Alright so i have a 1994 Camaro Z28 Vert with the 2.73's and i have the 115 mph speedo. I want to get white faced guages for the car so im wondering if i can get the 155 mph guages, and have the computer tuned to read accuratly with the 155 guages. I know what some of you are going to say and thats "just get a 155 cluster" my answer to that is no. I have 33k mi, and i want my odo reading accurate. So is this possible? Thanks in advance

 

You could probably use a Dakota Digital SGI-5 interface box to alter the signal from the PCM. If you alter the PCM to read what is in fact an incorrect speed, it would affect any tables that rely on vehicle MPH.

http://www.dakotadigital.com/index.c...rod/prd126.htm

You could probably remove your odo mechanism from the original cluster, and transplant it to the new one.

 

Yes, it can be done. Enter your existing gear ratio and tire size in Tunercat and let it figure your constants. Go here and download my spreadsheet to get the numbers. Scale the speedo scalar by the ratio of 155/115. I figured this out by mistake when Datamaster read my speed correct and the speedo read way off.

http://www.impalassforum.com/vBullet...d.php?t=181573

 

The zip file cannot be downloaded unless you are a forum member at that site.

 

PM me with your email and I'll send it directly to you.
Anthony

 

didnt know z28s came with a 115mph speedo.. i thought that was just for v6s

 

It was dependent on the tire option.

 

I got the 115 speedo in my Z, its almsot a collectable for that reason hah, jk

 

Thanks everyone who replied. Especially aknovaman! I dont know what this "Tunercat" thing is exactly. Is this a software i can get for the car? Is it free or do i have to pay? I was going to send the comp into PCMforless but if i can get this done with a simple cable purchase than id rather do that for sure. Quicker and cheaper ya know?

 

Tunercat software is the program used by tuners to modify the file in your PCM. It's available ftom Tunercat.com for $69 plus $20 for a definition file for the OBD1 LT1.

The dash speedo is something I'd have to walk you through to get it dead on the $$. I use my GPS to get my speedo prefect for my customers.

BTW
I lived in Anchorage for 8 yrs from 1992-2000.
Miss the fishing, lots.

PM me if you need info.

Anthony