I have a 99 Roadking - with SE high flow kit, SE slip ons and S&S 510 CAM. Since the cams were installed the bike is virtually unrideable once hot. All the advice is to upgrade the MAP. The PowerCommander is a cheaper option - but I'm also very interested in the ThunderMax MM EFI conversion - albeit without the auto tune. Has anybody had experience with this config. Or should I simply go for the PowerCommander at approx 2/3 of the ThunderMax price. Thanks,

 

Describe unrideable.

Did you have a stage 1 or 2 loaded to your ecm. If not you are too lean. Put the stock air breather box and filter back on and see if it becomes more rideable.

You can also advance the throttle position sensor to enrichen the low and mid range.

Power Commander 3 USB works well with the M/M system.


2000 RK
95" TW 21 cams
Bub 7 2 into 1
Ported and decked heads
PC 3 USB with AFR meter to allow tuning
Stock breather box with K&N filter

 

I would go with the PC III serial or USB, a huge library of maps available for MMs. The serial version can be found on such places as Ebay, much less expensive and will do the job if you have a serial ported laptop or a USB/serial converter.

Keep in mind, advancing the TPS sensor will enrichen fuel but also retard timing, good for experimenting providing you can get it set back to exactly were it was if needed.

 

How does advancing the throttle position sensor retard the timing?

 

The MM system uses throttle position to determine the engine's load for a given RPM. As the TPS signal (load) increases, the fuel table increases fuel and the timing table decreases spark advance. The old MM system is a full Alpha N (TPS based) engine management system, meaning that it uses a TPS position for both fuel and spark. The newer Delphi system uses TPS for fuel, but instead, a MAP sensor for spark timing. As manifold absolute pressure (load) increases, spark timing decreases at a given RPM. The Delphi is a half Alpha N and a half MAP based system. So with the MM, unlike most other systems, moving the TPS sensor changes fuel and spark.

 

Ok, that sounds good. However I only move mine toward the maximum variations allowed in the SM.