polarisman14 Posted October 18, 2015 Report Share Posted October 18, 2015 (edited) Hey all, Just wondering if there is a basic tuning theory to tuning for methanol injection. This assumes that the injection nozzle is sized appropriately for your horsepower goals, and that you are utilizing a 50/50 mixture of pure methanol and distilled water for injection (rather than washer fluid as there are inconsistencies in what % methanol it is, etc). For example, the Snow Performance Stage 2 MAP system is what I will be utilizing. I had the same system in my Focus and was very happy with its performance so I'll be going with it again. Kicking myself for selling it as I had the 7qt reservoir and everything. They suggest tuning the controller to start spraying at 1/3 of your peak boost pressure and obviously max out at peak boost. The controller has 2 sets of adjustment screws to dial in when it kicks in and when it maxes out. Assuming all of this is set up properly, what would you use as a new target AFR on meth + 93oct pump gas, and how would you adjust timing? Given that the water in the mixture cools the IATs down and the methanol raises the effective octane rating of the fuel, I would imagine you could run a couple degrees more timing advance without concern for detonation, correct? It seems like timing has a bigger impact on power levels than AFR (within reason, you don't want to be running 10:1 or 14:1 at 20psi) so I would almost leave the target AFRs/VE values alone and just mess with timing instead? Thoughts? Essentially my aim is to make a reliable car that can be used as a daily driver or track day car so I am not looking to run on the ragged edge. Curious if say leaning out the AFRs in boost a few tenths and adding a couple degrees of timing would be safer, or leaving AFR as it and adding 3 or 4 degrees? It's gonna be a while before I get meth installed anyway, but I am curious. I'll either wire the meth in to access table switching when it kicks on or have a low level light installed so I don't beat on it if I run out of methanol...Doing both is probably the smartest for a safeguard. Thanks! Matt Edited October 18, 2015 by polarisman14 Link to comment Share on other sites More sharing options...
Funky Phil Posted October 18, 2015 Report Share Posted October 18, 2015 (edited) tune it so it doesnt detonate and/or quench the spark. 3 or 4 deg is a lot of timing fyi. Edited October 18, 2015 by Funky Phil Link to comment Share on other sites More sharing options...
polarisman14 Posted October 18, 2015 Author Report Share Posted October 18, 2015 (edited) Yeah I was just throwing numbers out. I know there is no "one size fits all" answer that will optimize all setups, just looking for a few guiding principles from people who have tuned successfully using meth as to how their VE table and timing table changed. I've got a better idea of what to do after reading through this thread: http://www.romraider...php?f=33&t=8051 Essentially, the explanation given there is that you use your wideband to datalog the differences in AFR after you install the methanol injection and dial the fuel back so that your new AFR including meth injection matches your targets. You don't really want to lean things out as you are already decreasing the amount of fuel injected to compensate for the meth/water mix contributing to the AFR the wideband sees. You can, however, run 1-2 degrees more timing and a couple psi more boost (generally speaking) which will likely produce ~10% more horsepower and torque. Pump gas with 50/50 meth/water mix is roughly equivalent to C16 in its properties and allows you to tune as such. They consider these to be "horsepower gains" even though they are at higher boost levels, because you wouldn't have been able to run those levels beforehand without detonating. Edited October 18, 2015 by polarisman14 Link to comment Share on other sites More sharing options...
Funky Phil Posted October 18, 2015 Report Share Posted October 18, 2015 No, its far from C16. Those "ratings" are advertising gimmicks. Ive been running methanol injection for 5years on my setup. Link to comment Share on other sites More sharing options...
polarisman14 Posted October 18, 2015 Author Report Share Posted October 18, 2015 So, what benefits do you see when compared to not using it? Sell me on it. What's an honest guy's sales pitch? Link to comment Share on other sites More sharing options...
Funky Phil Posted October 18, 2015 Report Share Posted October 18, 2015 I made 498whp on 30psi and 91oct spraying 75/25. Hows that? lol Heres a post from a little while backhttp://www.sqperformance.com/forum/index.php?topic=320.0 Link to comment Share on other sites More sharing options...
Funky Phil Posted October 19, 2015 Report Share Posted October 19, 2015 (edited) Use it as a safety net and itll work. Use it as a crutch and your motor will not last. Edited October 19, 2015 by Funky Phil Link to comment Share on other sites More sharing options...
polarisman14 Posted October 19, 2015 Author Report Share Posted October 19, 2015 (edited) That's what I am planning on doing. Just trying to get the info out there so other people in my situation will have an easier time finding the info. My take on it based on what I've read and heard is what you said--don't use it as a constant, only as a failsafe. If my AFR at WOT on gas is set to 11.0 and meth drops it down to 10.5 I may tune it back up to 11.0, that'd mean if the meth wasn't spraying anymore it'd be 11.5 and IMO that's still a safe WOT AFR on 93oct. My Focus was at 11.8 AFR target and that was with a 9.6:1 CR vs the 8.0:1 I have now. Same thing with timing, put another degree in it and call it done--unless you were really close to the edge beforehand, then leave it where it is. Awesome numbers BTW! So in order to get those numbers, did you run meth with no tuning and just up the boost, or did you make adjustments to the tune at all? Edited October 19, 2015 by polarisman14 Link to comment Share on other sites More sharing options...
Funky Phil Posted October 20, 2015 Report Share Posted October 20, 2015 You have to acknowledge ign/knock functions which you dont have. People say they did this or that on their modern stock ecu cars that make adjustments for knock. You might add a 3-4deg max target but allow the ecu to pull it back if knock is detected. So what your focus did or someones camaro is irrelevent if your not also monitoring knock. Audible knock is long past too much. Get on a dyno that has a load cell. Thats your answer. The hotter the day, the better. Link to comment Share on other sites More sharing options...
polarisman14 Posted October 20, 2015 Author Report Share Posted October 20, 2015 (edited) The factory knock sensor on the Focus is notoriously unreliable and pulls timing on the stock map due to false detonation, never mind one that is modified--that feature was turned off. I did, however, plumb a stereo output out from the knock sensor wiring and plug it into the factory stereo so I could "hear" what the knock sensor was hearing and listen for what would typically be inaudible detonation. I will likely be having the car tuned on a dyno by a professional in the future anyway--just looking for some guidelines to get the ball rolling a bit in the meantime without putting the car at any real risk. It sounds like the best way to do that for someone who hasn't tuned much is just to install the meth and leave it as is or at the most set the AFR conservatively, so that if the meth system were to fail or run out of fluid it'd still be in the safe range. Edited October 20, 2015 by polarisman14 Link to comment Share on other sites More sharing options...
Funky Phil Posted October 20, 2015 Report Share Posted October 20, 2015 I inject methanol ahead of the IAT sensor. I just set the ECU "IAT related ignition" to pull all the timing out once it sees over 110F. It basically goes off like a soft cut limiter if you set it agressively enough. Dont mess with the table switching. Your just complicating things. Theres no point since your methanol doesnt start until a certain pressure anyways. I aim for the same afr target I do without methanol injection. I give it timing if it wants it and just boost the s*** out of it. But, if your just racing JZ cars you dont need it anyways. Be careful with the low level sensors. Some allow it to shut down the system if it senses its low. The sensors have a tendency to fail even on a full tank. If youve used the systems before, then you know how little you burn. Not difficult to visually check it. If you intend to use the low level sensor and run a boost control like AEM truboost, you can use it to turn the controller off as well. So if meth is switched off, so is your boost. Link to comment Share on other sites More sharing options...
polarisman14 Posted October 20, 2015 Author Report Share Posted October 20, 2015 Yeah I have a TurboSmart Eboost2 electronic boost controller that can do all sorts of things--I haven't wired any of the real capabilities of it in yet but I am sure that is one of them. More than anything I just wanted a low level light on the dash or something to give me a visual cue of when I should be taking it easy. I like your idea of having the boost controller cut the boost for you but it won't retard the timing, either I would have to put that into the MS programming somewhere or just leave the timing alone. Thank you for your input--now I just gotta come up with a few hundred bucks to actually buy it. Really, really kicking myself for selling it in the first place! Link to comment Share on other sites More sharing options...
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