Vibrant, Earls, Fragola, others make the M18x1.5 to -10an adapter in aluminum. Anyone withe the sakebomb dual oil cooler kit is probably familiar with why this isn't a good solution. The way the oil thermostat is designed (Steel) and the -10an aluminum fittings that hang off the front cover support the thermostat. There's a bracket that's supposed to support it, but as you tighten the fittings down you'll note the thermostat tends to twist and put a great deal of stress on the aluminum fittings that support it. My oversized meat hooks don't work in inch lbs and I tend to crack the conical surface inside the 90 -10an fitting when I assemble the parts.

The design of the kit is pretty close to being good, but these fittings need to be steel given the stress they are under, with no flexible line between the thermostat and front cover. I think Mocal at one point did make an M18x1.5 to -10an adapter but I can't seem to find it. M18 to 10an tends to be a popular power steering fitting so I know it's buried in a catalog out there somewhere. ICT billet comes really close with a female m18 to 8an, but no male m18 to male 10an. Anyone else have a source for these?



Front cover fitting:

 

Oil Hose Adapter Fitting for 18MM to -10 Hose - Racing Beat

 

Brother! Thank you for that. I feel dumb because I just put an order in with them a few weeks ago, should have ordered these too.

I installed their Rx8 oil cooler line kit on my wifes R3. Great kit, but holy **** want a pain in the *** to install. Fragola wanted a minimum 1500 unit order, not sure I could resell that many units.

 

My Crooked Willow Racing (CWR) dual oil cooler kit has a similar setup, years and thousands of miles of use, street and track, and never had any issues. I did not use the thermostat bracket though, it is just free floating and can move with the engine, maybe this made a difference.

Also, you can use the counting flats method for tightening 37 deg AN connections, consistent tightening every time no torque wrench needed.


JIC is a 37 deg flared fitting interchangeable with AN fittings.

 

When you say JIC 37 degree flare fittings interchange to AN - is the same true for SAE 37 degree? And what is the interchange? Trying to find a chart on google but nothing clearly says -10an is (what I'm guessing to be) JIC 37 7/8th

 

 

Thanks all for the help. To bring this conversation full circle here is the final product: Really happy with this solution. The aluminum AN fittings are not sufficient to support the weight of the mocal thermostat. The bracket is pretty flimsy which puts stress on the taper which leads to leaks. None of these SAE/JIC fittings were more expensive than their vibrant AN aluminum equivalent.

 

Nice! That's exactly how mine sits but I don't use a bracket. The hoses from thermostat to coolers provide additional support. I'm using steel braided with heater hose on top to prevent abrasion.

 

I'm no mechanical engineer, but that bracket does not inspire confidence. How many hours/miles have you put on it? Now that you've replaced aluminum fitting(s) with steel, what will be the next weakest link when the thermostat vibrates and tries to torque on the fittings? Is there not room to mount the thermostat near the driver-side oil cooler since the lines need to go there anyway?

 

1200 miles, the front cover, maybe, but this is the way the sakebomb kit is designed. I'm not a huge fan, but it's what I'm gonna go with at this point. It Doesn't play well with low pressure ac line either.

 

You can avoid all this by simply putting the thermostat in line between the two oil coolers. That eliminates any engine vs chassis movement by bolting directly to the chassis. As long as your oil coolers are plumbed in series, it will function normally.

 

@F1blueRx7 I wanted to checkin and see how this has held up over time? I installed the Sakebomb kit with -10 lines around the same time as you in 2021 and haven’t had any issues.

But now, I am in the process of adding back powersteering and AC. I noticed that the thermostat would have to be moved put of the way to install the idler bracket, and I started thinking of someway I could introduce some flex between the front cover and the thermostat. So far, I’m hoping to run a banjo from the front cover and a short braided line to allow some give between the motor and the thermostat- but curious if your method with the steel fittings is sufficient.

 

Works great. I did replace the thermostat with a billet unit from Improved racing. Really nice upgrade over the mocal.

 

@F1blueRx7 Cpuld you share some pics of your new thermostat and where you placed it?

 

Just dropped the engine back in and here's some pictures, it's supported by the steel fitting in the front cover, no issues. The aluminum block doesn't weigh much.

 

I can’t understand why it’s not set up that way.
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I guess lines are longer. I'll be going with the improved racing remote filter thermostat combo. Plan to mount it on the frame rail, will be mounting that last though, need to make sure location doesn't conflict with everything else.

 

Race Only pedestal adapter

 

Partially because I'm not going to pay to re-plumb everything when this problem was resolved with a single fitting. I bought the kit from SBG, and like several of their parts, in hindsight, there are far better and less expensive ways to build it.

in the current configuration it does work really well. With the OEM A/C Compressor it was a much tighter fit.

 

I get that, but wasn’t making reference to you; only referencing the kit relative to it being supplied the way it is rather than the other.

I bought the Improved Racing t-stat bypass/remote filter setup for my RX8. I’m not comfortable at all just dumping it back into the pan rather than directly bypassing it back to the pedestal on the rear iron.
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Which setup dumps to the pan?

 

the one my you-big-dummy head conjured up, I was just taking a break working on the car and not thinking straight when I fired that off.



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