Looking for ideas on how to mount power steering pump
 

I've obtained an MR2 Power Steering pump use in my RX-7.

Let's not turn this into any kind of power steering debate, I am just looking for ideas on how to mount the pump.

Where I would like to mount it is underneath the back of the car, on the bottom side of the spare tire well.

This is next to the Radium Surge tank as seen in the attached pics.

Any ideas how best to mount this?
(there is also an attached pic of the pump)

Outside the cabin is preferable simply because the plumbing is easier, the high pressure line would remain beneath the car, with only the high pressure lines routed inside for the reservoir.

That, and that pump is rather loud.

I am thinking of using the rear wiper tank as the P/S reservoir, as there isn't a rear wiper or any of the mechanisms, and the tank is already there.

Interesting project. A couple (hopefully more useful) thoughts:

1) That's a long way to run a hydraulic line - how much pressure does the pump produce (or does the rack need?). Remember that pressure drop is proportional to the line length so you may need to go with a slightly larger than stock line to maintain flow. Hard lines are probably better here.

2) I would be wary of using the washer reservoir for hydraulic fluid - not sure if the plastic is compatible. Try finding a surplus reservoir that will fit in the same location.

3) Remember that you will need to provide some sort of cooling loop up front. Also, you will need to insulate the lines from the exhaust as they come forward.

4) Does the pump require any sort of air flow around it to keep it from overheating? You may need to duct some under-car air around it (probably not a bad idea period).

5) Considering the complexity and all the additional weight of the lines, I would almost consider keeping the pump up front if you have room under the hood on the driver's side. I am assuming that you have relocated the battery? Is there room there?

Let us know how it goes.

-bill

It's been done this way, I know someone with a Miata that has located the same pump in the trunk.

I guess it's time to pull out the automotive math book.

Good point.

Already using a Setrab cooler, planning to continue doing so.
The lines will run on the left side of the car, and I will include a heat shield between the pump/fittings and exhaust.

I had thought of this. Ducting air around it may be helpful, or just installing a small fan.

It may be a good idea to just install some heat stickers on it and see what kind of temps it sees.
As this car is mostly for autocross, I don't expect heat to be a big issue.

Also something I have considered.
While I would love to keep this thing out of the engine bay, it would probably fit.
Relocating some weight further back sure would help out launches and corner exits though.

Will do.

are you trying to do this without welding?

I welded up a quick bracket for mine. took a paper template from the end that has the two bolt holes and the fittings. cut some metal. then welded it to a flat plate and made some bracing. then I put a piece of flat stock on the other end and drilled it for the hole in the rubber boot. I then welded the whole thing into my trunk area. works fine. you shouldnt need any larger lines or anything. I think I just used -6 line.

Welding would be ok.

Can you post a pic of your setup?

Not sure of how much help it will be. I went down the path of the MR2 pump with integrated reservoir to simplify things. ( no separate reserviour) Also mounted it in the engine bay. (Gen 1) Was able to get it quite low and also allowed short pipe runs, short cabling runs etc. very happy with how it works.

Attachment 633479

Thanks for the pics.

I see you went with the pump from the MR2 Spyder.

Seems like a good move, lighter and takes a lot less space.

Hmm...

Thread Cleaned up as per request.

Does anyone have any info on the 1st Gen MR2 setup..on an FC?

I got a new S5 rack and a 1st gen Mr2 pump..NOT the Spyder integrated one..(separate reservoir)

Never thought I would thank a Wang for pics..lol!

Thanks for the cleanup!

I do have a couple FC thread URL's

AusRotary.com ? View topic - FC power steering questions?

https://www.rx7club.com/fabrication-...ersion-847818/

If I were using the MR2 pump* in the location you want-
I would remove the stock rubber dampers and make a 90 deg bracket that bolts to those damper locations and runs the length of the pump. Then I would re-use the stock dampers at either end of the bracket to mount through the bottom of the spare carrier.

I don't know if that would leave it hanging too low for you though.

* I did look into this and decided I would use the MRS pump near the rack if I ever did the conversion.

What I have in mind is pretty much what you are saying.

The MRS pump is sounding like a good idea.

But I already have this one :scratch:

But I already have this one

True, but you haven't yet put time, effort and money into making the MR2 pump work- so maybe it is a good point to switch to MR-S pump if you are leaning that direction already?

Possibly.

The MRS pump might fit in the engine bay.

But I am really looking forward to moving weight to the rear as well as getting a little more room in the engine bay.