Does anyone run alcohol with an aftermarket ECM? How do you tune it? With the stock ECM you are adding alcohol along with fuel, with a wide band O2, more (fuel/alcohol?) would cause the ECM to pull fuel due to a rich A/F ratio. I would like to here from someone that has done it.
Alcohol tuning with FAST ECM?
- Thread starter Philv6
- Start date
No difference when you really think about it. AI is like an additional injector, so to compensate, you drop the PE in your fuel tables to offset the additional fuel.
On a stock ecm car, most drop fuel pressure 1-3 lbs and let the alky make up the difference.
Your hardest part in dialing in a "typical" system is that when it fires at a predetermined boost, it skews the AFR cuasing the AF to drop. Compensating for this condition is whats tricky. One of my first controllers sold was to a guy using DFI and a WB. Trim the box, and keep flat 11.5:1 AFR throughout the entire boost curve.
If the car is rich and the FAST is pulling fuel to compensate for a rich condition, then whats the issue? Talk about having an easier time
Since the goal is drop injector pw, replacing it with alky.
Your thinking adding additional fuel without doing anything.. even at this level it curbs detonation.
Makes some sense.
On a stock ecm car, most drop fuel pressure 1-3 lbs and let the alky make up the difference.
Your hardest part in dialing in a "typical" system is that when it fires at a predetermined boost, it skews the AFR cuasing the AF to drop. Compensating for this condition is whats tricky. One of my first controllers sold was to a guy using DFI and a WB. Trim the box, and keep flat 11.5:1 AFR throughout the entire boost curve.
If the car is rich and the FAST is pulling fuel to compensate for a rich condition, then whats the issue? Talk about having an easier time
Since the goal is drop injector pw, replacing it with alky.Your thinking adding additional fuel without doing anything.. even at this level it curbs detonation.
Makes some sense.
I have never seen anything that tells me my 3 wire heated o2 on a stock ECM is affected by alcohol. In this case Methanol.
You are supposed to try to run as much alcohol and the least gasoline as you can. But you will find you can only run so much alcohol to have it work right. In my case I found it worked out to about 1 part Methanol to 16 parts gasoline. Thats about a 6% mix. Now you have to realize that alcohol only has about half the BTU's or energy that gasoline has, so it really is only about 3% more fuel by volume.
I could be wrong but I don't think that will affect your o2 or AFR enough to matter. With more boost that little extra fuel won't hurt.
A long time ago when I had 36# bluetops and running 11.6 on race gas I turned the alky on to cover low o2's. They were 710's, and with the alky on went up to 730's without changing anything else.
However I don't know what it would do to a wideband o2. But I don't think it would do much.
You are supposed to try to run as much alcohol and the least gasoline as you can. But you will find you can only run so much alcohol to have it work right. In my case I found it worked out to about 1 part Methanol to 16 parts gasoline. Thats about a 6% mix. Now you have to realize that alcohol only has about half the BTU's or energy that gasoline has, so it really is only about 3% more fuel by volume.
I could be wrong but I don't think that will affect your o2 or AFR enough to matter. With more boost that little extra fuel won't hurt.
A long time ago when I had 36# bluetops and running 11.6 on race gas I turned the alky on to cover low o2's. They were 710's, and with the alky on went up to 730's without changing anything else.
However I don't know what it would do to a wideband o2. But I don't think it would do much.
Ok, so the goal for me would be to replace the 100% gasoline with a mixture target of 94/6 injected alcohol or methanol. Dennis you stated that it did in fact change your o2 numbers which means that it did show up as fuel across the sensor. But what you were shooting for was an actual percentage mix that worked best. So, with the fact that alcohol/methanol has a different BTU factor should the A/F target be changed to compensate? Example if the target was 11.5 for gasoline only would the new target be 11.3 due to the lower BTU energy? Is there a formula that gives target A/F ratios for different fuels?
Is 6% the max that could be injected before performance drops off? How much more pumping ability do the available kits have? Is 6% close to the pumps max, @ how much of the pump is used at that point?
Is it possible that the 6% was the correct ratio with the gasoline already being injected and that a higher ratio might work better if the gasoline could be trimed back?
You guys are making it very difficult to not move into the alcohol/methanol injection game.
Is 6% the max that could be injected before performance drops off? How much more pumping ability do the available kits have? Is 6% close to the pumps max, @ how much of the pump is used at that point?
Is it possible that the 6% was the correct ratio with the gasoline already being injected and that a higher ratio might work better if the gasoline could be trimed back?
You guys are making it very difficult to not move into the alcohol/methanol injection game.
Some serious investigation will show you how inaccurate the stock O2 sensors really are.
They're effected by mixture, backpressure, and EGT. You never really know where you are.
Stoich is stoich as far as an O2 sensor goes. The AFR will change, but a given WB output shows where you are in Lamda AFR wise.
The only thing, a stock O2 can do RELIABLY and ACCURATELY is tell you your richer or leaner then Stoich. These wifes' tales about it doing otherwise is what's lead in large part to so many blown headgaskets.
No.. you are over engineering something that is simple.
See if you pump too much alcohol into the motor, you get a drop in EGT's and the motor becomes lazy.. but doesnt KR.
Your wanting to know exactly how much "YOUR" motor will consume and be happy with. To which is impossible for anyone on the planet to predict. We can give you rule of thumb suggestions, but until you have a system setup in the car.. and are spraying..
If your wanting to know why, its simple. You run aftermarket turbo, ecm, cam, heads, exhuast,.. how can anyone know what are the charge air temps coming into your motor on a 70 degree day. When temps outside go to 100 degrees or 40 degrees.. things in the tune change. If the motor is heat soaked from sitting in traffic, or cool after being pulled of the trailer.. these things alter the requirements. If you make conditions whereas the motor can detonate more..obviously the requirments change and additional alky is needed. When conditions are optimal, then less is needed. Hence why I preach so much the in-car control.
See 94/6 may work great for 2 Slow's car. But maybe yours can see 92/8 or 90/10.. or 96/4.. See it requires methodical tuning to figure how much of each. Your only problem can come from spraying too little. Its extremely forgiving in dialing in if you have too much.
And if your car on alky runs fastest at 11.2 AFR, or 11.5 AFR.. the only place I know to answer that question is the track. Typically based on O2's and EGT's I see mid 1700's with no KR. And you may find the motor at 12.0 AFR will make the most power being sprayed.
Its not a fuel injector we're talking about. Its a mist nozzle shooting the air going into the motor. Its so barbaric.. its plain wonderful.
After doing many installs, and tuning.. its a walk in the park. I've done three installs in the last 7 days, on heavily modded cars.. its no issue. Believe it works.. hands down.
The pump/nozzle should be capable of delivering 45 ounces per minute. The pumps we use can deliver 1.8 GPM. So the pump isnt the issue. Additional nozzles can be added to increase the output accordingly. But at 45 ounces per minute, thats 7.5 ounces per 10 seconds. Which is usually enough to support any 10-11 second car.
HTH..
So if my thinking is correct, because my ECM will pull fuel to compensate for the injected alcohol I will need to use test and tune or buy an EGT sensor to maintain the correct exhaust temperatures. (Yes I know I will still need to tune) Then tune to create the correct exhaust temperature even if it means a really rich A/F ratio target. More alcohol, less gas same EGT temperature. Even if I run out of alcohol the ECM will throw a ton of fuel at it to maintain the heavy alcohol - rich A/F ratio. I think I got it. My installation would simple need me to add an EGT sensor to the items needed list. (Now I have to start research EGT gages.)
Razor, I think you took my comment wrong.
" You guys are making it difficult to not move into the alcohol/methanol injection game."
It was meant to say thanks for the support. With all the advice moving to alcohol is much easier than ever before.
Thanks
Razor, I think you took my comment wrong.
" You guys are making it difficult to not move into the alcohol/methanol injection game."
It was meant to say thanks for the support. With all the advice moving to alcohol is much easier than ever before.
Thanks
Well I need to answer both Bruce and Philv6.
First Bruce,
I don't understand. First you say the stock O2 is inaccurate, then you say the only thing it can do reliably and accurately is rich-lean. I hate to burst your bubble, but that's all it does is rich-lean. It's a one wire O2. Only one function. And I don't know how you think it is affected by backpressure or EGT. If by mixture you mean different fuel, then yes if you run C-16 it has lead in it that kills the stock O2. If you have a stock O2 it means you have a stock ECM. The chip sets all other functions. Lots of people that have a good chip and O2 run very well for a long time. No question that a WB, EGT, and something like FAST will let you tune better.
Philv6,
I hope you undrstand that I was only saying that 6% worked for me. I in no way would say it was right for everybody. I think it is a good starting point tho. I use a stock ECM and street chip. It's not an "alky chip". The point is that adding Methanol did not affect the tune of the chip, so I don't think you have to make any big or even small adjustments to start with to use alcohol. As Razor or any alky vendor will tell you start easy at say 19 lb of boost on a run. Check for KR, then go to 20 lb and 21lb and so on till you see some KR or lean or whatever and adjust till you find the max boost and proper tune.
I still get the sense that not just you but a lot of people are still a bit afraid of alcohol. Reminds me of 10 or 12 years ago when nitrous was the same way. Now kits are so well tuned that you just buy the right one and put it on. They know just the right amount of everything for about any motor these days. Well Razor and other good vendors have got it down pretty good now also. My problem when I started was I didn't know how much alcohol should be injected on a run or how much my setup was putting out. I had to go at it blind. Now with these kits they know just how much a certain size nozzle will deliver.
If it helps I run High 10's and I said 1 part alky to 16 parts gasoline. Well I know I use about half a gallon of gas on a run and half a cup of Methanol ( thats 8 oz.) so Razor is right on the money at 7.5 oz. for a 10-11 sec. car. And think about this. Whether it is a 12 sec. or 10 sec. car you will use about the same 8 oz. or so because you turn down the rate on a 12 sec. car but have the alcohol on 2 sec. longer than the 10 sec. car so the 10 sec. car gets more per second but about the same total. I could go on, but this is enough.
First Bruce,
I don't understand. First you say the stock O2 is inaccurate, then you say the only thing it can do reliably and accurately is rich-lean. I hate to burst your bubble, but that's all it does is rich-lean. It's a one wire O2. Only one function. And I don't know how you think it is affected by backpressure or EGT. If by mixture you mean different fuel, then yes if you run C-16 it has lead in it that kills the stock O2. If you have a stock O2 it means you have a stock ECM. The chip sets all other functions. Lots of people that have a good chip and O2 run very well for a long time. No question that a WB, EGT, and something like FAST will let you tune better.
Philv6,
I hope you undrstand that I was only saying that 6% worked for me. I in no way would say it was right for everybody. I think it is a good starting point tho. I use a stock ECM and street chip. It's not an "alky chip". The point is that adding Methanol did not affect the tune of the chip, so I don't think you have to make any big or even small adjustments to start with to use alcohol. As Razor or any alky vendor will tell you start easy at say 19 lb of boost on a run. Check for KR, then go to 20 lb and 21lb and so on till you see some KR or lean or whatever and adjust till you find the max boost and proper tune.
I still get the sense that not just you but a lot of people are still a bit afraid of alcohol. Reminds me of 10 or 12 years ago when nitrous was the same way. Now kits are so well tuned that you just buy the right one and put it on. They know just the right amount of everything for about any motor these days. Well Razor and other good vendors have got it down pretty good now also. My problem when I started was I didn't know how much alcohol should be injected on a run or how much my setup was putting out. I had to go at it blind. Now with these kits they know just how much a certain size nozzle will deliver.
If it helps I run High 10's and I said 1 part alky to 16 parts gasoline. Well I know I use about half a gallon of gas on a run and half a cup of Methanol ( thats 8 oz.) so Razor is right on the money at 7.5 oz. for a 10-11 sec. car. And think about this. Whether it is a 12 sec. or 10 sec. car you will use about the same 8 oz. or so because you turn down the rate on a 12 sec. car but have the alcohol on 2 sec. longer than the 10 sec. car so the 10 sec. car gets more per second but about the same total. I could go on, but this is enough.