Joined
·
639 Posts
Hey dudes, I ran across this aftermarket 'Pegasus' fuel injection system. It has some interesting features I think:
1) 53mm throttle body
2) Computer software to adjust 3D fuel map over any point
3) Sensors only measures engine rpm and throttle position
4) Enrichening circuit for cold starting
5) Controls ignition timing and advance curve (adjustable)
This unit is developed specifically for HD's (what else?) and they say it can deliver 150 HP with certain engines. Pretty impressive with an engine turning under 6000 rpm typically.
Here's the problem... for a single throttle body kit it's about $1500 USD. Not bad, but to use a single body you would need to build a custom intake 'Y' manifold and mount the unit sideways, or underneath the intakes and make it an 'updraft' style. No float bowls, so mounting position is flexible.
It would be cost-prohibitive to mount 2 of these systems on your Triumph twin, and besides...53mm is waaaay too big for a dual TB setup! It is probably OK for a single injector setup though...the throat area of a single 53mm bore is 2206mm2. The area of 2ea 36mm (stock) carbs is 2035mm2. Not a huge increase, but the single is roughly equal to a pair of 38mm carbs.
So, the real advantage would be in near perfect fuel delivery to keep the A/F ratios near ideal at all rpms and throttle openings, while delivering instant throttle response, better HP and torque, lower emissions, better economy and...hmmm, did I forget anything? Oh yeah, you don't have to synchronize the 'carbs' anymore.
Since the system is specifically for HD's I think it would take a LOT of tinkering to make it work on the TT's, unless Pegasus would be willing to work with making it fire with 360 deg and 270 deg versions of our twins. The manifold could be worked out I believe, by branch sizing to maintain velocities that deliver the fuel/air to the cylinders evenly, and with very little loss.
Any thoughts? Someday...someone will make a 'universal' throttle body injection kit for older singles, twins, triples, and fours that we all have and love to play around with. It will never be 'cheap', but hopefully the advantages will make it worthwhile.
Cheers!
BLIGHT:motorbike:
1) 53mm throttle body
2) Computer software to adjust 3D fuel map over any point
3) Sensors only measures engine rpm and throttle position
4) Enrichening circuit for cold starting
5) Controls ignition timing and advance curve (adjustable)
This unit is developed specifically for HD's (what else?) and they say it can deliver 150 HP with certain engines. Pretty impressive with an engine turning under 6000 rpm typically.
Here's the problem... for a single throttle body kit it's about $1500 USD. Not bad, but to use a single body you would need to build a custom intake 'Y' manifold and mount the unit sideways, or underneath the intakes and make it an 'updraft' style. No float bowls, so mounting position is flexible.
It would be cost-prohibitive to mount 2 of these systems on your Triumph twin, and besides...53mm is waaaay too big for a dual TB setup! It is probably OK for a single injector setup though...the throat area of a single 53mm bore is 2206mm2. The area of 2ea 36mm (stock) carbs is 2035mm2. Not a huge increase, but the single is roughly equal to a pair of 38mm carbs.
So, the real advantage would be in near perfect fuel delivery to keep the A/F ratios near ideal at all rpms and throttle openings, while delivering instant throttle response, better HP and torque, lower emissions, better economy and...hmmm, did I forget anything? Oh yeah, you don't have to synchronize the 'carbs' anymore.
Since the system is specifically for HD's I think it would take a LOT of tinkering to make it work on the TT's, unless Pegasus would be willing to work with making it fire with 360 deg and 270 deg versions of our twins. The manifold could be worked out I believe, by branch sizing to maintain velocities that deliver the fuel/air to the cylinders evenly, and with very little loss.
Any thoughts? Someday...someone will make a 'universal' throttle body injection kit for older singles, twins, triples, and fours that we all have and love to play around with. It will never be 'cheap', but hopefully the advantages will make it worthwhile.
Cheers!
BLIGHT:motorbike: