Relay to retard timing for nitrous??

[GPGTP]

For extra fuel with nos when iat resistor is used, set inj flow rate vs iat. I used .86 at 50C> [ used a resistor that read 60 C in the scanner]
This is for a dry setup

ah I see. With a wet kit I would just bake the fueling error introduced by iat into the fuel jet...using a window it's not a problem. Not a fan of dry kits, nor have I set one up so I can't comment on that.

[backchannel]

ah I see. With a wet kit I would just bake the fueling error introduced by iat into the fuel jet...using a window it's not a problem. Not a fan of dry kits, nor have I set one up so I can't comment on that.

I posted before realizing the op was using wet system.

[mtocrs1]

I have been thinkning about using this on my G8. I have the Nitrous kit just scared to use it until I understand how to tune correctly. The wifey will not be happy if I damage my car.
Just to be clear. This should not effect fueling on a MAF only tune but will affect an SD+MAF tune or SD only?
I am still learning so....
How is it effected in the VE tune? What map references the IAT for fueling.

[MikeOD]

If you're nervous about setting this up in the tune, make sure you keep the solenoids unhooked when you first try it. First just hook up the relay to the IAT and watch your timing as you turn it on and off...you'll see the spark cut immediately. After that, play things conservative with the nitrous and fuel jets until you know where you're playing as you're adding more power.

[SilverBullet6.0]

So what exactly needs to be done to the fueling for the iat range specified by the resistor? Or does the tune not adjust fueling based of iat?

[Ben Charles]

With nitrous your IAT's should dramatically lower, just set up the tune to pull timing if it gets hot or add fuel.

SD references IAT, in which it would add fuel b/c of the cooler IAT's

MAF IAT is not taken into the calculation.

[GPGTP]

it affects a/f when in speed density, but only when the relay is active, the relay is only active if your spraying....make up the error with your fuel jet.

If your dynamic airflow setting is stock then it's maf only above 4K anyway.

[LSxpwrdZ]

If we had access to all of the E85 tables we could use that for nitrous fueling and timing... EFILive uses it that way.

[IDRIVEAG8GT]

Very cool tech info. I wish we had subdivisions of the forums subjects for like, N/A, FI, and Nitrous. That way we could sticky pertaining info in each category.

[GPGTP]

If we had access to all of the E85 tables we could use that for nitrous fueling and timing... EFILive uses it that way.

not a bad idea. I assume you trick the pcm using the alcohol sensor?

[DSteck]

not a bad idea. I assume you trick the pcm using the alcohol sensor?

Yes, but you need to be able to generate a reliable frequency from 50 to 150Hz with a microcontroller.

HP Tuners doesn't have all of the parameters yet to enable Flex Fuel, though, so we can't do much right now with it.

[Justinjor]

I run mine through the ECT. Resistor set to 237*. Best part about it is the visual cue via the coolant temp gauge that tells me the car is for sure pulling the timing.

[V locity]

I run mine through the ECT. Resistor set to 237*. Best part about it is the visual cue via the coolant temp gauge that tells me the car is for sure pulling the timing.

Very nice!

[GPGTP]

Yes, but you need to be able to generate a reliable frequency from 50 to 150Hz with a microcontroller.

HP Tuners doesn't have all of the parameters yet to enable Flex Fuel, though, so we can't do much right now with it.

excellent; however, I will most likely never use this as I like using E85 for boost way more.

[bikewiz]

Yes, but you need to be able to generate a reliable frequency from 50 to 150Hz with a microcontroller.

HP Tuners doesn't have all of the parameters yet to enable Flex Fuel, though, so we can't do much right now with it.

Any update to this? I've got plenty of injector on my setup and was considering running a dry system and having the computer add fuel if there was a workaround to do so in an E38 computer.

[tmizer]

Same here, I had been running a 150 wet shot, but since I just installed a dual 267 pump Fore hat and 95 lb injectors, figured it be simpler and alot safer. Will give the IAT resistor mod a try.

[mbray01]

I would add 1 note, on the relays I installed I wired them to bypass through relay when nos is off, and to stack a resistor when nos is activated. I am in south louisiana and iats at the track can be 120 already, so by stacking I know I am not just pulling 8* from a stock map, but pulling 8* from what is already pulled. I have seen the setup described and was only pulling 1-2* over what had already been pulled, and motor was pinging away. Not very good. just my .02

[540gts]

I would add 1 note, on the relays I installed I wired them to bypass through relay when nos is off, and to stack a resistor when nos is activated. I am in south louisiana and iats at the track can be 120 already, so by stacking I know I am not just pulling 8* from a stock map, but pulling 8* from what is already pulled. I have seen the setup described and was only pulling 1-2* over what had already been pulled, and motor was pinging away. Not very good. just my .02

This is going to save me a lot of money and work. Could you elaborate on the stacked relays? Ant info would help.

[mbray01]

not stacked relays, but stacking a resistor on top of iat sensor using a 5 pin relay, in closed position it sees the iat only, in open or armed position it sees the iat plus the resistor. it requires learning what the iat resistance vs temp is and getting a resistor that would add "x" amount of degrees to achieve the amount of timing you want to retard. Of course you will have to play with the iat timing table as well if you are spraying a lot of nitrous.

[smcstevesmc]

Why not use a potentiometer (variable resistor) to be able to get at your exact ECT on the table ?