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Another R4 question

Twisted Steel Performance

Twisted Steel Performance

Anything worth doing is worth overdoing.
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I talked with my ac man today, my 93 dually needs a compressor at the least ( PS mounted)

He said NEW-not rebuilt R4's are readily available. He also said their are 6 piston versions as well as the standard 4 piston and I see vane style also. He didn't have the time to look in the delco book at the time for a part number.

Anyone have knowledge of this? A part number?

I don't really want to convert to another type compressor.

Plan is to replace compressor, dryer, condenser, switches..

The current system works well but the compressor is weak and the switch on the dryer sticks and freezes everything up once in a while..

Thanks
 
R4 pancakes is a 4 cyl period. The other options sound like a different compressors. Doubt they fit.

There is a higher CFM R4 for dual air suburban you could use.

Have you replaced or rebuilt the hose set yet? Make sure the high pressure kick out for R134a is used and wired to keep the diode on the clutch coil. The clutch diode is in the harness and I missed it wireing the high pressure cut out in. It arced the switch closed. A bad diode could arc the low pressure switch too.

My last 4 Seizeons (4seasons) for something else was a Commie China made unit. Not sure what brand to recommend now.
 
I looked at RA for the 88-95 burbs and they had the same compressor listed as mine, I didn't find a different part number or a listing for dual air burbs..

Will a later year R4 be the same mounting as pre 95's are?
 
Same mounting. I posted long ago the R12 and R134a port and hose manifold diffrences. No matter as R12 compressors are NLA and you use thick sealing washers to adapt 1993 R12 hoses to R134a compressors. Guess what blows out when the high pressure switch fails? :facepalm: the sealing washers...

I recall the dual air R4's have a 10 cast in the back. May only stock one part now and be ignoring the dual air part.
 
Bringing up r12 vs r134a and on Chris’ thread-

Ya know how a retrofitted system simply cant get as cold? It’s because of the boil temperature difference and to make it the same output temperature the evaporator has to be 33% larger to make it work exactly the same as original.

Of course pretty much no rig can fit one 33% larger than what is already there unless it gets slightly bigger and thicker. This of course hampers the radiator more, adds more refrigerant which means less efficiency, etc.

So why interesting here? The coating that Chris can do in his big oven, TLTD, gives a 35% increase in efficiency! BAM!!! All original classic car can keep the correct factory part, just finished with TLTD which is going to look perfectly stock even to an expert.

Sorry, no input on the compressor or reat of the system for your truck other than you need to do your stack, evaporator, & heater core when they are out! Turn your rig into a fridge during summer and an oven for winter!
 
Buy a GEP brand compressor. Yes they're made overseas, but they are high quality units(made in Korea and Taiwan, not China). It's what resides under my hood, and the only compressors I have installed without failure in the ladt 5 years or so now. Also make sure you're buying the conversion condenser. AC delco specs 2 condensers last I checked, one for r-12, and one for 134 swaps. And I believe one could swap to the r-134 evap if one wanted to, they arevirtually identical, but the 94+ unit is roughly 3/16" thicker iirc. And I would keep the orifice tube in the evap instead of moving it out to the condenser like GM did in 94. It adds a little more liquid capacity to the system.
 
Will L. said:
The coating that Chris can do in his big oven, TLTD, gives a 35% increase in efficiency! BAM!!! All original classic car can keep the correct factory part, just finished with TLTD. . .
Click to expand...

Ah, the missing secret sauce! Will check this out for my vehicle that was spec'd for R12. Never was the same on 134. Great idea Will, thank you! :D

So, looks like Twisted Steel will get more business when I take that vehicle offline again :)
 
I believe AC Delco comes with a kit for the condenser rubber mounts for the R134a Condenser conversion. (This changes as I ordered long time ago.) If not just order the R134a Mounts. Always check the new condenser for an orface tube so you know what you have. Some come with it pre-installed and some don't.

For some strange reason 1995 dual air burbs have a smaller condenser replacement then the OEM Harrison it came with.

Thread with part number for the seal kit and R134a and R12 hose differences.

http://www.thetruckstop.us/forum/th...pressors-vs-newer-r134a-r4-compressors.39580/
 
Last edited:
WarWagon said:
I believe AC Delco comes with a kit for the condenser rubber mounts for the R134a Condenser conversion. (This changes as I ordered long time ago.) If not just order the R134a Mounts. Always check the new condenser for an orface tube so you know what you have. Some come with it pre-installed and some don't.

For some strange reason 1995 dual air burbs have a smaller condenser replacement then the OEM Harrison it came with.

Thread with part number for the seal kit and R134a and R12 hose differences.

http://www.thetruckstop.us/forum/th...pressors-vs-newer-r134a-r4-compressors.39580/
Click to expand...
The replacement condensers are the more efficient multi pass round tubes vs the original capilary design. I wished I could find a bigger replacement. On a 95 degree day the ac has to work, and my aux fan is roaring away which means the high side hit 283 to trip the switch and is staying over 250 to keep it on. I dont like the high side running that high.
 
@Burning oil posted up using a bigger condenser. Not sure if it was bigger than the said dual air burb unit.

I am happy if I can keep the high side below 300 psig aka 160 degrees F. IMO that's the upper limit of R134a in our FOT systems. System is not putting out very cold air there and at higher head pressure/temps.
 
He used 9ne from a late model f150 iirc. I want to look into installing one from a gmt-800 dual air burb. You would have to make custom hoses, but it should fit semi closely, and has alot more coing area. Or try and find one from a gmt-455 3500hd ambulance and adapt the lines.
 
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