My tach seems to be very off or slow or whatever but it is really starting to concern me. I know our tachs are not very accurate to begin with but this is ridiculous. My red line is at like 6800 on the tach and my MEVI which is set at 5000rpm right now activates at like 5400-5500 according to the tach.

I was just wondering is there anything I can do to fix or correct that. Can a dealership correct it with a consult? Would a new gauge cluster fix it? I am getting a JWT ECU soon but IDK if that will help or fix it or just make it worse. I guess I can just shift at like 7500.

I don't think the MSD RPM switch for the MEVI had anything to do with it but I guess it could have. If anyone knows of anything it would make my shifting a little easier.

BTW I did search the best I could and didn't find anything really definitive.

 

The 5.5g are even worse. I notice my 95 is a bit closer than your 4g though, as it's only off by about 200rpm. As of right now, there are no fixes other than getting an aftermarket tach (ricey IMO)

 

It is probably not off that much. Using MEVI activation is not an accurate way to judge your tach being off.

 

How does getting an aftermarket tach fix that? Doesn't it use the same sensor? And does that fix the speedometer at the same time, basing the speedo on the RPM's, right?

Yes, that question is on the dumb@ss hall of fame, I know. Feel free not to remind me.

 

aftermarket tach are more accurate in their readings....

 

My tach at one point would not register anything under 1,000 RPMs. At idle it would just go down to 1,000. I just replaced the cluster and it works fine.

 

Aftermarket tachs are more accurate but it also depends on where your pulling the RPM signal from.

 

It was alot easier back in the day when you had a single coil

 

I believe your MSD RPM switch is whats not accurate. There have been many posts regarding the setting of that switch and the actual opening of the MEVI valves not corrisponding to actual engine RPMs.

Use a digital tach to verify your MSD settings and your factory tach. I guarantee a properly functioning factory tach is more accurate then you think.

 

Yeah if it was just that then I might not be too worried but my rev limiter being more and more into the red line on the tach also makes me suspicious. I need to get my hands on an ODB2 reader or something to accurately read my rpms.

 

My tach is 100% dead. But I tell you what, I'm awesome at listening to my engine and guessing within 200 RPMs now! Damn old cars! Aux tachs are the most cost effective methods of a remedy to this problem.