Technical => Engine Tech => Topic started by: Carl on July 07, 2006, 12:03:14 AM
Title: Bigger Injectors For CFI?
Post by: Carl on July 07, 2006, 12:03:14 AM
I have heard ford made 42lb injectors that you can put on a CFI system. Is this true? Are there bigger injectors that I can put on my cfi?
I already have some of the parts needed for the carb tranfer including a holley 650 4bbl carb. >8)
Title: Bigger Injectors For CFI?
Post by: Ifixyawata on July 07, 2006, 12:06:08 AM
I'm not sure it would help too much considering the bore size of the throttle body is still the same size. It seems like it would just make the fuel mixture richer, cause black smoke. You can however try and find the "H.O." CFI that came on one year of Mustang and I think the LTD LX or Midsize LTD police cars. I think it has a larger bore and bigger injectors.
Title: Bigger Injectors For CFI?
Post by: Carl on July 07, 2006, 12:28:12 AM
Oh well haha.
Looks like I will just be getting the other parts for the carb conversion.
Title: Bigger Injectors For CFI?
Post by: Thunder Chicken on July 07, 2006, 12:40:27 AM
Scott (jcassity) experimented with larger injectors in a CFI - I think it was unsuccessful.
Title: Bigger Injectors For CFI?
Post by: jcassity on July 07, 2006, 10:48:23 AM
Quote from: Thunder Chicken
Scott (jcassity) experimented with larger injectors in a CFI - I think it was unsuccessful.
first off,,,,,, I did find a 5.0 CFI and the butterfly and bores are much larger than the v6 CFI. All the pre sefi V8's had this CFI. However,, there is a third CFI out there and i have yet to secure one. I did see it but it was going out the door when i was walking in the JY office. Just find a 5.0 CFi in any configuration,, there are two configurations out there so you just adapt it to your desire. You will know what i mean when you see one,, hard to explain. 84 Fila has the odd / older configuration im talking about. He has a couple pics on one of his threads. That would be the exact one i ended up with. This CFI was Fords transition from the EEC controlled Carb to eec controlled CFI. Some externals of the carb/cfi remained and you will need to delete these.
Now,,,,,,,second If you simply take your existing CFI and remove the butterlies and tps, slide out the linkage, you can use a baby cylinder hone to make the bore ports match up to your intake and egr plate. The intake and egr are larger than your CFI bore (for some odd reason:mad: ). Trust me,, the bores on the bottom of the CFI will bore WWWWAAAAAYYYYY bigger,, lots of meat there. Next up will be to locate and old carb and decide which butterflies you wanna put on.
Third....... I did install a 5.0 cfi (no additional bore but what was stock) and swap in blue top injectors. It ran too rich for my V6. If you simply find the 5.0 cfi (easy to find) and put in your green tops,, you will notice an ***Very nice**** gain in response. All you have done is increased air at this point. If you bore out the bottom half of the CFI and go with larger butterflies it will help even more but at some point your valves/cam are not responding to this benefit due to size/duration time. Finding butterlies should not be hard since you tinker with carbs anyway.
In a nutshell,, find a 5.0CFI and remove/install your green tops Dont re-install the injector lower retainer,,, ( have a trick for that and its worked for several years now) This helps when you wanna just remove injectors and requires no tools. remove the stock freeze plug from the top of your FPR with a drill adjust your fuel presure up a half to full turn Clockwise with an allen wrench non stock FPR's have a plastic plug and no adjustment (from what i can see) while you have your injectors out , locate a wood/self tap screw start the screw in the top of the injector gently give the screw a hard yank with pliers out will pop the little tiny tear drop screen. most of the time they are collapsed or black removing the screens deleted my age old prob of hesitaton if you feel froggy, install a second inline filter at the fuel feed, i did.
Title: Bigger Injectors For CFI?
Post by: 84 Fila on July 07, 2006, 11:12:57 AM
Should I be listing to this or go back to my corner and wire some more?
Title: Bigger Injectors For CFI?
Post by: V8Demon on July 07, 2006, 01:28:21 PM
Quote
Should I be listing to this or go back to my corner and wire some more?
I have no idea what you mean, but Jcassity knows his stuff.
Title: Bigger Injectors For CFI?
Post by: TurboCoupe50 on July 07, 2006, 02:11:25 PM
As Scott found out, more fuel does you ZERO good without increasing air flow...
Title: Bigger Injectors For CFI?
Post by: Carl on July 07, 2006, 07:51:31 PM
Quote from: jcassity
first off,,,,,, I did find a 5.0 CFI and the butterfly and bores are much larger than the v6 CFI. All the pre sefi V8's had this CFI. However,, there is a third CFI out there and i have yet to secure one. I did see it but it was going out the door when i was walking in the JY office. Just find a 5.0 CFi in any configuration,, there are two configurations out there so you just adapt it to your desire. You will know what i mean when you see one,, hard to explain. 84 Fila has the odd / older configuration im talking about. He has a couple pics on one of his threads. That would be the exact one i ended up with. This CFI was Fords transition from the EEC controlled Carb to eec controlled CFI. Some externals of the carb/cfi remained and you will need to delete these.
Now,,,,,,,second If you simply take your existing CFI and remove the butterlies and tps, slide out the linkage, you can use a baby cylinder hone to make the bore ports match up to your intake and egr plate. The intake and egr are larger than your CFI bore (for some odd reason:mad: ). Trust me,, the bores on the bottom of the CFI will bore WWWWAAAAAYYYYY bigger,, lots of meat there. Next up will be to locate and old carb and decide which butterflies you wanna put on.
Third....... I did install a 5.0 cfi (no additional bore but what was stock) and swap in blue top injectors. It ran too rich for my V6. If you simply find the 5.0 cfi (easy to find) and put in your green tops,, you will notice an ***Very nice**** gain in response. All you have done is increased air at this point. If you bore out the bottom half of the CFI and go with larger butterflies it will help even more but at some point your valves/cam are not responding to this benefit due to size/duration time. Finding butterlies should not be hard since you tinker with carbs anyway.
In a nutshell,, find a 5.0CFI and remove/install your green tops Dont re-install the injector lower retainer,,, ( have a trick for that and its worked for several years now) This helps when you wanna just remove injectors and requires no tools. remove the stock freeze plug from the top of your FPR with a drill adjust your fuel presure up a half to full turn Clockwise with an allen wrench non stock FPR's have a plastic plug and no adjustment (from what i can see) while you have your injectors out , locate a wood/self tap screw start the screw in the top of the injector gently give the screw a hard yank with pliers out will pop the little tiny tear drop screen. most of the time they are collapsed or black removing the screens deleted my age old prob of hesitaton if you feel froggy, install a second inline filter at the fuel feed, i did.
I already have a 5.0 CFI. :D
Title: Bigger Injectors For CFI?
Post by: V8Demon on July 08, 2006, 11:12:03 AM
Yes, but as mentioned it is possible to bore out the housing a little for more air flow if you wish to stay CFI.