Race Gas or Meth????
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Originally Posted by Glex25
93+50/50 meth mix = C16
Don't know how you guys have yours setup.
My setup only sprays after 3psi to cool off the motor
and up the octane.
Don't know how you guys have yours setup.
My setup only sprays after 3psi to cool off the motor
and up the octane.
If 93+50/50 meth mix = C16........what do you get with 93+100% Meth
Jet Fuel
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Originally Posted by Glex25
Do you guys have it set for the meth to turn on at a certain PSI(or RPM)?
Running it all the time?
I have the Utec no control for external stuff like that so i use the meth controller as a stand alone.
Hence my whole reasoning to go with a standalone ems.
Running it all the time?
I have the Utec no control for external stuff like that so i use the meth controller as a stand alone.
Hence my whole reasoning to go with a standalone ems.
Originally Posted by athenG
I know some site has exaggerated this numbers but if Methanol only have an octane rating of 114 (some site has it 101) then how can this lead to 117 (c16 octane rating) if you are only spraying 50% meth so if you average it down then it should be lower since the big portion of your fuel is still 93 octane. It is probably close to high 90's rather than above 100 octane.. 

I'm not going to argue what the octane rating is.
I adjust my timing and fuel maps accordingly when spraying meth.
I'm just happy I was able to bring down my Injector duty cycle
with Meth so I don't have to spray so much fuel to cool the motor.
I know you have been running Meth kit longer than I have so
you probably research more than i have on it.
As a rule of thumb, 50/50 Water/Methanol injection will increase the octane rating of pump gas by 25% during injection. (Note that C16 Race gas is already 116 octane, W/M will slow flame more). So with a load based injection system, you only get the octane increase when needed.
Water is capable of cooling the combustion chamber more efficiently then gasoline. Water has a higher Latent Heat of Vaporization then gasoline. When water is injected in very small droplet sizes into the combustion chamber, it readily absorbs heat as the partials go from liquid to gas state. The water particles actually “pop” or create multiple micro explosions. These micro explosions help to slow the flame front, effectively increasing the octane rating. These micro explosions also help to “stir” the air fuel charge or create a swirl effect in the combustion chamber. This swirl effect results in a more complete combustion of the fuel, leading to lower NOx emissions. With a more complete combustion, engine knock is reduced. This is due to the lower amount of gases available after combustion that can spontaneously combust.
Water is capable of cooling the combustion chamber more efficiently then gasoline. Water has a higher Latent Heat of Vaporization then gasoline. When water is injected in very small droplet sizes into the combustion chamber, it readily absorbs heat as the partials go from liquid to gas state. The water particles actually “pop” or create multiple micro explosions. These micro explosions help to slow the flame front, effectively increasing the octane rating. These micro explosions also help to “stir” the air fuel charge or create a swirl effect in the combustion chamber. This swirl effect results in a more complete combustion of the fuel, leading to lower NOx emissions. With a more complete combustion, engine knock is reduced. This is due to the lower amount of gases available after combustion that can spontaneously combust.
Last edited by Glex25; Aug 5, 2008 at 08:56 AM.
Originally Posted by Audible Mayhem
the issue with meth is the liability if it isnt working correctly. from a shops point of view, i dont want to see anyone driving on the "meth" map when the meth isnt working correctly.
i love race gas, its in there EVERY time you put it in the tank...
i love race gas, its in there EVERY time you put it in the tank...
Last edited by rcdash; Aug 5, 2008 at 08:59 AM.
Originally Posted by XKR
+1000000
Plus my Meth Kit is controlled by the F-con.
Plus my Meth Kit is controlled by the F-con.
how does the F-con work w/ the meth kit? How does it activate the safety map if something fails?
Originally Posted by rcdash
JT, if you set up a submap for ignition timing advance and fuel compensation based only on air intake temperatures (rather than depending on the flow of methanol), would you be able to set up a fool proof methanol tune that does not depend on injection reliability?
i would figure the variations in air temp would cause a issue with doing this (unless you can set it to a value that represents a difference between ambient and intake temp)
Originally Posted by chris'smax
i would figure the variations in air temp would cause a issue with doing this (unless you can set it to a value that represents a difference between ambient and intake temp)
Relying on an external circuit for injection failure seems precarious.
Last edited by rcdash; Aug 5, 2008 at 09:07 AM.
Originally Posted by rcdash
JT, if you set up a submap for ignition timing advance and fuel compensation based only on air intake temperatures (rather than depending on the flow of methanol), would you be able to set up a fool proof methanol tune that does not depend on injection reliability? If that is possible, what performance are you leaving on the table for the added measure of safety? Even if you can realize 50% of the performance benefit, I'd say it's worth the trade off for a fool proof setup.
I know most if not all meth kits spray after the MAF and closer to the TB.
+1 on the EGT and AFR feedback being the best scenario for the submap trigger
Originally Posted by Glex25
Yeah just reading online and thats what I found.
I'm not going to argue what the octane rating is.
I adjust my timing and fuel maps accordingly when spraying meth.
I'm just happy I was able to bring down my Injector duty cycle
with Meth so I don't have to spray so much fuel to cool the motor.
I know you have been running Meth kit longer than I have so
you probably research more than i have on it.
http://www.legacygt.com/forums/showthread.php?t=84700
I'm not going to argue what the octane rating is.
I adjust my timing and fuel maps accordingly when spraying meth.
I'm just happy I was able to bring down my Injector duty cycle
with Meth so I don't have to spray so much fuel to cool the motor.
I know you have been running Meth kit longer than I have so
you probably research more than i have on it.
http://www.legacygt.com/forums/showthread.php?t=84700
Yes I have seen those site.. funny is that most website that advertise that are the meth kit company themselves..
Originally Posted by Glex25
Isn't it that most systems use the MAF for air intake temps?
I know most if not all meth kits spray after the MAF and closer to the TB.
+1 on the EGT and AFR feedback being the best scenario for the submap trigger
I know most if not all meth kits spray after the MAF and closer to the TB.
+1 on the EGT and AFR feedback being the best scenario for the submap trigger
Last edited by rcdash; Aug 5, 2008 at 10:09 AM.
Originally Posted by athenG
Yes I have seen those site.. funny is that most website that advertise that are the meth kit company themselves..
Do you buy pre-made mix or do you mix your own? curious how many timing advance did you push your motor and what is your target A/F? I only added 2-3 deg and lean out the A/F to around 11.5-11.6 since I want to stay on the safe side just in case if my meth kit fail ( I don't have a fancy EMS that can switch map..lol).
Only did a few dyno pulls since I installed it on Friday and have to clean up the installation.
I will do a few more pulls then test it on the road.
I made my own mix 5 gallon of Meth($45) and 5 Gallons of distilled water($5+)(55/45?).
No fancy EMS here just a EMS that works(Utec w/ map switch)
Last edited by Glex25; Aug 5, 2008 at 10:18 AM.
Even if you don't have a fancy EMS, if your METH kit provides a trigger if your injection fails, you could use it with a relay to cut your boost solenoid duty cycle to 0 and fall back to wastegate pressure. That along with an idiot light would probably be reasonable protection (as long as you were paying attention).
Last edited by rcdash; Aug 5, 2008 at 11:51 AM.
Originally Posted by Barzten1
I run about 1/3 race gas at all times for last 3 years. Its unleaded 101. Is this bad for your o2's
Interesting thread. I've been looking at options in the water/meth arena for use with a Haltech but am still undecided. I wouldn't be using it for a major power increase as much as cooler AIT's under high boost.
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Originally Posted by chris'smax
how does the F-con work w/ the meth kit? How does it activate the safety map if something fails?
Once I ran out of meth and I did not know....I had the boost set to 15psi's and it would not go over 11......it was very hot outside. Could not figure it out until I desided to check the meth tank......empty
Just do the meth Chris....you cant go wrong. You know me...if it does not work I will tell.
Originally Posted by taurran
Interesting thread. I've been looking at options in the water/meth arena for use with a Haltech but am still undecided. I wouldn't be using it for a major power increase as much as cooler AIT's under high boost.
Originally Posted by 05Z33
As long as its unleaded you should be fine. I've been putting 103 unleaded in my car without any problems.
Originally Posted by Barzten1
I run about 1/3 race gas at all times for last 3 years. Its unleaded 101. Is this bad for your o2's
... assuming you put 15 gal at a time, so that is 5 gal of 101 and 10 gal of 93 octane and total of 15 gal of mix (1/3 ratio). That is 33.3% Race Gas (101 octane) and the rest (66.6% 93octane). So [(33.3x101)+(66.6x93)]x100=95.57 or about 95.6 octane increase after the mix. Not sure how much you pay for your 101 but I'm guessing you are paying around $35 or even more for a 5 Gal of 101. With meth you only spray when on boost so you don't wast it when cruising around.
Correct me if my math is wrong but I don't have time to validate it since I have to leave work now..lol
Last edited by athenG; Aug 5, 2008 at 01:24 PM.
Guys, i know everyone on here is going to rep what they are running and they should, but if you are going to state a opinion please give some factual information to back it up. That way this thread can gain some educational value.
I am not calling anyone out, i just don't want this to turn into a typical "i did it so its the best" my350z thread.
I am not calling anyone out, i just don't want this to turn into a typical "i did it so its the best" my350z thread.
Originally Posted by chris'smax
Guys, i know everyone on here is going to rep what they are running and they should, but if you are going to state a opinion please give some factual information to back it up. That way this thread can gain some educational value.
I am not calling anyone out, i just don't want this to turn into a typical "i did it so its the best" my350z thread.
I am not calling anyone out, i just don't want this to turn into a typical "i did it so its the best" my350z thread.


