, and the fuel cell in my race car is also plastic, it didn't seem too out of place. Especially since it will only have maybe a half gallon in it at a time. There's a company that's been making a methanol injection kit for turbo cars using the washer reservoir for years and they haven't been sued out of existence, yet anyways...

I ran an alcohol injection setup on my twin turbo 340 for 30 years from the time you had to build your own in the 1980s.  I  use isopropyl, though, because of the issues of corrosion with methanol.

I didn't, and didn't know of any that did, run pure alcohol in the system.  You run a 50/50 mix with water most often.  The enrichment system came from carb modifications early on and programmable EFI when if became available.

Unless things have changed it all still done that way with the methanol.

I just picked one brand at random and this is on the site in big bold text.

[size=16]

Quote :

THIS IS A RACE ONLY PRODUCT MANUFACTURED AND SOLD FOR INSTALLATION ON VEHICLES DESIGNED TO BE USED SOLELY FOR COMPETITION PURPOSES. ONCE THIS PART IS INSTALLED, THE VEHICLE MAY NEVER BE USED, OR REGISTERED OR LICENSED FOR USE, ON A PUBLIC ROAD OR HIGHWAY. IF YOU INSTALL THIS PART ON YOUR VEHICLE AND USE THE VEHICLE ON A PUBLIC ROAD OR HIGHWAY, YOU WILL VIOLATE THE CLEAN AIR ACT AND MAY BE SUBJECT TO PERSONAL CIVIL OR CRIMINAL LIABILITY, INCLUDING FINES OF UP TO $4,819 PER DAY.

IT IS THE RESPONSIBILITY OF THE INSTALLER AND/OR USER OF THIS PRODUCT TO ENSURE THAT IT IS USED IN COMPLIANCE WITH ALL APPLICABLE LAWS AND REGULATIONS. IF THIS PRODUCT WAS PURCHASED IN ERROR, DO NOT INSTALL AND/OR USE IT. THE PURCHASER MUST ARRANGE TO RETURN THE PRODUCT FOR A FULL REFUND.

THIS POLICY ONLY APPLIES TO INSTALLERS AND/OR USERS WHO ARE LOCATED IN THE UNITED STATES; HOWEVER, CUSTOMERS WHO RESIDE IN OTHER COUNTRIES SHOULD ACT IN ACCORDANCE WITH THEIR LOCAL LAWS AND REGULATIONS.

WARNING:
Misuse or improper tuning of this product can destroy your engine! If you are not well versed in engine dynamics DO NOT attempt the installation. Refer the installation to an AEM-trained tuning shop or call 800-423-0046 for technical assistance.

NOTE: IT IS THE RESPONSIBILITY OF THE ENGINE TUNER TO ULTIMATELY CONFIRM IF THE CALIBRATION IS SAFE FOR ITS INTENDED USE. AEM holds no responsibility for any engine damage that results from the misuse or mistuning of this product!

Important Safety Notice Regarding Methanol

AEM Water/Methanol Injection Systems are chemically compatible with a mixture of water and methanol, which we strongly recommend does not exceed a concentration of more than 50% methanol. In addition to inherent dangers of using 100% methanol, doing so will damage the system's flow sensor and void the warranty on this component.

Methanol is a toxic and highly flammable chemical. 100% Methanol ignites easily and burns vigorously with an almost undetectable flame. Methanol can be absorbed through the skin and even small amounts can cause blindness or even death. Using this fluid at high pressures, without dilution, in an under-hood environment with nylon lines and push-to-connect fittings is very unsafe. The performance advantages of using greater than 50% methanol concentrations are small, if they exist at all. However, the safety issues are very real and far outweigh any perceived benefit of running high concentrations of methanol.
Buy online from an Authorized Dealer

booster wrote:

Sleeperwagon wrote:

Well, considering that the gas tank in these cars is a lightweight plastic jug 2 inches from a hot exhaust pipe, and the fuel cell in my race car is also plastic, it didn't seem too out of place. Especially since it will only have maybe a half gallon in it at a time. There's a company that's been making a methanol injection kit for turbo cars using the washer reservoir for years and they haven't been sued out of existence, yet anyways...

I ran an alcohol injection setup on my twin turbo 340 for 30 years from the time you had to build your own in the 1980s.  I  use isopropyl, though, because of the issues of corrosion with methanol.

I didn't, and didn't know of any that did, run pure alcohol in the system.  You run a 50/50 mix with water most often.  The enrichment system came from carb modifications early on and programmable EFI when if became available.

Unless things have changed it all still done that way with the methanol.

I just picked one brand at random and this is on the site in big bold text.

[size=16]

Quote :

THIS IS A RACE ONLY PRODUCT MANUFACTURED AND SOLD FOR INSTALLATION ON VEHICLES DESIGNED TO BE USED SOLELY FOR COMPETITION PURPOSES. ONCE THIS PART IS INSTALLED, THE VEHICLE MAY NEVER BE USED, OR REGISTERED OR LICENSED FOR USE, ON A PUBLIC ROAD OR HIGHWAY. IF YOU INSTALL THIS PART ON YOUR VEHICLE AND USE THE VEHICLE ON A PUBLIC ROAD OR HIGHWAY, YOU WILL VIOLATE THE CLEAN AIR ACT AND MAY BE SUBJECT TO PERSONAL CIVIL OR CRIMINAL LIABILITY, INCLUDING FINES OF UP TO $4,819 PER DAY.

IT IS THE RESPONSIBILITY OF THE INSTALLER AND/OR USER OF THIS PRODUCT TO ENSURE THAT IT IS USED IN COMPLIANCE WITH ALL APPLICABLE LAWS AND REGULATIONS. IF THIS PRODUCT WAS PURCHASED IN ERROR, DO NOT INSTALL AND/OR USE IT. THE PURCHASER MUST ARRANGE TO RETURN THE PRODUCT FOR A FULL REFUND.

THIS POLICY ONLY APPLIES TO INSTALLERS AND/OR USERS WHO ARE LOCATED IN THE UNITED STATES; HOWEVER, CUSTOMERS WHO RESIDE IN OTHER COUNTRIES SHOULD ACT IN ACCORDANCE WITH THEIR LOCAL LAWS AND REGULATIONS.

WARNING:
Misuse or improper tuning of this product can destroy your engine! If you are not well versed in engine dynamics DO NOT attempt the installation. Refer the installation to an AEM-trained tuning shop or call 800-423-0046 for technical assistance.

NOTE: IT IS THE RESPONSIBILITY OF THE ENGINE TUNER TO ULTIMATELY CONFIRM IF THE CALIBRATION IS SAFE FOR ITS INTENDED USE. AEM holds no responsibility for any engine damage that results from the misuse or mistuning of this product!

Important Safety Notice Regarding Methanol

AEM Water/Methanol Injection Systems are chemically compatible with a mixture of water and methanol, which we strongly recommend does not exceed a concentration of more than 50% methanol. In addition to inherent dangers of using 100% methanol, doing so will damage the system's flow sensor and void the warranty on this component.

Methanol is a toxic and highly flammable chemical. 100% Methanol ignites easily and burns vigorously with an almost undetectable flame. Methanol can be absorbed through the skin and even small amounts can cause blindness or even death. Using this fluid at high pressures, without dilution, in an under-hood environment with nylon lines and push-to-connect fittings is very unsafe. The performance advantages of using greater than 50% methanol concentrations are small, if they exist at all. However, the safety issues are very real and far outweigh any perceived benefit of running high concentrations of methanol.
Buy online from an Authorized Dealer

Fair point on the methanol. As far as the lines, I drilled and tapped the bottom of the bottle 1/4NPT for a brass fitting, and ran automotive fuel line through a filter, pump, regulator, and solenoid hidden between the inner fender and firewall to the nozzles in the bottom of the manifold. The fittings for the washer circuits are blocked off and sealed at the tank, but left beside it to appear original.

May or may not be an issue for you ,
I had nitrous on a car long ago and thought a low pressure hobbs for fuel pressure would too be a good idea.
Your switch may be more sophisticated but the momentary dip in line pressure when the solenoid opened created nothing but grief.
What are your performace goals ?
Nabil (sp) still holds the B body stick car record.
Good luck with your project.

I don't know what you've got for fuel pressure, but a couple things I've been looking at:
1. PWM fuel pump control to avoid overpumping: https://www.vaporworx.com/shop/product/returnx-return-type-pwm-controller/
2. Fuel pump voltage booster (this kit includes the wiring you'd need, although it does not include the B-body specific connectors): https://www.jmschip.com/jms-products/fuelmax-category/

sherlock9c1 wrote:

I don't know what you've got for fuel pressure, but a couple things I've been looking at:
1. PWM fuel pump control to avoid overpumping: https://www.vaporworx.com/shop/product/returnx-return-type-pwm-controller/
2. Fuel pump voltage booster (this kit includes the wiring you'd need, although it does not include the B-body specific connectors): https://www.jmschip.com/jms-products/fuelmax-category/

Fuel supply for nitrous system is completely separate from the N/A fuel supply. The car has a high pressure in-tank pump supplying fuel to the OEM fuel rail and upgraded aftermarket injectors. The nitrous fuel supply is provided by an adjustable (6-10lb, currently running 7.5lb through the external regulator) electric pump mounted to the firewall. The pump is only powered when nitrous system is armed, and uses an internal regulator bypass so pressure drop is minimal when solenoid opens. The entire fuel system is less than 5ft long and only 6in from regulator to solenoid and 18in from solenoid to nozzles respectively. Entire fuel/solenoid/ control system is powered by 6-circuit fuse panel mounted behind the glove box wired to the distribution block just across the firewall from it.