All right guys. I need to know what problems I would have swapping a v6 cluster in to my v8 car. I know the oil pressure gauge is the first to jump out but I have an aftermarket oil pressure gauge. Anything else that might cause a problem?

 

I swaped a v6 for a v8 awhile back on my 89 camaro, all v6 gauges worked with the v8 except for the temp. even the tac seems right, it amazed me.
2.8 v6 to 305tbi swap cost me $75.00 and the 2.8 was dead

 

If the clusters are from the same year - the V6 Tachometer will NOT be accurate when reading a V8 distributor. You would need to swap your original Tach in the replacement cluster. ( this resolves the oil pressure readings as well )

The cluster design changed in 85. If your car is an 84 than be sure the cluster you are installing in it is also from an 82-84 or there will be other issues to deal with. ( Backlighting and Brake warning Light ) If you have an 85-89 replacement cluster than you could simply reuse your original cluster and simply install all the 85-89 gauges ( except V8 tach ) into it and everything will be OK.

 

Alright thanks. But I lucked out and got a cluster off of e-bay that came out of another 84 LG4 car. It is suppose to be in great shape, I guess that remains to be seen tho. Now when I replace my old cluster with this other one if the tach is still all screwed up where should I go from there?

 

If the tachometer in the replacement 84 cluster isn't accrate it's going to need to be replaced. If your car is a V8 and the tach is a V8 tach ( Identified by the 30-60 Oil pressure gauge ) than it SHOULD work as intended.

If it needs to be replaced than you can use a tachometer from ANY 82-89 V8 Camaro in it's place. ( The "face" changed in 85 - but it's still plug and play into any gauge cluster. ) The L69, 85 TPI, and 350ci clusters yellow line @ 5000 compared to 4400 for all other Carb and TBI V8 tachometers. )

 

I also have a similar problem. i replaced a V6 with a V8. My water temp, oil, and tach do not work. Just to clarify this i would have to get a tach from a V8 correct? what should i check about the water temp gauge?

 

If you swapped motors from a V6 to a V8,..... Yes, you will need a V8 Tach in order to get a correct reading. ( There are also aftermarket converters available for about $80 on the web - but that's another story ! )

Can't really say why your gauges and tach aren't working. Could be related to the engine swap or the sensors might not be connected. It is possible to have more then 1 guage fail at a time - but not probable. A failed printed circuit could also be the cause.

The coolant temp gauge is running off a sensor in the drivers side head. This sensor should have a dark green wire leading to it. Clean the end of the sensor with a wire brush as well as the terminal at the end of the wire. Be sure it's re-connected and see if the guage works. If not; You can either probe the wiring to see if the sensor is working right - or buy a cheapo replacement and install it. If the gauge still doesn't work the problem is in the cluster, the guage, or somwhere along that green wire.

 

Thanks I appreciate the info

 

John,
I've heard about this backlighting problem before,but does that mean the gauges won't light up or what?
Wilhay

 

I don't have a picture of a 84 dash and an 86 cluster,... but I have a picture of an 86 dash with an 83 cluster. ( don't mind the 82 tach ! )



As you can see the BRAKE warning light will not work and the backlighting on the bottom left doesn't work when the park/headlights are on. IIRC that backlight does come on - but VERY dim - when the park/headlights are turned off.

 

Hey John,

I put another post cause I thought this one was dead. But the tach in the new cluster I got doesn't work either. The guy I bought it off of threw in another cluster for parts in the tach doesn't work in that one either. So now what should I do?

 

Sounds like your gonna' have to do some wire probing with a voltmeter to see where the fault is. Start at the distributor to be sure that it's sending a signal, than check that the tach filter is OK ( if your car uses one ) and work your way back to the cluster.

There should also be some type of a test to verify that the tach is working right. I don't know what it is, but I'm sure if you apply variable voltage and ground to the posts on the back of the tachs than the needles should move. Sorry; but I don't have any specific info for you like what one gets voltage or how much,........

 

So it is not likely I got a bad tach? The seller claimed it worked 8 years ago the last time he drove the car it was in. It does drop to zero when I turn on the key, but when the car starts it goes to 2200 and stays there till you give the car gas. Then it goes to zero till you let off. The tach from the other cluster was for a V6 plus the post were all rusty as was the rest of the cluster it's self. My old one worked fine up until a few weeks ago. So could it possibly be something in the distributor? Thanks for trying to help me.

 

It's VERY possible that your dealing with bad Tachometers. They are known to fail and since you have never witnesses either of the replacements working correctly - you really can't assume that they are in good working order with any certainty. They are - after all - 20 + year old electronics.

The simple fact that the tach moved at all when the car is running means that it IS getting a signal thru the clusters printed circuit. Knowing that - I would lean towards the tach as still being the problem.

 

I would see if someone has a tach you could borrow. There's also some hand held diagnostic equipment that has a tach function as well. You would be able to check the function at the distributor pick up and also where the cluster plugs in. Once you know the signal is good at the cluster you can also check the cluster itself, and then suspect the tachometer.

Another option is to remove the tack and wire it directly to the distributor pick up and ground using wire with alligator clips on the ends. (I would avoid touching the tach lead while it's running.) On the back the circuit board should be labeled coil and Gnd (Ground). The coil lead goes to the distributor. IIRC, there is no positive lead, I'm going off of memory though.

Even if/when yours is working, it's good to know how accurate the one you're running is.

 

I was thinking that was more than likely my luck. Cause the reported good one does work some what correctly. If I was running my car in the 3500 to 7000 rpm range. Cause that is where it functions at. But at least it tries to work. I don't know anyone to borrow one off of. But I will try wiring it at the distributor see what happens. Thanks for trying to help me out.