View Full Version : Can I use factory guages with the conversion?

04-15-2010, 03:10 PM
I am installing a 5.3 with a carb. Can I use my stock guages and wiring. I have the harness that was originally with the 5.3. Do I just splice my wires to the 5.3 factory connectors and use the 5.3 sensors?

04-15-2010, 03:17 PM
What kind of car are you putting this into?

04-15-2010, 04:06 PM
1987 Monte Carlo SS

04-15-2010, 04:06 PM
I'm going to guess a 2000 Z28.

04-15-2010, 06:09 PM
Well alot of info is sent through a serial data wire. You can get the tach, temp, oil pressure, speedo, and fuel gauges to work with some adapters.

04-16-2010, 10:34 AM
yes your gauges should work with the swap. If your speedo is cable driven then you need a converter box to convert the VSS into a cable wire.

04-16-2010, 11:47 PM
I have the Edelbrock intake with the MSD controller. I had the factory 200r4 transmission built with a stage 1 performance kit and a 2500 stall converter. Everything with that will just hood back up. My concern is the oil, temp, volt and tach.

I know the MSD box has a tach input so I have that covered.

I am also trying to figure out on my 2 pin alternator plug what pin goes to what. I started a thread about the Alt plug. What pin operates the guage and what is the other pin for?

04-17-2010, 12:02 AM
Find a diagram for your year monte and see if the wires even drive the gauge. Most GM alts of the time do not have a direct connection to the gauge. The gauge hooks into the dash 12v side and measures voltage across the entire system, not just alt output

LSx alts are computer controlled, so the standard gauge above doesnt have to be connected to the new alt at all to run

Use a 98 temp sender to combine the CTS and coolant sender into one piece that fits the LSx heads

Most GM oil pressure gauges have a one wire sender. Simply clip the 87 connector off and attach the 5.3 connector with the 5.3 sender

Tach is driven from your carb box

Speedo is driven by a cable box such as cable-x

04-17-2010, 12:05 AM
volt gauge will work fine with no additional wiring. You will have to swap the MCSS oil pressure sending unit into the LS1, use a metric to american adapter and it will be a bolt on.

For the temp gauge you will have to cut the MCSS sender down and rethread it. You can rethread it 12x1.50 mm and screw it right into the head where the LS1 sender used to go.

04-17-2010, 12:22 AM
My stock Alt plug has a brown wire and a red wire. The brown wire appears to go to the guage and the red wire is about 3" long and hooks to the battery post on the back of the Alt with the battery wire.

Pocket...Just to make sure I understand. I just need to use a temp sensor from a 98.

04-17-2010, 09:21 AM
Right, you can ignore the CTS function as you're carbed and only use the temp sender wire

There is no reason not to use the LSx oil sender either unless you just dont have it

Cutting the G-body senders down and using adapters to make them fit the LSx will work, but be aware that the LSx stuff will also drive your gauges

Look at your alt connector to see if it actually runs the gauges

Heavy red at pin S is a constant battery input

Brown to pin F is fused 12v IGN input to turn the alt on

Pin L would be your dummy light if you had one