Feedback: Fuel Pak verses Power Vision
 

This write-up is part two of an experiment comparing the performance of the older Vance and Hines Fuel Pak against the Dynojet Power Vision. It has always been believed that the Fuel Pak can not properly manage fuel delivery for any modification other than Stage 1. My experiment was an attempt to verify, or dispel this theory.

The bike is an 02 Fatboy, (Open Loop EFI). For many years I ran a Stage 1 tuned with the V&H Fuel Pak. I recently installed a set of Andrews 21 cams. I had a Power Vision sitting on my parts shelf but as an experiment and for my own curiosity, I attempted to dial-in the fuel management with the Fuel Pak. Vance and Hines assured me that it could be done and that the Fuel Pak could be modified to perform properly with aftermarket cams. V&H provided me with initial settings however the engine stumbled when accelerating from low rpms, just off idle up to 2,500. Contacting V&H, they provided changes to three modes which solved this problem. After making the changes, the bike ran flawlessly. It accelerated hard throughout the rpm band with no hesitation or decel pop. The AFR was however slightly lean and the engine ran hot and reached extremely high temps when idling in traffic. V&H again offered mode changes which enriched the AFR. These additional changes cooled the engine down however I experienced a slight decrease in performance and acceleration.

After many conversations with V&H, many adjustments to the Fuel Pac, and many test rides, I concluded that I reached the limits of the Fuel Pac and decided it was time to swap to the Power Vision.

Dynojet has numerous pre-programed (Canned Maps) for various applications however none were designed for my Stage 1 with aftermarket cams. Dynojet did write a custom map for my specification. The procedure involved connecting the Power Vision to the bike, retrieving the stock Map, transfering it to a computer using the PV software and forwarding it to Dynojet as an email attachment. Within 24 hours I received the custom Map from Dynojet and after loading it into the Power Vision, I flashed the ECM. Hitting the start switch, the bike fired up immediately. Test rides have been positive. Smooth, hard acceleration. No hesitation, or deceleration pop and engine temps are within acceptable limits. The only anomaly is that occasionally when coming to a stop, the engine idles high at 1,200 rpms. This corrects itself after roughly 2 minutes. Since I have an Open Loop system I'm unable to take advantage of the Auto Tune feature of the Power Vision but the unit has many manual tweaking capabilities with I'll experiment with.

Test Summery:

(1) The V&H Fuel Pak can in-fact be set up to perform past a Stage 1 however my testing results conclude that it cannot provide the best fuel management for modification other than Stage 1.

(2) The Dynojet Power Vision properly manages fuel for modifications past Stage 1 and the performance of the Power Vision has, within my experiment, greatly surpassed the performance of the Fuel Pak.

Vance and Hines is a solid company producing quality products and has a great customer service department. Their older version of the Fuel Pak is an easy inexpensive method to manage fuel with a Stage 1 however it cannot compare with the performance benefits of the Power Vision when adding aftermarket cams. I wish them luck with their new FP3.

After using a FP on my Sportster and now using a PV on my Softail, I agree with everything you said above.

No matter which tuner you eventually decide upon, there will always be someone along shortly who will tell you how wrong you were in your decision, and that you should have done what they did - for the same money.

That being said, I went from a dealer "remap", to an H-D SEPST, to ViED's, to a V&H FP3.
The FP3 has surpassed all my expectations and my bike has never run better.