Afr drop of 3points with dual nozzle meth, normal?
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Afr drop of 3points with dual nozzle meth, normal? Running dual 15s alky control. With the initial pump pressure very low and 10psi turn on and 20psi boost I go from 12.9 afr to 11.2.
Julio does not suggest such a low turn on. If i put it at the 12 o'clock position its in the low 10s.
I have no meth under 11psi and if I were to put it back down to 5psi turn on it would go 9s afr.
Car puts down 900whp, ive seen guys with less and the same nozzle.
Is this too much nozzle or is it normal to literally have to command like 13.5 afr to get 11.0afr with meth?
Julio does not suggest such a low turn on. If i put it at the 12 o'clock position its in the low 10s.
I have no meth under 11psi and if I were to put it back down to 5psi turn on it would go 9s afr.
Car puts down 900whp, ive seen guys with less and the same nozzle.
Is this too much nozzle or is it normal to literally have to command like 13.5 afr to get 11.0afr with meth?
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Julio knows his stuff and I'd listen to him. You want the meth to come on earlier than 10 psi for sure. I think you just have too much nozzle. I just went from a 15 and 10, to a 15 ad 5, and may even step down again. It was loading up at full throttle and getting too rich.
If you use it like a fuel, then tune as part of the fuel system. I'll always dial the VE table with the meth spraying. I never/ever touch the PE table. Alky controls kit is very consistant on delivery.
For 20 psi I'll ramp it at 6-8psi.
For 20 psi I'll ramp it at 6-8psi.
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What is the gain set @? Also what kind of power? Whats happening is the fuel is more than needed and you are going rich, are you getting spark knock? Also your a/f value will be diff when at wot on meth mix vs pump gas straight. I ran a similar setup with 1 m15 nozzle and pump gas. Is e85 readily available to you?
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Once you start putting that much supplemental fuel in it, regardless whether or not you just want it there for the cooling purposes...you have to pull fuel back in the tune. On aggressive big turbo setups I command stoich all the time. Meth takes care of all of the enrichment. Would the engine blow up if the meth quit working? Unfortunately, yes. But if you are working with a stock PCM, that's what you've got to do. Take extra care to filter your methanol, though. With a setup that is reliant on the methanol to make power and stay alive, you can't afford for debris to be getting in the tank and clogging up the nozzles.
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Slowhawk, that's exactly how I want to do it. The tuner yesterday changed some ve but made the pe and be command 12.8 afr to get to 11.2. I didn't like that at all. With no meth in the lower boost range its at 12.8afr, not cool.
At this point im going to go back to my non meth tune and use c16 to go to the track saturday. Ive been trying to learn how to tune on a 900whp as my first and wasted a lot of money on the dyno.
Il study up this winter and get back at this meth thing next year.
At this point im going to go back to my non meth tune and use c16 to go to the track saturday. Ive been trying to learn how to tune on a 900whp as my first and wasted a lot of money on the dyno.
Il study up this winter and get back at this meth thing next year.
Jake there are several safety features you can setup to prevent engine failure if your meth injection quits. I've setup several cars like this and have had meth pumps quit with out harming the engine at all. Just like slowhawk said you need to tune the meth as part of your ve. With as much meth as you're spraying even if it did quit I doubt you would hurt anything as it would go so lean once its tuned to equal your commanded afr.
Jake there are several safety features you can setup to prevent engine failure if your meth injection quits. I've setup several cars like this and have had meth pumps quit with out harming the engine at all. Just like slowhawk said you need to tune the meth as part of your ve. With as much meth as you're spraying even if it did quit I doubt you would hurt anything as it would go so lean once its tuned to equal your commanded afr.
I am aware of several 'methods' people use to try to prevent damage in the event of meth failure, but none that I would trust to react fast enough or work properly in the event of a failure.
Slowhawk, that's exactly how I want to do it. The tuner yesterday changed some ve but made the pe and be command 12.8 afr to get to 11.2. I didn't like that at all. With no meth in the lower boost range its at 12.8afr, not cool.
At this point im going to go back to my non meth tune and use c16 to go to the track saturday. Ive been trying to learn how to tune on a 900whp as my first and wasted a lot of money on the dyno.
Il study up this winter and get back at this meth thing next year.
At this point im going to go back to my non meth tune and use c16 to go to the track saturday. Ive been trying to learn how to tune on a 900whp as my first and wasted a lot of money on the dyno.
Il study up this winter and get back at this meth thing next year.
As for meth dying. Well mine did on a 1000rwhp dyno pull (my pulls are timed 12 seconds on load). When putting the car together I put the meth kit on a 7 amp fuse and forgot. Since my tune is made with the IAT, when the meth failed it pulled timing and added fuel to the point the car stumbled bad. Didn't hurt anything. That was 30 passes ago.
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Mine is commanded 11.0 and with twin 10lb nozzles and pure meth it drops to 10.2. Spraying it 7psi thru 16psi. Not been tuned on meth though. I added myself when I got a wideband to monitor AFR.
If you leaned it out to 11.2-11.5 you would gain a lot of power though.
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I realize this lol but I'm to cheap to go back and my luck it will pop if leaned out. I beat on it every time I drive it and it has been very reliable so far. Just don't want to push my luck trying to get any more out of it. I'm going to see what makes next Saturday at Ticks customer appreciation day. What it makes is what makes lol.
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From: Statesville, NC
Good read here. I'm trying to dial in a 50/50 mix to help with my high IATs (180+) in the 1/4. Slowhawk, I would love to know more about how you setup your "safety features". I know which tables you're referring to but I would like to here from someone who has done it. I am also running the AIS trunk mount kit boost referenced - "all or nothing".
Last edited by Monte4ever; Sep 28, 2013 at 08:54 AM.