Metric to AN lines for front oil cooler: where do get them?

[Shaun @ Tru6]

I just mounted a Mazda RX7 oil cooler in the front of the car and need to make aeroquip lines to go from factory hard lines to cooler.

Factory female ID (measured at loop cooler) is 28mm and 1.75 thread. Mazda is 16mm openings and looks to be a 1.5 thread.

Getting metric to AN for the cooler is easy (Earl's Products at Summit Racing), but I can't find an AN conversion fitting for the hard lines.

Any ideas on how this is done?

Thanks

Shaun

[Chuck Moreland]

Shaun

Those fittings on the mazda are too small for your purpose. They should be replaced. Check this earlier thread, particularly the post by TREcup.

[Slider79SC]

Shaun,

I got adapters from The Racers Group that fit on the stock hard lines and were a -12 male for the new lines to the cooler.

[Eagledriver]

Shaun,

Don't mean to contradict Chuck but I think your cooler fittings are big enough. The output hole in the oil pump is only around 12mm or so and -12 fittings are about 14mm and are recommended as the minimum size by some (not all) experts. I have a front cooler with -12 fittings and run Mobile 1 15-50 with no problems. I did lots of worrying over the size of these fittings and did lots of back of the envelop calculations and decided that the pressure would be much lower in the scavenge circuit than the other circuit in the pump even with these fittings.

-Andy

[Chuck Moreland]

Probably would have been helpfull if I actually posted the link
Mazda oil cooler??

Eagle, the 16mm Shaun quotes is not the ID of the fitting - it is the thread size. The ID is much smaller than the typical 14.5 mm ID of a AN12 hose end.

Note also that back pressure is not a weakest-link-in-the-chain function, it is a cumulative. Every orifice, hose, element and bend adds to total backpressure.

Hence a smallish orifice at the pump does not imply it's OK to have similarly small orifices throughout the system. The factory never designed the system that way and in this case it's wise to follow their example.

[juanbenae]

i might try a tractor/fork lift parts place. hydrolic fittings from a metric manufactured machine may be found.

[911pcars]

Pegasus Racing has metric-to-AN adapters right in their catalog. I also think AJ-USA and BAT/Mocal carry them too. Chuck (Elephant) should have them as well.

Hope this helps,
Sherwood

[Mike Feinstein]

That's quite a large opening you've cut into the front pan of your car. Aren't you concerned about structural issues as a result?

Just curious.

[911pcars]

Shaun,
Don't know what your final sheet metal plans are, but I think Dave at TRE has the proper exit air sheetmetal for that opening.

What you're doing is the right way to do it.

Sherwood

[sprbxr]

Gates (the same company that makes hoses) makes metric fittings. If you go to a hose supply store, they can fab up complete lines for you.

[tholyoak]

Bat Inc/Mocal has all the fittings you need
http://www.batinc.net/main.htm
Todd

[Joe Bob]

I have extras.....

[MichiganMat]

Take special note of Chucks comments. Not only must the fittings be large enough, the cooler must have a high internal flow rate to operate correctly. I've fiddled around with a custom cooler setup for a few months now. My car actually ran hotter with the small radiator than it did with the loop cooler because it didn't flow as much oil as the Porsche-specific coolers.

As for your fittings, I canabalized the barb fittings from an old oil line hose that I kept when it was replaced by the cooler lines. I put those fittings into an AN-16 line and had them crimped. When the crimp make sure they use a really tough, heavy duty, crimp because the pressure in those lines will over power a simple brass crimp collar.

[campbellcj]

I could be wrong, but that pic doesn't look like the other "RX7" junkyard coolers I've seen. That thing is huge; in fact as big or bigger than the MazdaSpeed Motorsports (formerly MazdaComp) cooler I have in my 914-6. I have never been able to get the oil temps over 200° since that cooler was installed; and that includes 110F track days. Of course proper lines, ducting and circulation are crucial. I would try to stick with Chuck's advice and do AN-12 throughout. Street cars might be OK with -10 lines but Porsche's are all about "overkill engineering" and the cost delta is pretty trivial...

[Shaun @ Tru6]

thanks everyone for all the great input. After looking at other options, I've decided to go ahead with this cooler.

My plan includes cutting the female AN openings down, welding on Al -12 AN male fittings, then running with -12 line and -12 fittings with 30 to -12 adapters.

I called Pegasus and they set me up with all the fittings and line, as well as a -6 AN kit for the fuel cell.

I will post progress including cost and temps once the car gets going, maybe by end of June.

So far, cost of cooler (shipped) was $110. Cost of lines and fittings: $200. This system will be cooling a stock 3.2.

Chris, there are no part #'s on the cooler. When I called a Mazda RX-7 specialty yard, I asked for a 91-92 RX-7 Turbo cooler and told them it was going into a track car, so who knows what I really got.

[MichiganMat]

eBay is loaded with AN- braided lines, all from NASCAR teams. Do a search for NASCAR in the auto section and you should be able to find a bunch of premaid lines with fittings for pennies on the dollar.

[911pcars]

Here's one source for used fittings. Their new prices aren't a bargain, however.

http://www.musclemotorsports.com/aeroquip.html

Sherwood

[raceman]

l have the exact same cooler on my 84 3.2 and it works great,even without the relief ducting cut out from behind.l know that`s the way to go but since cooling hasn`t been a problem l don`t intend to start cutting just yet and l`ve got my A/C system to consider also.As for fittings a had the local Earls dealer make the hoses at less then $100.00