Since my car is a hotair car and im always fighting heat, i was wondering, how much alky is to much? Right now im at around 25% alky to fuel. i was thinking about cutting it back some after doing some reading on the board. When i go to the track i run C16 and alky. i use the alky for cooling only since i run good gas. however i also run pump gas and alky on the street. i was thinking of cutting the alky back some at the track and then even more on the street. was thinking maybe 15-18% on the track and about 10% on the street. anyways how much is to much or is there a thing? O also im running dual M15 nozzles with a turn on point around 3psi.
How Much Alky Is To Much?
- Thread starter Boost231
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I can only forward to you something I read in a car book awhile back. I tried to find it again, but I have too many tuning books and I couldn't find it. This is not the first time I've brought this statement up. I did try to warn people about this when alky injection was first becoming popular.
It was a short paragraph in a section that pertained to water/alcohol injection. It wasn't very descriptive and left more questions than it answered.
It went something like this:
Injecting large amounts of methanol as a coolant for a gasoline engine can cause the methanol to become unstable and can lead to preignition.
Sorry I can't offer anymore of an answer than that. I hate it when a source gives such a blanket statement like that.
Unfortunately, with methanol, there are no tuning signs that will warn you when you are getting to a point of preignition, at least in the way you guys are using the methanol. It will just happen. And, it happens very quick with devastating results.
I can only suggest that you keep your eyes open and watch the other fellas that are injecting a lot of methanol and pay attention to apparent common failures that these fellas are going through. From what I've seen so far, a pattern is starting to emerge.
Another thing about methanol. Any engine that is using methanol is going to be an animal all its own. Your car is going to have its own limit. Especially with you being a hot air car compared to an intercooled car.
It was a short paragraph in a section that pertained to water/alcohol injection. It wasn't very descriptive and left more questions than it answered.
It went something like this:
Injecting large amounts of methanol as a coolant for a gasoline engine can cause the methanol to become unstable and can lead to preignition.
Sorry I can't offer anymore of an answer than that. I hate it when a source gives such a blanket statement like that.
Unfortunately, with methanol, there are no tuning signs that will warn you when you are getting to a point of preignition, at least in the way you guys are using the methanol. It will just happen. And, it happens very quick with devastating results.
I can only suggest that you keep your eyes open and watch the other fellas that are injecting a lot of methanol and pay attention to apparent common failures that these fellas are going through. From what I've seen so far, a pattern is starting to emerge.
Another thing about methanol. Any engine that is using methanol is going to be an animal all its own. Your car is going to have its own limit. Especially with you being a hot air car compared to an intercooled car.
When i've tuned and had too much what I found was the motor choked and nosed down.
One thing on a hotair I wonder if its possible to fab a pipe to give some distance from the turbo to the IC. spacing out the nozzles may give better temperature control. Better said, spacing will give better temp control.
While I understand the motor can pre-ignite the methanol.. I have never had it happen.
I had a customer with a Nissan Skyline motor running 35 PSI boost.. and when it would hit the rev limiter at 9k.. dah dah dah... backfire.. blew the intake. Same thing can happen with 2 steps. You dont want alky spraying while the 2 step is on. if they dont hit the limiters, the boost is nt the problem.
One thing on a hotair I wonder if its possible to fab a pipe to give some distance from the turbo to the IC. spacing out the nozzles may give better temperature control. Better said, spacing will give better temp control.
While I understand the motor can pre-ignite the methanol.. I have never had it happen.
I had a customer with a Nissan Skyline motor running 35 PSI boost.. and when it would hit the rev limiter at 9k.. dah dah dah... backfire.. blew the intake. Same thing can happen with 2 steps. You dont want alky spraying while the 2 step is on. if they dont hit the limiters, the boost is nt the problem.
Another interesting tid bit of tuning information with methanol. This pertains more to the big boys running boosted pure methanol, but the chemistry is still interesting and could pertain to you fuel mixers in some fashion. Good information to know anyway.
Running an overly rich a/f mixture can cause preignition. You might be asking yourself, how is this possible?
An overly rich mixture of methanol can cause an overcooling situation that condenses some of the fuel out of the mixture causing a lean burn condition. Lean enough to cause unexplainable preignition.
Running an overly rich a/f mixture can cause preignition. You might be asking yourself, how is this possible?
An overly rich mixture of methanol can cause an overcooling situation that condenses some of the fuel out of the mixture causing a lean burn condition. Lean enough to cause unexplainable preignition.
Can't tell you at what point but I can tell you for a fact that Alky will Preignite! I used to work on a sprint car team and we had a bad engine explosion one night! We made the track paper 
Anyway the cause was a soggy rich condition to help get the car off the corner that night and the load and tune made a young drive wet his pants! It wasn't a hydro lock but preignition. I also read and heard Gas will do the same thing? I think it was like over 20-25% rich will in some cases cause preignition.
Jerry
Anyway the cause was a soggy rich condition to help get the car off the corner that night and the load and tune made a young drive wet his pants! It wasn't a hydro lock but preignition. I also read and heard Gas will do the same thing? I think it was like over 20-25% rich will in some cases cause preignition.Jerry
Very interesting. Thanks for sharing that.Can't tell you at what point but I can tell you for a fact that Alky will Preignite! I used to work on a sprint car team and we had a bad engine explosion one night! We made the track paper
Jerry
2QUICK2B6
Black Car Fever
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How much will the dual nozzle M15 nozzle system flow ?
That's 20-25% rich on a pure alcohol application. You can't really compare that with a mixed fuel situation.
darkred87T
Active Member
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The only time it seems to matter on my car is when I push the test button and it acts like it's flooding. Otherwise I know for a fact it lowers my WB AF ratio.
I just wonder if I should trim back fuel and compensate with alky at the track?
I just wonder if I should trim back fuel and compensate with alky at the track?
I wasn't planning on it, but the car is back together and the new converter setup is dying to be tested. Is there a WCN thread I can read up on for details?
Only if you have knock, then you raise alky amount and trim back fuel.
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I guess it depends on how much your car blows on the breathalyzer
Good one. :biggrin:
So true.
I had thought about running a dual nozzle set up but the more I though about it, I came to the conclusion that less is best. Use just enough to do the job. I can run 30lbs of boost with 25deg timing with a single m15 nozzle and 93oct. Alky knob on 7.
Plus you don't have to fill you bottle at every other stop light.
Every person I have heard that did testing on this subject said the more alky you run through the motor and trim out the gasoline will result in more power...I hear what you are saying about being to rich and causing preignition, but on a properly tuned car it won't be to rich just more alky to gasoline ratio.
