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Discussion Starter #1
I am about to purchase a 91 jetta 8v w/ digifant. I was wonder what do you think of the injection system. I was also toying with the idea of converting it to a cis-e system. So I was wondering which yields the greastest horsepower and drivability. I have a 85 gti to get the cis-e system off of. Thanks
 

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digi 2 is easy. I think it's better then cis-e, but as far as horsepower goes not sure what the numbers are. You can't really use digi2 for forced induction, but if you switch to digi 1 you can. good luck
 

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how do you swap it injectors and comp?? i was think to try to get jettronic
 

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i was asking this question becuase I read that the cis-e was better than the digifant performance wise and forbest performance you should swap your digi for a cis-e.
 

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i read to swap it you will need a the entire intake system from the air filter housing to the intake manifold. The intake manifold and throttle body will need to swapped with one from a cis-e 8v car. The fuel pump, fuel lines, injectors, and fuel pump realy to the type of system that you are converting to. You also need to swap the distributor, coil, and ignition module. If you swap to a cis-e you will also need knock senor and tps.
 

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<BLOCKQUOTE><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><HR>Originally posted by MKIIgti:
i read to swap it you will need a the entire intake system from the air filter housing to the intake manifold. The intake manifold and throttle body will need to swapped with one from a cis-e 8v car. The fuel pump, fuel lines, injectors, and fuel pump realy to the type of system that you are converting to. You also need to swap the distributor, coil, and ignition module. If you swap to a cis-e you will also need knock senor and tps.<HR></BLOCKQUOTE>

CIS-E has more power potential that digi-2. There are more tricks you can play to get fuel from the system, and make more power. We've gotten CIS-E to fuel about 390ccs per injector so far (about 250hp worth of fuel on a turbo motor), while digifant-2 includes, and is pretty much limited to 200cc injectors (less than 120hp on a turbo motor).

Digifant came along for economy and drivability reasons, where as the performance cars from 86.5-89 (16vs) still used CIS-E and from 90-92 they used CIS-Motronic.

Really, if performance is you goal, switching to CIS-E probably is a good idea. Now that that's over with...

You will need:
Intake
throttle body switches
injector cups
injectors and lines
fuel distributor
airbox
fuel lines
fuel pumps (main pump is on a rack with the filter and accumulator, you need all of this)
complete engine wiring harness (preferably with the knock system from a 85-87 gti)
Ignition Distributor
Ignition Module
Intake tube and boots
front coolent neck w/ sensors
probably the coil
both the ECU and ignition box (if using knock system)
ISV and hoses
O2 Sensor

There might be a couple other stupid things I'm forgeting about, but you get the idea. Having a donor car to strip everything from is best.

The '91 would be CE2, so the wiring is different. It wont just plug in, but fear not. CIS-E is pretty simple, and once you've gotten everything you don't need out of the harness there's only 3 wire colors that don't seem to hook to anything. One is ground, one is switched 12v, and one is tach signal. The donor car determines the wire colors. Everything else should have a proper plug.

On a final note, try to source your parts from a running car is possible. Knowing the system worked before will really help sort out bugs when you try to make it run.
 
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