Nitrous and Methanol

[firebirdvert305]

Ive been researching this site and I havent really saw any information where anyone has used to two injections with sucess. Ive ordered my methanol kit and im looking to spray a small shot of spray as well on top of it, nothing big maybe a 50-60 shot to help on the top end. How well do these mixtures interact with each other? When injected at the sametime, could it be dangerous for EGT's? Any information pertaining to this topic would be great, even those who spray there engines, if you could chime in about your experiences id be great.

 

[scottsee]

Meth has a diffrent stoich value, you will need to caculate the actual A/F of the combustion chamber before adding nitrous. Click here. Once you've done that.. Best of luck to ya..

 

[delta448]

Nitrous will also act as a chemical intercooler when injected -same as meth, water/meth also acts like a high octane fuel, and nitrous will add lots of oxygen to the chemistry just to make the calculations near impossible for anyone with only a high school chemistry background (like me). Once you find the right AFR mix for the meth, you'll have to figure out the right quantity and ratios of the mixed meth/gasoline combination to add when you hit the nitrous.

I'm guessing you're wanting to increase meth concentration when nitrous is active(since it uses more O2 than gas during combustion), so if you find the perfect ratio of meth/nitrous, could you theoretically activate both the meth and the nitrous at the same time and not have to add much(if any) more gas?

I really hope you're better than me at chemistry.

 

[Caithness]

Meth has a diffrent stoich value, you will need to caculate the actual A/F of the combustion chamber before adding nitrous. Click here. Once you've done that.. Best of luck to ya..

See, I struggled with this question a while back. How to tune for the different stoich value of Methanol. Should I be running more like 9.5:1-10:1 with approx 30% methanol? How do I calculate exactly how much of my fuel is methanol? Etc etc.

Then somebody clued me in that the wideband O2 sensor is not an AFR sensor, it's a lambda sensor. It senses deviation from stoich, whatever stoich may be for the fuel you're running. It only shows the AFR readings because it's calibrated to show the correct AFR for standard gasoline for whatever lambda number the sensor is reading. So, when you start running methanol injection, whatever percentage of methanol you're injecting, whatever its stoich value might be and however far beneath that you are, none of this matters because the sensor is still reading the deviation from the effective stoich of whatever fuel mixture you're running. So that the "11:1" you're seeing on the gauge is probably 9:1, but means you're running proportionally as far under your real stoich as 11:1 is under 14.7:1. This confusion is why a lot of more advanced tuners tune by lambda instead of AFR, because AFRs are going to change from fuel to fuel but lambda values are largely going to stay the same excepting changes based on the cooling and anti-knock properties of various fuels which might allow a leaner mixture relative to stoich on certain fuels.

As for nitrous and methanol, all I've read in my limited research on the combo is that it's tricky to tune, and that the power gains from the nitrous will not be as high as usual because some of the charge cooling the nitrous usually accomplishes is already done by the methanol. So, your extra power is derived more from the 33% oxygen content compared to the standard 21% in air- not as impressive as the usual nitrous gains. A large amount of the power gain from nitrous is in the charge cooling, and you can still get that gain, but it won't be as big as it would be on a car without methanol. Running a wet nitrous system as people usually do on our cars, you're throwing more pump gas into the mix to fuel it, which is pushing you to a lower effective octane and throwing off your tuning. Maybe if you fed the nitrous jet methanol it would work better, but then your jet sizing would have to be increased to flow an equivalent amount of meth, and the usual shurflo pump setup to mister nozzles might have to be ditched for an independent meth fuel system. The pressure coming out of the shurflow would be too variable to get any consistency with a fuel solenoid opening and closing and changing the flow through the line in the typical pressure-unregulated meth injection setup. You might have to get a meth-safe fuel solenoid too. You see the complications that start to spring up and this for a nitrous setup that is going to produce less than the usual gains. Might as well just crank the boost and save the nitrous for the race-gas track runs.

Just my opinion on the matter.