78 WUR on 77

[unclebilly]

I bought a new WUR on ebay last week. It arrived yesterday and is for a 78-79 car. Will this work properly on my 77?

The seller ensured me this was correct for my car but the part number on the box matches the part number for a 78-79 on the Pelican Parts Site.

If it won't work for my car I'd be happy to sell it here for what it cost me.

[boyt911sc]

Uncle,

What's the number on the housing (0-438-140-xxx)? A '76-'77 WUR is designated as 0-438-140-033. What number do you have on your old WUR?

TD

[unclebilly]

Yah, this is -045, not 033. My car has the 033 on it.

[Paulporsche]

Even though the WURs and their curves are different, they are similar, and there is a lot of overlap. Depending on the ambient temps in place when you use your car, you may find it works just fine. I have a WUR from an Audi 5000 on my modded SC engine that works just fine most of the time. One day, when I get around to it, I'll finally check the control pressures so I can set it more exactly, but for the last 2 years or so I've been using a "mismatched" onw with good results.

[Paulporsche]

Even though the WURs and their curves are different, they are similar, and there is a lot of overlap. Depending on the ambient temps in place when you use your car, you may find it works just fine. I have a WUR from an Audi 5000 on my modded SC engine that works just fine most of the time. One day, when I get around to it, I'll finally check the control pressures so I can set it more exactly, but for the last 2 years or so I've been using a "mismatched" one with good results.

[T77911S]

once the WUR reaches operating temp, do they work the same from then on?

[Paulporsche]

Yes, but you can see from the graphs that the control pressures will be slightly different depending upon the WUR. This however can be compensated for somewhat by the mixture setting.