[urq] Re: ref sensors/signal timeing [was] First of many urq questions..]

[Steve Eiche]

Ben,
You are thinking of the flywheel speed sensor that reads the flywheel 
teeth.  This is on the top of the bell housing on the WX.  It really 
doesn't matter where this sensor is placed, as the flywheel teeth are 
evenly spaced with no gaps.  The timing reference sensor is located in 
the same place on the WX as later cars.

Steve

Ben Swann wrote:

> Steve E. ,
>  
> Although this is thekind of answer I was grasping for while trying to 
> answer, I question how this can be if the flywheels are changed.  The 
> earlier WX had the reference sensor located at the top of the bell 
> housing  lets say around 70 deg before TDC, and therefore I would 
> expect  the flywheel would have the pin located 10 deg after TDC on 
> the flywheel to get 60 deg.
>  
> The MC is located lets say for argument 10 deg after TDC and therefore 
> the pin would need to be located 72 deg before TDC.
>  
> The number I'm using are to make the math easier, but mainly that the 
> flywheel pin locations have to be different on the two engines in 
> order to come up with nearly the same ref. signal 60 vs. 62, as the 
> actual sensors are located in way differnt locations, one being before 
> TDC - almost behind the head, and the other being after TDC closer to 
> the oil pan.
>  
> Correct me if I'm wrong here, as I may be missing something, but i 
> don't think you can swap flywheels on the engines unless swapping the 
> location of the reference sensor, to come up with nearly the same 
> signal (different only by 2 deg.)
>  
> When I pull the WX out of my '83 I'll be able to compare flywheels, 
> but that won't be for a while.
>  
> Ben
>  
> [From: Steve Eiche [mailto:seiche at shadetreesoftware.com]
> Sent: Tuesday, April 06, 2004 4:21 PM
> To: Steven.Buchholz at kla-tencor.com 
> <mailto:Steven.Buchholz at kla-tencor.com>; 'urq at audifans.com' 
> <mailto:%27urq at audifans.com%27>
> Subject: RE: [urq] First of many urq questions (food for thought..)
>
> Steve,
>
> Yes, WX flywheel has the timing pin at 60 degrees BTDC.  The later 
> cars (MC, 3B, AAN, ABY, etc.) all have the timing pin at 62 degrees 
> BTDC.  The only effect of using a late flywheel with WX/WR electronics 
> would be that the timing would be advanced by 2 degrees.
>
> Steve
>
> ... I don't have the references here to back me up, but it has always been
> my understanding that the WX and MC engines differ in the location of the
> "reference" signal as measured to the actual TDC of the crankshaft ...
>
> Steve B
> San José, Kaleefohnia (USA)]