Time to get Pimpin"

[General karthief]

What does it mean when this happens?

it means you have to wait 16 minutes before you can start it.

 

[Noobz347]

it means you have to wait 16 minutes before you can start it.

Oh

I thought there would be more

 

[a91what]

What does it mean when this happens?

A few things, the main concern is the MAT or IAT sensor heat soaks with a lack of air transfer around it... that is until the engine is pumping again, this causes the MAT correction [remember SD uses MAT temps in the air density equation] to become lean on HOT start. To properly correct this without altering the running fuel correction [ this means we do NOT want to alter the MAT correction table after we are done tuning as this will require further fuel trim in the main table] we will go in and add fuel in a percentage to offset the sensor soak for the first minute of startup. We will do this in the ASE and ASE taper tables [after start enrichment and taper 'how long the ase stays in effect'] properly set the engine will not experience any lean condition at startup, as a driver you would not even notice it could be an issue.

 

[Noobz347]

A few things, the main concern is the MAT or IAT sensor heat soaks with a lack of air transfer around it... that is until the engine is pumping again, this causes the MAT correction [remember SD uses MAT temps in the air density equation] to become lean on HOT start. To properly correct this without altering the running fuel correction [ this means we do NOT want to alter the MAT correction table after we are done tuning as this will require further fuel trim in the main table] we will go in and add fuel in a percentage to offset the sensor soak for the first minute of startup. We will do this in the ASE and ASE taper tables [after start enrichment and taper 'how long the ase stays in effect'] properly set the engine will not experience any lean condition at startup, as a driver you would not even notice it could be an issue.

I believe that this is an issue with the current chip-tune on my 86 (MAF).

 

[96pushrod]

A few things, the main concern is the MAT or IAT sensor heat soaks with a lack of air transfer around it... that is until the engine is pumping again, this causes the MAT correction [remember SD uses MAT temps in the air density equation] to become lean on HOT start. To properly correct this without altering the running fuel correction [ this means we do NOT want to alter the MAT correction table after we are done tuning as this will require further fuel trim in the main table] we will go in and add fuel in a percentage to offset the sensor soak for the first minute of startup. We will do this in the ASE and ASE taper tables [after start enrichment and taper 'how long the ase stays in effect'] properly set the engine will not experience any lean condition at startup, as a driver you would not even notice it could be an issue.

The only way I was able to fight this was to alter the mat temp table. Didn’t take much, just a bit of adjustment

I ended up changing over to a gm intake air temp sensor as well, and moved the sensor away from the #5 runner and into the upper intake plenum.

 

[Mstng93SSP]

It gave a little trouble on the heat soak restart, nothing huge, but noticeable. I am about to go do the cold start and data log. I will also data log a heat soak restart later. Gonna go drive my car now

 

[a91what]

The only way I was able to fight this was to alter the mat temp table. Didn’t take much, just a bit of adjustment

I ended up changing over to a gm intake air temp sensor as well, and moved the sensor away from the #5 runner and into the upper intake plenum.

Altering the mat air density curve is sometimes a necessary evil... different intake, sensor arrangements may even need different curves, especially if the sensor placement was altered.

 

[Noobz347]

The only way I was able to fight this was to alter the mat temp table. Didn’t take much, just a bit of adjustment

I ended up changing over to a gm intake air temp sensor as well, and moved the sensor away from the #5 runner and into the upper intake plenum.

I installed a hi torque starter

 

[Mstng93SSP]

@a91what I just emailed you a few data logs.

Thanks

 

[a91what]

I assume cold start needs work? How did it drive today?

 

[Mstng93SSP]

Let me know if you got my email? I can't find it in my sent file? Cold start actually wasn't bad at all. Hot start, it doesn't like hot start too much. This was cold start.

 

[Mstng93SSP]

And hot start.

 

[a91what]

No i did not recieve an email.

 

[Mstng93SSP]

I will try to send it from my other email account.

 

[a91what]

Ok details on hot start, long crank or start and die/ stsrt and lean surge?

 

[Mstng93SSP]

Start and die. Had to crank a couple of times and then had to hold to the floor to start followed by a rough idle for a bit.

 

[a91what]

ok so EGO correction at idle is causing some oscillation, I am going to slow the correction down first if that does not do it then i am going to shut it off at idle completely for now.

Hot restart looks terrible, I cant figure out if it needs less cranking fuel or more idle valve based on the log file.. so i am going to increase valve duty first and make no fuel adjustment for this first revision.

 

[Mstng93SSP]

 

[a91what]

REV 1.0.2 should be in your inbox, I left some instructions in the email.

 

[Mstng93SSP]

Got it. Will let you know. Thanks again Steve. I appreciate it.

Chris