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I finally got my car to a Tuner but I'm not sure I can trust it. Can you guys look at the tune file to see if you see anything wrong. This is a Methanol car incase all the AFR-s look funny. It has not been to the track sense the EFI was installed.

Attached Files

File extension is.msq

What program to open it with?


.msq is opened with Tunerstudio, the Megasquirt software.


In order to help, it would be easier if you tell us what car and engine it is, and how will the car be driven, race car, street car? Is there any reason why you shouldn't trust the tune? Are there any signs that it is off, like in driveability?

This is a drag car 383 glide 4.88 gear. This is a relatively new engine which I have had problems with sense I put this EFI system on it. The last thing I need is a bunch of melted pistons because of a tune that I know nothing about as I couldn't figure it out, so paid for someone to do.

Open with Tuner studio the Megasquirt software.

Hi Michael, in order for us to give feedback we're going to need a specific area of your tune that you're concerned with and even better if you have a log file demonstrating what you're worried about. I've been tuning for the better part of 30 years but still couldn't just take a look at a calibration with no more info and say with authority if it's good or bad. The other problem with us being able to offer any meaningful feedback is without a log file showing mixtures etc, we're blind as to how the engine is actually running, which is really the important part.

So if you've got a specific question or concern then please give us more info so we can help you out.

My concern is there is no heat building in the engine. Watching the engine the cooling fan never came on. The ecu is set to turn it on at 180° far as I can tell it only gets to 158°. Another thing is Lambda is .5 but AFR is 10. Remember now this is a Methanol fuel. I am missing something or just confused. Attached is the log file for this tune. Sorry for all the confusion.

Attached Files

A lot of engines make best power between low 60s and 70s Celsius, on methanol I imagine there is a lot less relative heat transfer to the block fir delivered power as the oxygen an a portion of the hydrogen in the methanol is effectively a total loss coolant. I would fit as low a temperature thermostat as you can buy and set the fan if electric a few degrees about that nominal temperature. 90-100C target coolant temperatures on modern cars is about emissions reductions.

So to be clear your saying 158° is a ok temperature and I should set fan for say 165°. I do not have a thermostat. The coolant is moved by an electric pump and the plumbing has been reversed to push coolant to the heads and hot water out the block. When I was running Gasoline the engine would heat up to much so reversing the coolant flow helped with that problem. Having never run Methanol the temperatures seem to low. I will try that and see how that works. Thanks for the tip.

My 10 cents worth.

Unless you have the AFR calibrated for methanol, it's not going to mean much. It's easier, and certainly more useful with different fuels, to use the lambda values, this is what the EFR gauge uses to calculate the value, anyway. FWIW, stoich' for methanol, lambda 1.0, is approximately a true 6.5:1, if using a gauge calibrated for petrol/gasoline, that'll show as approx' 14.7:1 - which is why you need to be very careful talking about AFR with different fuel - there's true, and there's what the gauge says.

For a N/A engine, most seem to suggest running around a true 5:1, or around lambda 0.8, IIRC. Methanol is very tolerant of very rich mixtures, as far as 0.5 in some cases, and can be run quite lean, more than lambda 1.2, but I understand that's maybe not too wise.

I don't know how accurate your figures are, but while 0.5 may "work", it's usually used for charge cooling with high boost engines - the large volumes of fuel used have a considerable evaporative cooling affect - and because the richer burn will be much cooler than with gasoline. There isn't that much power loss, but the real problem is liquid methanol washing the lubricant from the bores, with resultant ring and bore wear issues, and oil dilution can be a big problem because large volumes of fuel can bypass the rings, which mens frequent oil changes may be wise.

Both those last factors are why it can be difficult to get the engine "hot", and why it's normally used for specialist "burnout" cars to prevent them overheating. It may also be why you can't get any heat into the engine - you should find running a lambda of around 0.8-0.85 gives more power, a bit more heat, and improved ring and oil life.

Did you look at the log file above? I believe I set it to Lambda but was unable to get the AFR to read what the lambda values were in tuner studio. Do you have any thought on that?

Taking a very quick look at the log you're running way rich over the target, it looks like the sensor is pegged out, is it a Bosch LSU sensor or NTK sensor you're using?

As it's been said, running overly rich in a methanol engine you'll run a lot colder.

To elaborate on what I said, the lambda value is directly referencing the oxygen content in the exhaust gas, this is what is given to the gauge, or other device, that displays the AFR, with it being converted internally. For the same value of lamda, for example 1.0 which is stoichometric (chemically balanced), the TRUE AFR for different fuels will vary greatly, from as low as 6.5:1 for methanol to gasoline's 14.7:1, but unless the gauge is calibrated for the fuel and is still set for petrol/gasoline it will still show 14.7:1.

For this reason, it's usually much better practice to just use lambda, especially with fuels containing any alcohol blends.

You may find this chart handy - https://ftyracing.com/tech/lambda-afr-table/ - to illustrate this, and if you print it off, and the gauge can't display lambda (some have a switch somewhere), you can use it as a cross-reference between what it's reading and what the AFR for the fuel you're using actually is.

Chris I have New LSU 4.9 O2 sensors, powered by Holley. Gord I don't have an external gauge for AFR the ECU MS3 Pro is doing all the reading. Like I said I have changed in tuner studio fuel type to methanol and fuel table to Lambda. Would those items be in the tune file? I don't remember a place to change AFR or changing the numbers. I do have the Lambda -AFR- Table to reference. But on the dash you see AFR displayed as for Gasoline. To get the right figures I have to go to log file see what the ECU says Lambda is then go to table to get the AFR numbers. Not ever using the Lambda values before has got me confused where as seeing the actual AFR numbers sort of rights it in my mind. Once I get to using the Lambda values more often it will be second nature. Right now I'm lost in space. Thanks for the help fellows I apreciate it.

I haven't used that ECU platform, and checking this quite comprehensive guide - https://www.ampefi.com/wp-content/uploads/ms3pro_ultimate_manual.pdf - there doesn't seem to be a way of changing the AFR display to reflect the fuel used, but I could very well be mistaken, quite likely so, TBH :-)

Forgot to mention - methanol is a very 'nasty' fuel and will disolve most seals and rubbers that aren't designed to handle it, and with aluminium, zinc, and some other metal based alloys, when there's any water in the methanol, it will strip the protective oxide surface coating and allow rapid disolving of the metal as the surface is eaten away by corrosive reactions.

It's be a smart move, if you haven't done it, to review EVERYTHING in the fuelling system that has any contact with the fuel to make sure it's compatable.

Even then, it's usually a good idea to flush with ethanol after using the vehicle, or at least draining it.

Yes that has been a prime concern All fuel lines, pumps (3), Fuel tank (Stainless), Are compatible with methanol. I have also added a temp sensor in the oil pan to make sure there is enough heat to help extract any methanol or water from the pan. I also send oil off to AMSOIL for examination for contaminates.

TBH ?? I'm 75 my generation is lost with out the actual words. I downloaded a 3 page chart of all the acronyms so I can keep up, TBH is not on the list sorry. Can you imagine reading a instruction manual full of acronyms and not knowing what they stand for? It would take minutes for you, hours for me. That is why us old guys stick to what we know but once we step out of that comfort zone there is a lot of swearing going on. Thanks again for all the help.

TBH = Too Be Honest.

I'll add that to my list. Thanks

My favourite is TLA - three letter acronym.

As another 'old fart', I'd agree that points and carbies are often SO much simpler to work with, especially when there are problems, but overall when the electronics play nice it's a different matter.

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