1991 stock 5.0 on3 turbo megasquirt tuning.

[Scrappy91]

So I’m trying to tune my car with the mspnp2 it’s a stock 91 with a c4 and a on3 turbo kit with ford 47lb injectors and I’m having a really hard time getting it to stay running and I can’t get it to idle any advice would be appreciated

 

[a91what]

So I’m trying to tune my car with the mspnp2 it’s a stock 91 with a c4 and a on3 turbo kit with ford 47lb injectors and I’m having a really hard time getting it to stay running and I can’t get it to idle any advice would be appreciated

getting the injector and idle settings correct can be tricky. This tune file should be close to what you need if you are running FRPP lu47 injectors. I usually dont give complete tunes away for free.
Getting a good idle starts with having the timing and fuel set correctly, on a 5.0 an idle AFR of 13.5-14.2 is usually good with 18-22* of timing a steady idle should be attainable with the IAC valve unplugged.
Make sure you have your sensors calibrated and you will need a wideband of course.
Load this tune and datalog it I can help you from there.

 

[Scrappy91]

getting the injector and idle settings correct can be tricky. This tune file should be close to what you need if you are running FRPP lu47 injectors. I usually dont give complete tunes away for free.
Getting a good idle starts with having the timing and fuel set correctly, on a 5.0 an idle AFR of 13.5-14.2 is usually good with 18-22* of timing a steady idle should be attainable with the IAC valve unplugged.
Make sure you have your sensors calibrated and you will need a wideband of course.
Load this tune and datalog it I can help you from there.

Thank you i will load it up tomorrow and post results

 

[Scrappy91]

Do i need to unplug my iac

 

[a91what]

Only if you experience bad idle oscillation (surging) idle settings are not one size fits all, what works on one car may be different for another even with the same parts.

 

[Scrappy91]

getting the injector and idle settings correct can be tricky. This tune file should be close to what you need if you are running FRPP lu47 injectors. I usually dont give complete tunes away for free.
Getting a good idle starts with having the timing and fuel set correctly, on a 5.0 an idle AFR of 13.5-14.2 is usually good with 18-22* of timing a steady idle should be attainable with the IAC valve unplugged.
Make sure you have your sensors calibrated and you will need a wideband of course.
Load this tune and datalog it I can help you from there.

i loaded the tune and had to mess with the timing a little to get it to idle it goes way lean when i rev it i also forgot to mention i have a walboro 255 fuel pump here is the log . thanks in advance

 

[a91what]

i loaded the tune and had to mess with the timing a little to get it to idle it goes way lean when i rev it i also forgot to mention i have a walboro 255 fuel pump here is the log . thanks in advance

Do you know how to properly set the timing with MS? I will look through the file when I am back in civilization, camping now.

 

[Scrappy91]

Do you know how to properly set the timing with MS? I will look through the file when I am back in civilization, camping now.

im not sure is it by setting it to fixed timing and making sure that the timing on tuner studios is the same as it is at the crank

 

[a91what]

im not sure is it by setting it to fixed timing and making sure that the timing on tuner studios is the same as it is at the crank

Basically yes.

 

[Scrappy91]

i have a 1991 mustang with stock 302 all that is done to it is a walboro 255 fuel pump, ford lu47 injectors, c4 trans, and a on3 turbo kit. havent got to drive the car yet because it goes lean when i rev it and it wont go past 3k . any help is appreciated

 

[5.0Thunder]

Scrappy, I'll try to grab these files and take a look soon.

 

[5.0Thunder]

So there definitely needs to be some work done to the tune. The fuel table was pretty crazy down low, no way you'll get a stable idle with that. I realize Steve may have started working on this tune so I'll let him keep it up.

 

[a91what]

Ok not much i can do right now with the datalog and file, i could smooth out the craziness in the fuel table but i will refrain from touching anything until we get a useable o2 signal. What WB are you running? you need to calibrate it under the tools menu, right now we are only seeing a raw o2 voltage input. MS cannot use this for EGO feedback unless you do the setup in the tools menu, I could make megalog viewer interpret the data if i knew which WB you had.
You need to do this before we can move on.

 

[Scrappy91]

i have a
AEM (30-4110)

 

[Scrappy91]

Ok not much i can do right now with the datalog and file, i could smooth out the craziness in the fuel table but i will refrain from touching anything until we get a useable o2 signal. What WB are you running? you need to calibrate it under the tools menu, right now we are only seeing a raw o2 voltage input. MS cannot use this for EGO feedback unless you do the setup in the tools menu, I could make megalog viewer interpret the data if i knew which WB you had.
You need to do this before we can move on.

i have messed with the tune alot since i posted i have it able to idle ok ill will post the msq and a new data log tomorrow

 

[5.0Thunder]

Is the wideband properly calibrated now i'm guessing?

 

[Scrappy91]

what is the exhaust gas oxygen gauge it seems to be kind of bouncing around.

 

[a91what]

That gauge can be changed to a AFR gauge, you can right click it and choose a new one. the exhaust gas oxygen gauge is reading the voltage from your O2 sensor.
Did you ever get the WB calibrated in TS? do you know how? Is there anything you need explained to you?- settings, tables ect.....

 

[Scrappy91]

That gauge can be changed to a AFR gauge, you can right click it and choose a new one. the exhaust gas oxygen gauge is reading the voltage from your O2 sensor.
Did you ever get the WB calibrated in TS? do you know how? Is there anything you need explained to you?- settings, tables ect.....

i did get the wideband calibrated i want to redo the ground since i have it grounded to the battery what would the best spot to ground it be. thanks for the help

 

[a91what]

Best option is to ground it at the ECU. Most of the wb manufacturers have different guidelines some say at ECU other like innovate say ground at battery.