Im turning my 94 auto into a track focused build. Having a 10 point cage installed and fire supression as required by my local tracks. My interior isnt in the greatest condition so gutting and building a custom interior is the route im going. A close friend who welds cages and dashes for joe gibbs racing offered his services. The plan is to eventually get a holley ecu once i modify the engine and trans. Ive read the gauge cluster on late c4s wont work with a modern ecu. I dont want to build my "cockpit" around the stock dash to only have to rebuild a new dash when i upgrade the ecu. My question is will i be able to wire standard analog gauges and switches with the stock ecu? Id have the same 6 gauges as stock tach speed oil temp oil pressure water temp and volts. For switches id have a battery kill switch, power on, ignition button, electric water pump, fuel pump, and fans. I plan on leaving space for extra gauges and switches should i want them later on, but for now would i be able to wire up everything listed with the stock ecu? Thanks for the help

 

After installing a good modern aftermarket ECU I have removed all extra gauges.
I still have the stock digital dash (1984) but I feed tachometer and speedometer from the new ECU.

I control both engine and transmission (4L80E) from the ECU, and I try to measure everything.

Having a lot of gauges while racing is pretty useless. All you really need is a warning light that something is wrong.
I get warnings for engine temp, lean condition, overboost, oil pressure ( at different pressures depending on load and RPM ), line pressre in transmission, EGT. It is possible to create warnings / error codes for whatever you can imagine.
I have a digital display where I can put whatever values or "gauges". I also see errors/warnings on the display.
I can also connect the laptop and download logs to see what the situation was when the warning occured.

When I was on a test and tune event I got a transmission line pressure warning, but other than the warnign i did not notice anything strange. It was pulling hard and no noticeble slip.
Checking the logs I saw that line pressure dropped a bit from half way on first and came back to normal a bit in on second gear.
I already had a bit extra oil in the transmission, but added a litte more and that solved the problem.
Without the logs and warnings I would never have known that it needed more oil at launch. ( 1.54 sek 60 foot and 6.34 sek on the 1/8 mile )

 

For individual instruments, Holley also has some really nice ones that work off of the CAN-BUS function of the Holley ECU. And matching standard type gauges available (for example a second AFR with the Holley HP as it only monitors one bank)… fuel pressure, oil temp and pressure, coolant temp, crankcase pressure, I think there’s a speedometer and tach maybe also, haven’t used that.

 

 

Eliminating the factory dash and any internal skeleton helps with getting the cage positioned in a much more friendly location.

Running the factory ECM with my own custom harness and fuse panel.

 

big fan of this build man looks great. So did you have any major issues working the stock ecu with aftermarket gauges? You said a custom fuse box will i have to modify my box as well?

 

You can run the factory fuse box, but it is attached to the dash skeleton. So you will need to figure out another way to mount it.

ECM does its own thing as long as it is getting the signals that it needs. Gauges are run directly with their own sensors. Oil pressure, coolant temp, oil temp. Speedo is GPS, tach is feed from the ignition feed.

 

With the Holley ecu their dash is plug and play and saves a lot of time tho is a little pricey.

Stock ecu can run some gauges and put others on their own circuit. Fuse box works zip tied back.

Nice build above ChumpVette.




Stock dash then aftermarket, this is after the great wire beautification project.