AFR on dual nozzle methanol
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Instructor
Joined: Sep 2014
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AFR on dual nozzle methanol
Curious as to where you guys are running your afrs on dual nozzle kits, as well as your methanol controller gain settings? Trying to dial mine in with the controller still on 8 to eliminate any knock but it has been much trickier! Thanks in advance! nozzles are m10-m15, turns on at 2600rpms, intital voltage set to 12oclock. afr currently 12.8-13 before methanol activation and 11.8-12 after. I think i am still rich but just looking for advice.
Pro
Joined: Oct 2008
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From: Nashville, TN
Ah, that makes sense. You are running the most boost I have seen on here so will probably have different alky settings. Whats that like 950 rwhp?
I think your AFR looks good. I remember Doug saying a lot of meth from dual nozzles doesn't necessarily distribute well to all 8 cylinders so I would keep it on the rich side.
I think your AFR looks good. I remember Doug saying a lot of meth from dual nozzles doesn't necessarily distribute well to all 8 cylinders so I would keep it on the rich side.
Thread Starter
Instructor
Joined: Sep 2014
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Ah, that makes sense. You are running the most boost I have seen on here so will probably have different alky settings. Whats that like 950 rwhp?
I think your AFR looks good. I remember Doug saying a lot of meth from dual nozzles doesn't necessarily distribute well to all 8 cylinders so I would keep it on the rich side.
I think your AFR looks good. I remember Doug saying a lot of meth from dual nozzles doesn't necessarily distribute well to all 8 cylinders so I would keep it on the rich side.
Thank you. I am right around 800whp. Still on the stock cam, im sure I would be over 900 with a camshaft. I guess my question now is how rich is really too rich on these di motors? I would like to keep it as rich as possible for thermal control. my understanding is it can be even worse to have these motors too rich. I don't mind leaving a few hp on the table for reliability. Should I be richer before the methanol injection turns on?
Racer
Joined: Jul 2007
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From: Jax FL
Thank you. I am right around 800whp. Still on the stock cam, im sure I would be over 900 with a camshaft. I guess my question now is how rich is really too rich on these di motors? I would like to keep it as rich as possible for thermal control. my understanding is it can be even worse to have these motors too rich. I don't mind leaving a few hp on the table for reliability. Should I be richer before the methanol injection turns on?
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Instructor
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thanks. Up top is not where I am actually worried about too much. I am more concerned with when the methanol actually comes on (because there is alot of it) causing me to pull a lot of fuel to get it in line. I am also concerned about the 4k-5500 area as that is where there is max load/tq.
Racer
Joined: Jul 2007
Posts: 441
Likes: 156
From: Jax FL
thanks. Up top is not where I am actually worried about too much. I am more concerned with when the methanol actually comes on (because there is alot of it) causing me to pull a lot of fuel to get it in line. I am also concerned about the 4k-5500 area as that is where there is max load/tq.
You may want to actually dial the meth down a bit as too much is not good. With the gain ****(blue) turned to minimum, you should see some knock but not a whole lot. Typically less than 2 degrees at WOT. Increasing the gain **** should make the motor go to zero knock. If your setting is at minimum and you don’t see any knock, you may have too much alcohol being sprayed. The adjustment that affects this is the **** inside the PAC controller labeled “INITIAL”. Turning this screw counterclockwise reduces the ramp and puts less alcohol/water into the motor. Small adjustments make big changes. Repeat the procedure until the motor just has enough alcohol to curb the detonation, but not too much.
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Thread Starter
Instructor
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My meth (single) comes on early (2100) and stays on till 6500. You say you have alot which concerns me, that youmay be putting too much into the system. This was taken right from the AlkyInjection Site. (see below)
You may want to actually dial the meth down a bit as too much is not good. With the gain ****(blue) turned to minimum, you should see some knock but not a whole lot. Typically less than 2 degrees at WOT. Increasing the gain **** should make the motor go to zero knock. If your setting is at minimum and you don’t see any knock, you may have too much alcohol being sprayed. The adjustment that affects this is the **** inside the PAC controller labeled “INITIAL”. Turning this screw counterclockwise reduces the ramp and puts less alcohol/water into the motor. Small adjustments make big changes. Repeat the procedure until the motor just has enough alcohol to curb the detonation, but not too much.
You may want to actually dial the meth down a bit as too much is not good. With the gain ****(blue) turned to minimum, you should see some knock but not a whole lot. Typically less than 2 degrees at WOT. Increasing the gain **** should make the motor go to zero knock. If your setting is at minimum and you don’t see any knock, you may have too much alcohol being sprayed. The adjustment that affects this is the **** inside the PAC controller labeled “INITIAL”. Turning this screw counterclockwise reduces the ramp and puts less alcohol/water into the motor. Small adjustments make big changes. Repeat the procedure until the motor just has enough alcohol to curb the detonation, but not too much.
Racer
Joined: Jul 2007
Posts: 441
Likes: 156
From: Jax FL
Then maybe you should have it come on earlier so the ramp rate starts sooner, so by the time you do the initial hit the system should in essence be at or close to the mark. I can see the pump getting lazy as it doesn't have to support as much off the top. I would at least give it a try and datalog it (or dyno too if you have one available) Also just because the pump seems lazy doesn't really mean it is. If I'm correct the pump maxes out at 150 psi which you would never see.
Racer
Joined: Jul 2007
Posts: 441
Likes: 156
From: Jax FL
Here are a few threads that Julio posted in about dual nozzles and settings. The 2nd thread in particular should be helpful, as the first.
https://www.corvetteforum.com/forums...-settings.html
https://www.corvetteforum.com/forums...-question.html
You can always email him he is pretty quick to answer.
https://www.corvetteforum.com/forums...382-julio.html
https://www.corvetteforum.com/forums...-settings.html
https://www.corvetteforum.com/forums...-question.html
You can always email him he is pretty quick to answer.
https://www.corvetteforum.com/forums...382-julio.html
Thread Starter
Instructor
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Then maybe you should have it come on earlier so the ramp rate starts sooner, so by the time you do the initial hit the system should in essence be at or close to the mark. I can see the pump getting lazy as it doesn't have to support as much off the top. I would at least give it a try and datalog it (or dyno too if you have one available) Also just because the pump seems lazy doesn't really mean it is. If I'm correct the pump maxes out at 150 psi which you would never see.
Racer
Joined: Jul 2007
Posts: 441
Likes: 156
From: Jax FL
I do datalog it, if anything I would start it later. I am right on the edge of it already being too early but i have tried it may different ways and it seems to be the easiest to tune right here at 2600 because of how my timing curve is structured. I see the max 150psi around 6k because that is where i peg my 2 bar map sensor on the system. I am really just looking for AFRs that others have had success with and methanol gain settings for users with a dual nozzle. I do appreciate your input!
Damon
