The Rooster

Anyone have any experince with these... I was flipping through the old parts book and Saw this mopar upgraded computer... anyone have one in there Renix 4.0? I was thinking of looking for one...

cruiser54

I looked a few years back and couldn't find one. I've installed a few Mopar Performance PCMs over the years. The advance curve is more aggressive and they recommend running unleaded premium as a result. If you want to advance your timing you can modify your CPS. You used to be able to buy "high altitude" CPSs but they're no longer available. I scored 2 of them when they were.
Cruiser’s Renix CPS Advance Mod
The sensor portion of the CPS needs to slide up the perforated bar towards the top of the engine.
Mark the perforated bar's top end with paint or marker.
Place the CPS in a vice, just not quite clamping the bar, the sensor resting on the vice jaws, with the Top part protruding.
Place a bolt that fits tightly into the hole at the Top part of the bar.
With a hammer, tap the Top part of the bar and it will slide through the sensor portion of the CPS. Stop when the sensor portion is about 3/8" from the edge of the bolt hole

The Rooster

Cool hm.. i might try that mod.... idk if I have the skill to do that mod...
but I did find the computer...
http://www.ebay.com.au/itm/GENUINE-M...-/251104405305

F1Addict

Oooo. Fun. I've got a Duralast CPS laying around on my work bench somewhere, I'm gonna try this.

cruiser54

I've done at least 10 of them with good results.

alsxj

how much more did you gain from the performance renix computers?

cruiser54

Not much. Pretty much a more aggressive ignition advance curve requiring premium gas. They have to be emissions legal.

The stock ECU from the 89 and 90, ending in part number 428 are the most desireable ECUs.

DFlintstone

I might mention here that the knock sensor is a nifty Renix feature. It's my understanding that the ECU advances timing continuously, then the knock sensor sets it back when it knocks. I'm unclear on what is gained with an advanced CPS at this time. My 90 normally does not "feel" retarded. (yea, there is a feel, doggen!) (mine don't do that)

ANYTHING I worked on with points got the max permissible advance, with a road test at temperature with the gas that was being run. "timing lights", are just a convenience for a shop that doesn't have the time to do it right. Yes, you can look at advance curves with one, but a real road test is how to find the optimum timing for a particular engine.

Cars of old had ign timing on the wheel/dash. Also it's more easily done in a van with the engine right there.

cruiser54

I don't believe that Renix advanced the timing until it "heard" knock via the knock sensor. Advance the CPS you chicken.

The Rooster

ohh that sounds like a challenge has been made....
Will he do it or will he not

cruiser54

I said "chicken" so you thought I was addressing you? LOL. He won't do it.....

The Rooster

ohh noo lol not me... i know you ment him I was just egging him on to see what would happen

cruiser54

You're not too chicken to do it, are you?

The Rooster

no i just need this modfied CPS I would do it in a heart beat
im not that handy with power tools

cruiser54

Take photos.