The more I read about EFI tuning the more confused I get. I have been reading about EFI for two days trying to figure out which tuner I need for my '08 Deluxe. I am switching my air filter to a S&S air filter and plan to switch add a set of V&H (Long or Big Shots) exhaust. I had orginally figured that I would get a V&H Fuelpak to adjust the engine. But after reading for two days I am not sure if this is the best thing for me to do.

I have always figured that I can hold my own with working of vehicles but messing with EFI is a little out of my element.

 

Making matters worse is the number options to choose from! SERT, TTS, PC5, Thundermax, etc. Who is going to do the work? I would think an important part of the decision would be to use the system that the tuner has a lot of experience with.

 

I have always done all my own work so I will be doing this also.

 

Ask yourself this one question... Do you plan on EVER doing anything to the engine, etc? Do you plan to try to increase power a little as time goes on? If the answer is 'yes' do a favor and buy a TTS. If the answer is 'no' buy a PC5 from Fuelmoto and get a canned map. The power commander line is good for Stage 1's, except for some loss in fuel mileage. The TTS is the best platform to adjust the tune to YOUR bike and how it is exactly set up.

Tmax is good for older bikes, but I feel it is a step BACKWARDS for a newer model bike as the TMax does NOT monitor load placed upon the engine and adjust fuel and timing for that load. Also, ALL of the power commanders tend to be a less sophisticated fuel method as they 'add on' to the existing structure inside of the ECM itself, so why not adjust the ECM directly, right? So... that leaves the SEPST, TTS and PC Vision.

For a "do it yourselfer"... TTS will be the best choice as the SEPST will change values when inserting into the ECM with OUT you permission. And the Vision uses faulty data at times. TTS is WORK, but once on figures it out, not so bad.

Your choice!

 

Wrong. No system will measure actual engine load as a H-D is an Alpha-N design. A Harley does not have a mass air flow (MAF) sensor like my Toyota cage does, so to measure engine load the tuner - whether a T-Max or TTS or whatever - has to use throttle position (TPS) plus RPM. The reason why Toyota does not require a re-tune when adding TRD components like exhaust, headers, intake, supercharger, 7th injector, etc. is because it has a MAF sensor.

 

Nope, the HD system is speed density. It doesn't have a MAF sensor as the intake is too short but it does have a MAP sensor. The Tmax is Alpha N, tps/rpm.

 

Are you saying T-Max does not use the MAP sensor data for computation of fuel/timing, but TTS does?

 

Not that familiar with the Tmax but I know they have added a map funtion to it. The older calibrations use map for afr and timing. The newer lambda calibrations also use it for the ve tables.

 

VE being volumetric efficiency? I thought lambda is an AFR calculation - basically, that is what the O2 sensor is telling the ECM. What is the relationship between lambda and VE?

 

The fuel pak is a pos. Don't waste a dime on that.
I have a pcv. I don't know what the guys up there are saying about fuel consumption but I get over 40 mpg easily on the highway. I'm happy with it.