Side hood intake

If you follow the thread you'll see he has enough dyno runs and hrs of run time for that to not be an issue with the windstar intake. 30 hole injectors? That is definitely something that needs tuning

Thanks. I haven't followed the thread all the way through. Right here, it sounded like @Jezza wasn't going to be able to test again later because other mods would have been made by then.
 
But with these alternative intake systems (whether true CAI or not), has anyone returned to test again after the computer has time to adapt? Over here, that's what I took Blaine to be saying?

The JTEC PCM has no mechanism by which fuel or timing can be modified or learned in power enrichment mode. O2 sensors of this vintage are only capable of accurate values near the stoich range. Therefore it can only learn values at idle and part throttle. Around 75% throttle the PCM enteres power enrichment mode and 02 values are ignored and it runs preset values for fuel. Spark is even more simple. It is base tables+ coolant and intake temp compensation tables = Spark. No knock sensors or feedbacks.
 
The JTEC PCM has no mechanism by which fuel or timing can be modified or learned in power enrichment mode. O2 sensors of this vintage are only capable of accurate values near the stoich range. Therefore it can only learn values at idle and part throttle. Around 75% throttle the PCM enteres power enrichment mode and 02 values are ignored and it runs preset values for fuel. Spark is even more simple. It is base tables+ coolant and intake temp compensation tables = Spark. No knock sensors or feedbacks.

You mean without a tune from hp tuners,etc and a wideband right?

If you could choose an engine management system today for the early tj with boost,stroker,etc for ease of tuning and sensor choice what would it be? At some point oem will be a losing battle
 
The JTEC PCM has no mechanism by which fuel or timing can be modified or learned in power enrichment mode. O2 sensors of this vintage are only capable of accurate values near the stoich range. Therefore it can only learn values at idle and part throttle. Around 75% throttle the PCM enteres power enrichment mode and 02 values are ignored and it runs preset values for fuel. Spark is even more simple. It is base tables+ coolant and intake temp compensation tables = Spark. No knock sensors or feedbacks.

Got it, thanks.

But, does this mean that below 75% throttle, the PCM can and does 'learn'? If so, would any immediate HP gains from a CAI (or from just removing the air filter) possibly go away over time below 75% throttle?

Not trying to quibble—just trying to understand how excited to be about the immediate gains you posted when removing the air filter.
 
You mean without a tune from hp tuners,etc and a wideband right?

If you could choose an engine management system today for the early tj with boost,stroker,etc for ease of tuning and sensor choice what would it be? At some point oem will be a losing battle

Even with a tune and a wideband hooked up the PCM is blind in power enrichment. I run an AEM Infinity with a wideband that is able to correct the mixture under full throttle to whatever ratio I choose. I run the AEM because it's what I know, but there are many other systems that all have good features. I know some of the stroker guys run Megasquirt. I'm helping a guy with a Haltec setup right now. I think Holley has a product that would work, and the list goes on.
 
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Got it, thanks.

But, does this mean that below 75% throttle, the PCM can and does 'learn'? If so, would any immediate HP gains from a CAI (or from just removing the air filter) possibly go away over time below 75% throttle?

Not trying to quibble—just trying to understand how excited to be about the immediate gains you posted when removing the air filter.

Yes, the PCM uses short and long term adaptive fuel trims to adjust the mixture to stoich below the PE threshold. However, if you increase the airflow anywhere in the range below PE the PCM will be forced to add more fuel to match the increased airflow. There may be a case where you add airflow and the engine runs lean for a while making more power, then as the adaptives push more fuel to return to stoich the power would go back down. In almost all cases however, more airflow more power. The PCM has no control over airflow and must match the airflow with fuel when learning.