FI retrofit, it's done!!! |
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FI retrofit, it's done!!! |
toon1 |
May 17 2007, 07:31 PM
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#1
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Senior Member Group: Members Posts: 1,849 Joined: 29-October 05 From: tracy,ca Member No.: 5,022 |
I've been working on retrofitting newer fuel injectors for the 914. My goal was to find an injector that can utilize as many of the stock parts as possible.
I came up with a inj. off a 96 forn escort 1.8l motor. One comment is needed, this will only work with an aftermarket FI system s these inj. are HIGH inpedence. This setup gives the ability to use higher fuel pressure, 44psi . It has a lower flow rate than the stock inj.. so the pulse widths will be longer and should give a little better idle quality. these are disc style rather than pintle( stock). fuel atomization will be much better giving a cleaner, more efficiant burn. The length of the inj. where shorter than stock so I added an O ring to make up the difference. The plastic tips are different ,I cut them off and put the tip of the stock inj. on the new inj., fit perfect. now the stock tip O ring can be used. the fuel rail was machined to tolerance for the top O ring seal. And I made a bracket to support the fuel rail from vibration and also keeping it from popping off the top of the inj. Here's the setup assembled. enjoy Attached image(s) |
toon1 |
Nov 24 2007, 12:35 AM
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#2
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Senior Member Group: Members Posts: 1,849 Joined: 29-October 05 From: tracy,ca Member No.: 5,022 |
I did some calculations with the ford escort inj. and determined they were a bit too small.
After running the calcs., I did some work with MS on stim and With the flow rates of that inj., the duty cycle at WOT. was about 115%. The FP would have had to been run at about 55psi to get the flow rate for 85% at WOT. I had a set of four inj. from a ford probe INP480's. The flow rate was hard to find but it flowed about 21lbs/hr, about the same as the stock inj. but at 43psi. After running those #'s on MS and the stim, it looked good. I had pw's at idle around 2.2ms. these will also give the latatude to lower the FP, if needed and not hurt the fuel atomization. The probe inj's had a smaller top so I made some new rails with smaller holes. otherwise everything else fit the same as the escort inj's. The connectors where no prob., I just cut them off the wire harness of the probe. they fit just fine with the inj's. in the rails. I have not put them on the wire harness yet but will soon. with the inj's. on the air intake runners which are installed on the motor, it all looks good (IMG:style_emoticons/default/biggrin.gif) I am also retrofitting an EDIS system to the motor,direct coil drive so I have to add a 2nd coil driver. The engine parts took forever to get back from the machinest(4months!). Right now the engine is built and close to being ready for install. Unfortunatly I have run into probs. with my truck. The tranny had to be replaced and also the intake man. gaskets so it has be occupiing my time for the past few day's The car is still a way's off from running but I am anxious to get it going. Keith |
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