I recently got a 8 cylinder tach out of a junkyard for my car, because I had the original 6 cylinder tach in there and it was reading off becasue of the 350 that's now in the car. However it still seems to read about the same. The other day, according to my tach, I my engine up to about 8,000 rpms in first gear when I was driving the car real hard. Well, I know that's not right, because I've never seen a 350 actually wind out that high (this is just basically a street perforamnce 350) and second of all, there's no sign of the engine being over revved. (bent pushrods, etc.)

What could the problem be? I really doubt my tach is reading correctly, otherwise I'd be heving some serious engine problem right about now. Is it possible that I got another 6 cylinder tach? I don't think so, because the redlines and yellow lines and stuff are different. Is there something else I need to change?

-Thanks, Brandon

 

That's most likely, as most V6 tachs had a 6k redline.
That, or the tach you picked is bad.

 

Well the Tach works, I just think it reads high. It's redline is 5500 and the yellow is 5000. My 6 cylinder tach was 600 redline with 5500 yellow. I'm pretty sure it's not a 6 cylinder tach, but I don't know why it's reading off.

 

bump

 

Anyone know what the problem could be?

 

Have you tried hooking a scan tool up to the ALDL and checking the tac reading there? Or maybe hooking a engine analyzer up to the tach connection in the engine compartment?

 

There's no computer in the car, so I can't hook up a scan tool or anything. Where could I get one of these engine analyzers? I just hook it into the distributor cap where the tach plugs into?

 

Sears sells them as well as some auto parts stores.