88 GTU (S4 N/A Manual)

Before I fiddled with my oil pressure gauge mechanism, my 2nd gear would hit 60mph at about 7k-ish rpm. Now it barely touches 6k rpm at the same speed. I can tell by ear it's spinning just as fast, but the tach reads differently.


The short simple question is:

How fast should my engine be turning at 60mph in 2nd gear?

 

Lot of variables in play here...for instance, what size rear tires?

 

the tach is off up top, but it shouldn't have changed....

 

I'm not positive it is. However the sound of the engine in relation to speed, is very close to the same. You know the sound of 7k rpm in your car, you know what I mean? The engine sounds like it used to, per mph, but the tach is reading differently.

I suppose I can have someone pace me.

Tires are 205/60/15

FWIW for the calculating guys, the 88 GTU has a 4.10 LSD rear end.

That's the thing, it did.

I removed my cluster to repair those two gauges (oil pressure/voltage). Didn't touch the tach or speedo at all. Put everything back in correctly, now the tach is off. I say the tach, because the engine has the same sound per mph as it did before, but the tach is reading way low.

 

double post

 

I found this:

http://i114.photobucket.com/albums/n...cture453-2.jpg

Those numbers correspond to what it read before, but not what it reads now.

Like I said, the engine sounds the same as it did, but now the tach reads low. Lunch in 15 mins, coworker is gonna pace me, 50mph in 3rd gear.

 

While you're at it, do a couple different speeds to figure out if it's a scaling issue or an offset issue.

 

wtf ... now it reads correctly. We paced at 20, 30, 40, 50, 70, 80 ... Everything matched the picture I linked with a single "issue" ... My speedo reads ~3mph high consistently.

But now that my tach is working correctly, my idle went to **** again...******* a.

I swear this damn car is possessed.