Engine and Engine Mods


What fuel processor should I get?

I have modified my fuel injected Vulcan's intake to increase airflow. Do I need an after market computer to help the stock Electronic Control Module (ECU) modify my air/fuel ratio?

In a word, yes if you want your engine to run efficiently (ok, that's several words) but many Vulcan owners have put their 1500/1600's on dynos and discovered the engine will 'not' run destructively lean even without one.

Assuming you want your engine to idle smoothly and run most efficiently at higher speeds you need to decide which of several devices you want to use. That's going to depend a lot on the depth of your pocketbook and exactly what you're expecting from your engine.

So which of the three most popular after market units do you want/need?  Read the following and choose the one that best fits your personal needs and pocketbook.

Power Commander (PC) was on the market first and is by far the most flexible of the three. With a good dyno operator the PC can be tuned every 250 rpm for the optimum fuel/air ratio and each cylinder separately! That's terrific if you'll be racing your bike or need every ounce of torque you can get all through the power band. In some situations the mixture might actually have to be leaned out to be optimal, others it'll need to be richer. The PC can do all that. There's a price and it's in dollars. The PC is usually the most expensive of the bunch and to take full advantage of it you'll need a lot of time on a dynamometer. That could add up to big bucks and you'll probably need another rear tire when the session is over.

TFI was the next kid on the block. The claim to fame here is its ease of adjustment and low initial cost compared to the PC. The TFI manufacturer also claims this unit actually responds to engine load while the PC is completely RPM based. Whatever, it is simple to adjust, anyone with a small screwdriver and an ear can do it. Of course you can fine tune the mixture using a dyno but this unit can only make the mixture richer, never leaner than the stock ECU so you might not have optimum settings at all rpm in all situations. All the TFI really requires is that you ride the bike a couple of hours and occasionally stop to tweak the settings until you have it dialed in.

Cobra FI2000 This unit seems to be very similar to the TFI. Where the TFI uses four pots to adjust idle, acceleration, high speed and cut in point for the 'main' jet, the Cobra uses three pots so may be even simpler to adjust. Pricing is generally about the same as the TFI.

If you want to know more, check out this website which actually tested the three units and came to some conclusions.

Last Updated: Thursday, August 09 2018 @ 10:48 AM PDT

Was this article helpful?