RPM's settings in a Thrasher92 Chip

[Danster]

Can someone tell me if the RPM's are controlled by the chip and is so what would be the setting in a Thrasher92 chip?

Thanks!


Dannyo

 

[Scott231]

RPMs are controlled by your foot position in relation to the load on the motor...

 

[Danster]

I guess what I'm trying to say, what controls the rpm's at idle (park). Still learning on the cars and chips.

Thanks!

Dannyo

 

[TT/Ameasap]

I think your talking about the TPS.(Throttle Position Sensor)

 

[Danster]

I don't think it's the TPS. I just want to understand what in the car controls the RPM's at idle???? I know not all our cars do not idle at the same RPM reading.

Dannyo

 

[Black Car]

Dannyo,
There is an idle speed for neutral & in drive in the chip program.
Not 100% positive but I believe that Thrasher uses the factory setting of 650 to 675 RPM.

Gary

 

[Danster]

Thanks Black Car!

I just wanted to make sure I understood where the RPM's were being controlled.

Dannyo

 

[Scott231]

When the car is first warming up, it is running in Open-Loop mode and the ECM doesn't accept inputs from the sensors. As such, the injector pulsewidth and the ignition timing are determined based on the Open-loop data on the chip. It does however try to achieve the desired RPM speed at idle (which is a table on the chip (RPM vs. temp) using the Idle Air Control Motor.

Once the engine is up to operating temperature, the ECM switches to Closed-Loop mode and begins adjusting the fuel mixture and ignition timing based on various inputs from the multiple sensors on the car. The IACM is still used, but now you have multiple parameters being adjusted to attain the chip's requested idle RPM.

This is common to all chips, not just Thrashers.

 

[blackbuick87]

I thought the Thrasher did not go into closed loop but stayed in open loop.

 

[Scott231]

Nope. Runs mostly like a stocker "Loop-wise" except for the fulll-time Open-Loop mode idle.

You have the option of removing the O2 sensor and running the Thrasher. The chip is designed to identify the sensor as missing and running in full time Open Loop.

 

[blackbuick87]

Do they usually run better that way? Since I have leaded 110 in the tank right now I think my days are numbered on this o2. Maybe I will try it with just unplugging the sensor. Does the chip recognize this immediately and will the computer throw a code?

 

[VIN7]

I'd be better if you "learned" the blm tables with 93 octane and a good 02 sensor. With the 02 sensor removed the Thrashers doesn't "code 13", it switches to open loop and uses the "learned" blm values.

Mike