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Discussion Starter #1
Ok I’m getting ready to finish my first engine rebuild. It just so happens that it is a 7 bolt 4G64 (it has a crank angle sensor just like a 7 bolt 4G63) and it is going to have a 1G head. I was wondering if it would be at all possible to use the signal coming from the crank sensor to act like the CAS. Kind of like how the 1G CAS on a 6 bolt swap works as both the CAS and crank sensor. The reason I think that this should work is because a 93-94 CAS uses the hall-effect just like the 95-96 CAS and crank angle sensor. If you are wondering why I would like to do this it is because I do not want to buy all of the parts 97-99 CAS parts nor do I want to do the RRE weld build up method.
 

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see we are lucky with our 95-96 cars (sarcastic) you cant use just the crank angle sensor...you can try it but i dont think its going to work i do believe that the crank sends part of the signal needed for the ecu to determine when it should fire and or when it should open an injector. i have a 95 with 1g head intake throttlebody and trying to use the 1g cas doesnt work with our ecus because of the inverted signal i have tried both of rre's ways and niether work correctly. and good luck getting ahold of the service dept at road race too... but i have seen guys with 97 models get away with it for about twenty minutes worth of work with no problems because the 97 ecu reads the cas the way its supposed to be read.... im thinking about getting a 97 ecu and seeing what happens.... if you have any answers please let me know....and as far as the 1g cas goes are we (2g guys) supposed to use only the 94 cas or can we use from different years as well. i have two cas's both from 91 model year cars....
 

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Discussion Starter #3
Yeah I know that we have the special cars :mad: . Someone correct me if I'm wrong but I belive that you can use any 1G CAS however you get an occasional random misfire.

I wish I knew the first place to start to testing a 2G Crank Sensor to see if you could get it to work as both however I have no freaking clue. If I can't get it wired up my self then I'm just going to fork over the money RRE wants for the premade cable or see if there is a machine shop that can weld up some material so I can use the stock 95-96 CAS on the 1G head.
 

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you could probably just try to wire it up like rre's instructions and just use the crank angle sensor but what you might want to do is go to vfaq> engine> 1g cas in 2g> then go down to the bottom of the page and look for >"cas geek info" >click on that link scroll at the bottom of the page and it will show you the plate that is in the cas. it has six slots on it and two of them are for tdc and 180 out i think the others are for spark..... not really sure exactly how they work... on another note i rewired the 1g cas to go directly into the ecu instead of going through the stock wiring harness... it did clean up the signal but car still does not run right.....i had two leaking upper o-rings on number 2 and 3 injectors i fixed them but the car still does not run right... it is getting alot of fuel with the 255 fuel pump and my pos command joke regulator will not let me adjust fuel pressure down to what it needs to be i swicthed back to stock one...so i am going to swap stock fuel pump back into it just to see if that makes a difference i am also running stock injectors at the moment as well untill i can get the car to run right..... if noen of this makes a differnce i am going to try a 97 ecu if that doesnt correct things then i am going to revert back to 2g stuff just so the car runs right again...
 

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But will a crank sensor and a cam sensor be the same wave form? Saying you did wire in a crank sensor? I doubt it. The 1g CAS "simulates" crank angle from camshaft speed. I doubt a crank sensor; being of specific duration will have the same "logic" built in when using it backwards. Also, it only has one signal output wire. Good luck. :p

I have a 1995 Eagle Talon TSi.
I used long pigtail 90 CAS. Switched the harness plug on the car side of the CAS plug to the 4 wire 1g CAS plug. Then, I plugged it in. Put the car back together, and never looked back. No hiccups, No CEL, nada.
I did nothing else.
Oh, I switched the plug wires from coil to coil. That's it.

Maybe I'm missing something..? I read about the injector signal being inverted as well... or something like that, but it runs fine. Decent gas mileage... good power, instant response... don't know what to tell you. :confused:
I guess if all thats true my car is REALLY fucked up and I can't tell. Maybe its being sneaky... BAD DSM BAD! :mad:
 

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Discussion Starter #6
I'm probably just gona end up doing it the way you told me to do it before Asmodeus. However I am still going to investigate doing it this way simply for the fact of cleaning up the engine bay and making the head look more like a stock 2G head :) . . still all about the stealth :D
 

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Do it how you want to... I could be wrong.
Its just funny to me, as if noone told me all this stuff wouldn't work when I did it, and I'd have to stand on one foot, do backhandsprings while whistling star wars, in a swimming pool, full of jello and cement... I would have never noticed. It runs as smooth or smoother than my friends BONE stock 95 TSi Awd. I dunno. :confused:
Glad I'm not the only one that used my intake manifold as a gas can. I had to change out 2 injector O rings... I must have cut them when I put the inj in the rail. Didn't leak until 3 months later... I don't run real rich either. I do now, cause I'm leaking boost... But I was pretty clean before. (For a DSM. none are clean)
I think I'm running a 2g rail, with a 1g fpr... no clue, I picked one up out of the 5 put it on the rail, and bolted it on. :rolleyes: Of course, with my pile of parts, it could have been from a 2.4, 2.0n/t 1g 2g turbo... who knows...
*shrugs* I dunno... :)

Maybe I put the CAS on upside down and it reversed the bad mojo back on some engineer at plant Mitsu. One can only hope... :D
 

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well i did switch to a 1g head intake and throttlebody as well vso my car might react a bit differently... i put the 2g crank angle sensor back in and used the hex inverter on the cas and then started the car seemed a little better but it still does not run right if i hit the gas pedal a little it sounds better above 3k but still doesnt idle worth a shit sounds like its missing. and the car doesnt fire right up either ... funny i tested my coil packs they are fine plug wires are fine new plugs too... it is getting sufficient fuel as well but then again me having the 1g upper half might have something to do with everything.. im still trying to figure things out... i still think i am going to get a 97 ecu for it just to see..must be nice to have done the conversion with no headaches :D
 

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Discussion Starter #10
Re: Using 95-96 Crank Angle Sensor in place of the CAS

NJ_Talon_Tsi do you have any more pictures of the bracket or fabrication?
 
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