Renix Cluster and Engine Swap Questions

[neohic]

I have my next hypothetical build happening in my head right now. Here's what I'm thinking right now for a recipe: GM 5.3 LS, 4L60 trans, and a GM/Jeep 231 bastard t-case. I know there are tons of warnings about cooling a V8 in a XJ/MJ and I know that there are plenty of reasons to keep a Jeep engine in a Jeep... that's not what we're talking about right now. :D What I'm thinking about is final details. Why not, right? Typically I need to think through and research every aspect and detail about a project before I even start. Tonight's topic is gauges.

 

RENIX clusters... There isn't anything between the senders and the gauge cluster besides the wire themselves, correct? If I were to use factory sending units (on the already said 5.3), run new wires to their appropriate gauge (assuming that everything as far as wiring under the hood would be a clean slate), then everything should function as it should... yes? The odd balls would be the speedometer, the fuel gauge, and the tachometer. I think the speedometer would be fine being I'd be using the back half of a Jeep 231 so I'd be able to retain the stock speedometer gear housing. The fuel gauge would be remedied by using a stock fuel tank (or build one that uses a stock fuel sending unit) so that I could use the stock gauge sender in the tank, delete the in-tank pump, and use a 5.3 compatible inline pump... or compatible in-tank pump. The tachometer has me stumped. :hmm: I know that the early RENIX clusters have the adjustable potentiometer that would make up the difference in signal pulses between the 2.5 and the 4.0s, but would there be enough adjustability for an eight cylinder engine? Now, many newer gauge clusters use a single pulse signal so they can read off of a single coil pack, but I doubt that I'd be lucky enough to use cylinder number one coil pack as a signal for a stock RENIX tachometer to read correctly. Push comes to shove, I'd probably use a cluster with the giant fuel gauge in place of the tachometer and substitute an aftermarket gauge mounted elsewhere. I'd prefer not to, though.

 

Right now, everything is just hypothetical. That's not to say that I'm not planning a new build for a wheeling rig at some point... stay tuned for that. Let's get the conversation going, shall we? Keep in mind that I do not want to use aftermarket gauges for anything. I want a stock looking dash. Here's a picture I found of a couple clusters... 'cause people love pics. :laughin:

 

[FrankTheDog]

I think you add your renix oil pressure and water temp sending units to the engine along with the sensors that the 5.3 needs for it's computer.

[tugalo]

If the original Renix senders will not physically fit into your new engine, you might run into a problem with the OEM sending units on the new engine having a different ohmic value than the old Renix senders.  That may throw your gauges off a bit, 

 

You will almost certainly have to change out the connectors to the senders, but removing and replacing pins in connectors is no big deal.

[neohic]

All of the original senders for the new engine would need to be retained to function properly. I was thinking more of using then along with adding the RENIX senders for the original cluster. So... my main question was about what's between the senders and the gauges themselves.

 

What about the tachometer? Is it possible to figure a way to use the stock RENIX cluster tachometer in an eight cylinder application?

[Eagle]

I know that the early RENIX clusters have the adjustable potentiometer that would make up the difference in signal pulses between the 2.5 and the 4.0s, but would there be enough adjustability for an eight cylinder engine?

 

 

Correction -- the LATE Renix tachs had the adjustable potentiometer. The early Renix tachs were 4-cyl or 6-cyl specific, without the adjustable pot.. A friend of mine swapped a later tach into an '84 XJ 4-cylinder. He reported that calibration was easy -- all the way in one direction for 6-cylinder and all the way the other direction for 4-cylinder. If he's correct, then it can't be adjusted for an 8-cylinder.

[neohic]

The factory tachometer signal can get tapped off of the coil for an aftermarket gauge but it'd be the same wire that goes to the factory tach in the cluster. If a signal converter would be used, one would be able to retain a full factory cluster, right? Does the factory tach run off of a six pulse signal?

[A-man930]

Looking at the schematic for my '90 it looks like the oil pressure and coolant senders are directly hooked to the cluster.  

[Rockfrog]

They are, all the guages are autonomous of the ecm if that's what you are wondering.

 

Sent from my SGH-I337M using Tapatalk

[neohic]

Any thoughts on having a functioning factory tach?

[Eagle]

Any thoughts on having a functioning factory tach?

 

Custom dial decal?

[A-man930]

 

 

Any thoughts on having a functioning factory tach?

Custom dial decal?

I've wondered if this was possible too...

[neohic]

So... the tach?  :dunno:

[DirtyComanche]

On the tach I'd see what the resistance range is on the adjusting potentiometer.  You might be able to swap it for a different one to produce an output range that will work.  Then just calibrate the tach vs a timing light or whatever the ECM is reading.

 

Or this: http://www.dakotadigital.com/index.cfm/page/ptype=product/product_id=127/category_id=287/home_id=59/mode=prod/prd127.htm

 

Or you can probably use the tach output from the ECM and change the output via EFILive or something like that (I don't know, up to you to research that).

 

For your fuel gauge you might be pleasantly surprised to find the GM resistance range is the same as the Renix.  The Renix range (0-99 ohms) is the 'standard' GM range, as they were using GM parts.  I don't know if they went away from that standard on later stuff or not though...  Should be easy enough to find out.

[Eagle]

For your fuel gauge you might be pleasantly surprised to find the GM resistance range is the same as the Renix.  The Renix range (0-99 ohms) is the 'standard' GM range, as they were using GM parts.  I don't know if they went away from that standard on later stuff or not though...  Should be easy enough to find out.

 

I thought the Renix fuel gauge sender was 0 to 88 ohms. That's what my '88 factory Electrical Troubleshooting manual says.

[DirtyComanche]

 

 

For your fuel gauge you might be pleasantly surprised to find the GM resistance range is the same as the Renix.  The Renix range (0-99 ohms) is the 'standard' GM range, as they were using GM parts.  I don't know if they went away from that standard on later stuff or not though...  Should be easy enough to find out.

 

I thought the Renix fuel gauge sender was 0 to 88 ohms. That's what my '88 factory Electrical Troubleshooting manual says.

 

 

Yeah, I was thinking of something else that uses GM parts.  They are 0-88, but it should work fine, a guy might have to pull the needle off and realign it a bit to ensure that it has an even sweep from full to low...