Running lean on meth/ water
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Running lean on meth/ water So I bought a snow performance meth kit for my ly6/whipple 2.9. They told me to have it come on@7lbs and all in @10. So I get on it and my afr is at 14.8? My car is tuned pretty rich , 10.8-11.0 @ wot usually. Map sensor getting wet? . So the car will run leaner for a while, then seems to return to normal.
I like to come in around 6-8psi and be all in around 13-15psi. Progressive is smoother and easier to tune in my opinion. But this depends on how much boost your running. Lets say your only running 10psi, then you cant do a whole lot more than you are now. I would start at 5psi and be in at 9psi if it were a 10psi max.
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Well they initially told me start @8 and all in@10. I bumped it down to 7. Something about a PD blower making boost so quickly. I've been thinking of 12lbs, but I'm scared of hurting it. (60k stock bottom end) I also was watching the iat and didn't see much of a change. This was on blue ww w/3 botttles of heet.( supposed to be 50/50)
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Mines full on @ 7-8 PSI with the biggest nozzle they have. No problems.
Turn off the meth and see if AFR goes back to normal. If it does, you probably have an issue in the tune dealing with IATs. Its also possible its misfiring from weak spark, which will cause it to read lean.
Turn off the meth and see if AFR goes back to normal. If it does, you probably have an issue in the tune dealing with IATs. Its also possible its misfiring from weak spark, which will cause it to read lean.
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Originally Posted by truckdoug
you didnt see the IAT's rise?
or you didn't see them become lower than without the spray?
or you didn't see them become lower than without the spray?
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Originally Posted by JoeNova
Mines full on @ 7-8 PSI with the biggest nozzle they have. No problems.
Turn off the meth and see if AFR goes back to normal. If it does, you probably have an issue in the tune dealing with IATs. Its also possible its misfiring from weak spark, which will cause it to read lean.
Turn off the meth and see if AFR goes back to normal. If it does, you probably have an issue in the tune dealing with IATs. Its also possible its misfiring from weak spark, which will cause it to read lean.
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Me too, BR7ef . All they sent me was the 3 and the 5. I should prob get a 6. I don't really care for the controller. It's hard to see during the day, and the boost gauge part displays a dash or a 0. Out of boost. Then when in boost, the number seems to jump around a lot. This was on its virgin cruise so I'm going to re check all my connections this week end and play around with it some more. Joe, what are u running for boost, and timing?
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20 lbs, 12 degrees of timing. When I turn it up to 24 lbs, I drop timing to 10 degrees.
Were you logging IATs? Its very unlikely that the water/meth mixture throws off your AFR more than half a point, let alone 4 full points. Most likely something else involved as well.
Were you logging IATs? Its very unlikely that the water/meth mixture throws off your AFR more than half a point, let alone 4 full points. Most likely something else involved as well.
Thats not enough Meth. at 50/50 you should be at or around 900ml roughly with something like 600hp estimated. But your heat exchanger means your running a water/air intercooler. So your spray is more for detonation control than cooler IAT temps. I was spraying about 750-900ml at only point and saw no drop in IAT temps. Ive sprayed pre SC and pre TB as well. Ive never noticed a decrease in IAT temps when spraying and this is with -20 wiper fluid as well as 50/50 boost juice.
When you run a A2A or W2A you dont need as much meth as its not going to evaporate in the cooler charge as fast and since your IAT temps are pretty darn good to be only 20* above ambient your not really helping the temp as much. Your setup would be better spraying pure meth for the octane boost but pure meth will also absorb much faster even in the cooler charge and you will prob see a decent temp drop.
FWIW I run a 500ml nozzle of 50/50 an have it start at 2pi and full in by 8psi. Reason is I can hit boost really quickly on a small centri and I'm running about 18* at WOT with 10-12psi using the cheapest 93 in town and only street driving so I like it coming on earlier to help with heat soak. Even at my largest nozzle setting I only saw .3-.5:1 drop in WOT AFR.
When you run a A2A or W2A you dont need as much meth as its not going to evaporate in the cooler charge as fast and since your IAT temps are pretty darn good to be only 20* above ambient your not really helping the temp as much. Your setup would be better spraying pure meth for the octane boost but pure meth will also absorb much faster even in the cooler charge and you will prob see a decent temp drop.
FWIW I run a 500ml nozzle of 50/50 an have it start at 2pi and full in by 8psi. Reason is I can hit boost really quickly on a small centri and I'm running about 18* at WOT with 10-12psi using the cheapest 93 in town and only street driving so I like it coming on earlier to help with heat soak. Even at my largest nozzle setting I only saw .3-.5:1 drop in WOT AFR.
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Well it's not exactly a mail order tune. They remotely tuned it based on the same combo( it's their cam) tune is pretty conservative. After I get the meth fig out, I will have it dyno tuned. Needs to be leaned out a little. They told me that.
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Well it seems better. I moved the power wire to a different spot and I think that was half the problem. Custom black bird, I appreciate your response. I think I will switch to pure meth and try a bigger nozzle. I put the 375ml based on snows recomondation. This whole thing is a big learning curve for me. I'm running 93 e-10 and base advance is 14 and final(total )advance is 18 .right now, AFR is 13-13.5 idle 12-12.5 cruise and 10.8-11.0 wot (without meth) I'm running 10lbs boost, but would like to run 12-13 .
be careful pure meth has a very low flash point. I think your better at 70/30 but are you running any form of intercooler? Bc that will affect how much you need to spray.
I just finished my W2A and saw 130-150*F Supercharger outlet temps, 100-120*F IC outlet temps (not sure as they are getting heat soaked alittle bit, but my IATs in the motor were 111-99*F and once the 50/50 was activated it would drop 18* to 82-88*F according to my datalogs. I have to check my nozzle size again but I will see now a 18* drop in a 4s boost pull with just the 50/50 mix. I was at 10psi and 16* at WOT but I should be at 18* but its pulling 2* for knock (I think its false knock)
BTW your 375ml nozzle doesnt actually flow 375 if I remember correctly. Look at snows site, they rate the nozzle flow at a much lower 40psi, so your 375 is flowing a good bit more as most pumps are 150psi+ but if you contact Devils own he will tell you to spray alot more, the snow performance recomendations are conservative.
I just finished my W2A and saw 130-150*F Supercharger outlet temps, 100-120*F IC outlet temps (not sure as they are getting heat soaked alittle bit, but my IATs in the motor were 111-99*F and once the 50/50 was activated it would drop 18* to 82-88*F according to my datalogs. I have to check my nozzle size again but I will see now a 18* drop in a 4s boost pull with just the 50/50 mix. I was at 10psi and 16* at WOT but I should be at 18* but its pulling 2* for knock (I think its false knock)
BTW your 375ml nozzle doesnt actually flow 375 if I remember correctly. Look at snows site, they rate the nozzle flow at a much lower 40psi, so your 375 is flowing a good bit more as most pumps are 150psi+ but if you contact Devils own he will tell you to spray alot more, the snow performance recomendations are conservative.