Hi,

I just purchased a 1990 Iroc Convertible and the tach reads way to high? There is no way that I am shifting a stock 305 at way past 7000RPMs.

Question: Did someone change the dash for a v-6 dash? I know the mileage is not correct. Would getting a v-8 dash correct this?


Another Question: Does anyone have any infomation on the Marlboro giveaway for the 1990 Iroc? This is a giveaway car and would like some information?

Thanks

Welcome to TGO.

The tach being off is a very common problem in our 3rd gen cars most likely the resistors are just bad and it is causing the tach to be off by a certain percentage. I'm not sure of what the resistance is supposed to be originally but try searching on tachs that are off, you'll get a lot with just people answering to search I'm sure, but somewhere I would bet that the answer is there.

As for the Marlboro-give-away try asking that question in the history forum and they should be able to give you some stats on it.

Beautiful car by the way.

A couple of years ago I switched out to a Monster Tach for my race car. I wrote it up on camaroZ28.com and here's the link.

http://www.camaroz28.com/forums/showthread.php?t=126671

Let me know if that link helps you out, remember that I have an 87, Your car might be set up differently.

Brian

Can this be fixed or do you need to replace the gauge cluster?

It can be fixed if you have a function generator and aren't afraid to solder parts.
Or I can do it for you. PM me if interested.

Lou