I need to install one of these. What size would be best? Would just a double pass be enough? Can I use hose barb or would going to AN fittings be best? Where is a good location? Also I am curious about the stock cooler that some cars have maybe I could make a system like that.

 

GM stopped making the C4 PS cooler units but you could probably find one from a Corvette salvage place.

There are aftermarket PS coolers available and you plumb them into the return line, no the pressure line. Some are single pass units and some double pass. The best place would be in the stock location (in front of the rack. Fab some brackets and bolt the assembly to the existing braces.

I found these Perma-Cool units at Summit Racing. If the link doesn't work, go to www.summitracing.com and do a search on "power steering coolers".

 

Aardwolf,

The picture below shows what I did for a PS cooler, the white arrow points to the PS cooler mounted in front of the front cross member. I bought a Hayden PS cooler and mounted it where the factory cooler is mounted on the later C4's. I plumbed the cooler into the low pressure return side of the system, route the fluid out of the rack into the cooler and then from the cooler into the fluid reservoir. In conjunction with a set of underdrive pulleys I no longer have any PS over heating at the track.

Brian

 

That helps a lot, thanks. Putting a cooler there will be my next project.

Anyone put in an oil cooler to? I have my trans cooler out in front of the radiator but my oil temp can still get high. Would an EOC in addition to the stock oil warmer be best?

 

Aardwolf,

Here is a picture of my oil cooler mounted in front of the radiator. The second picture shows the oil cooler adapter and some of oil line routing that I used. Since this picture was taken I have routed the oil lines closer to the engine block and farther away from the header tubes. Hope this is helpful.

Brian

 

Great! How much did that lower your temp? Also, is that the stock oil cooler adapter or did you have to get a different one?

 

Aardwolf,

I have been running this oil cooler for about 12 years now. When I first started tracking the car, with the stock oil cooler, in 2 to 3 laps I was seeing 280°F oil temps, so I would have to take a couple of easy laps to let the oil temps drop. After putting on the cooler I can run hard for a 20 to 25 minute session on hot days and I will see 260°F oil temps. So it was a worth while investment. The adapter is an aftermarket unit.

The stock oil cooler also mounted between the oil filter and the block, but it is plumbed into the water coolant, water came out of the block just ahead of the oil filter then went into the oil cooler and routed back into the heater hose system. The stock cooler was not sufficient for track use in my experience.

Brian

 

As far as I know, the '91 GM C4 Power Steering Cooler is no longer available. If you live in a hot area like southern Arizona or most of Nevada, I would be careful about using an aftermarket cooler, since they typically are two pass units that are much smaller than the GM factory units. The GM factory unit is a four tubing pass unit and is about 20 inches wide and 4 inches deep; it mounts easily with 4 bolts to some factory brackets that are located just below the front subframe. I am not sure if all C4s came with these welded on brackets, but mine certainly did.

Rather than going aftermarket, I would suggest calling a quality Corvette recycler and getting a 4 pass GM unit that is correct for your car. Be careful, there are some differences from year to year. My OEM '91 cooler had both entry and exit points on the driver side of the car. While the $20 cooler that a recycler shipped me from LA had the input line from the rack on the driver's side, it had an exit line (that goes back to the resevoir) that was on the passenger's side (different than mine).

However, it was simple to route a 3 foot length of 3/8" low pressure PS hose from the passenger side of the car to the return opening on the PS reservoir. In doing this, I eliminated GM's strange OEM "S-turn" hose that snaked around the front sub-frame. This should help with future leaks, as there are now two less hose clamps and one less rubber hose in the system.

In doing my replacement, I took the alternator out so that I could put a new right angle hose fitting with a new hose into the exit fitting from the rack to the cooler and clean things up a little more easily. My OEM PS cooler had been damaged and was leaking from its encounter with a largish western desert road rock.

If I had to put another OEM cooler in and my inlet hose from the rack to the cooler was definitely not leaking, I would just do everything from below the car and use doubled-up hose clamps on the two rubber hoses that route to/from the PS cooler. That job would have taken much less than an hour.

I didn't have any problem in priming the old pump after re-installing the reservoir and routing the new hoses to the cooler. Running the engine about 2000 rpm and moving the steering wheel lock to lock about ten times over ten seconds seemed to do the trick. It was very hard to move the steering wheel before the pump primed itself. I couldn't imagine driving the car without power steering.