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Fuel Injection Conversion!

Some of the key features

  • High resolution fuel table mapping
  • High resolution ignition mapping
  • Live exhaust oxygen content monitoring
  • Shift light option
  • Two stage adjustable rev limit
  • Launch control option
  • Knock sensing option
  • Accel enrichment and decay time
  • Trim tables for :
  • Air box temperature
  • Engine temperature
  • Battery voltage
  • Dwell compensation
  • Warm up, fuel and ignition
Jacks new graphics

Besides some of the features listed above the real reason for doing this was to cure the fueling problems you get with a tuned engine.

Firstly to produce good top end power and torque this engine needs a cam with a long duration and so a lot of cam over lap.
One problem with a long duration cam is that the inlet valve is held open longer, so when the piston is on its way back up and your inlet valve is still open you get a unwanted pulse going up the inlet port and over the main jet pulling up more fuel, this extra fuel then gets added to the total fuel being used and you end up with a very rich mixture at low to mid engine speeds.

Depending on your setup this can be a big problem, If you look at the graph below of a typical tuned Raptor you'll see the many problems your trying to deal with.

Carb Air/Fuel Ratio Graph

You can see at 3000 to 7000 its seriously rich then at 7500 (peak torque) its on the lean side losing power and possibly causing detonation, after that 8500 and its about right for a short time before heading south again and spoiling the last 1000 rpm.

EFI Air/Fuel Ratio Graph

Now looking at the injected engine, No problems anywhere, low down richness gone and perfect fueling all the way to the red line, the engines faster and safer. Quick look at the fuel table and you can see its adjustable for any rpm and throttle position and you can even edit the rpm and tps bins.

Volumetric efficiency table Igniton advance table

The ignition table is exactly the same with total adjustability, handy if you've gone too high on the compression, just knock a bit of advance off at peak torque (although you'd be better off sorting the compression)

This system can also run in closed loop mode, meaning it monitors the exhaust oxygen content and adjust automatically as required, so if something changed and you started running lean or your air filter got soaking wet and started running too rich it will adjust the fueling to what ever AF target you have set.


Jack Pierce on the prototype Fuel Injected 250 Raptor

"its fast as ****!"
(roughly translated from welsh, we don't actually know what he said!)

Jack in action


We are working on making the conversion available as a kit, but as its under constant development its a ride in ride out product at the moment.

For more info contact us


Mk1 Throttle Body