Double oil cooler sandwich?
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From: San Antonio, Texas
So right now I have two stock oil coolers in my possession. There is a lot of room between the outside end of the oil filter and the frame. So I was wondering... What about stacking two of the oil coolers for some extra oil cooling?
The plumbing for the the coolant can be fed in parallel. I think I can make it work mechanically with the filter fitting tubes, so I am wondering more about the thermodynamic behavior. I have an oversized radiator so shifting the heat load to that should not be an issue.
Anyone tried it?
The plumbing for the the coolant can be fed in parallel. I think I can make it work mechanically with the filter fitting tubes, so I am wondering more about the thermodynamic behavior. I have an oversized radiator so shifting the heat load to that should not be an issue.
Anyone tried it?
Yeah, stud length would be an issue. My Mocal uses a special nut that threads onto the end of that stud, and then the filter threads onto that.
I'm not even using my stock oil cooler on the new motor.
I'm not even using my stock oil cooler on the new motor.
Doesn't each oil cooler have a stud like that? If so, one can install as many of those as he wants just like he can install multiple Mocal plates ...
He's talking about the stock cooler, which uses the long stud coming off the side of the engine. There's no Mocal spacer-style nut; it just slides onto the stud behind the filter.
interesting....I was going to install a stock 1.8L oil/water cooler last weekend but couldn't find a second nut to fit on it to try to remove the stud. Sounds like this would work to install the cooler, as I got annoyed and said **** it.
btw, cop bracket is butterz, thanks.
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Elite Member
iTrader: (15)
Joined: Dec 2007
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From: San Antonio, Texas
Yeah Sav is right that is how it goes on.
I thought there might be enough clearance to use an intermediate joiner nut between two stock tubes, not sure about that yet. I have not searched for a hollow 'all-thread' yet, though if I could get a solid threaded rod of the right size and pitch (McMaster?) I know a machinist who would center drill it for me.
I thought there might be enough clearance to use an intermediate joiner nut between two stock tubes, not sure about that yet. I have not searched for a hollow 'all-thread' yet, though if I could get a solid threaded rod of the right size and pitch (McMaster?) I know a machinist who would center drill it for me.
I suspect that the stockers (even 2 of em) aren't that effective in transferring heat. As a warmer, it'd work better, because during warmup there may be 70*F temp difference between coolant and oil. When the oil is hot, it may only be 40*F hotter than the coolant.
Has anyone dissected one?
Has anyone dissected one?
I think its a bad idea. Those are very restrictive to oil flow. The oil has to go through soooo many small passages. it has to pass thru each small sandwich thats in there. It doesnt go straight through at all. I took mine off.I wouldnt do 2. Unless you dont ever see high RPMS..
Yeah, I know he is talking about the stock one. I just never ubolted mine so I was not sure whether they just added an extra spacer nut over the same stud as in the oil coolerless B6 engine or just replaced the original stud with a longer one.
Last edited by j_man; Mar 17, 2009 at 04:08 AM.
Btw, has someone dissected a OEM Miata oil cooler? Bigger ones might exist in the Mazda part bins.
In the past I remember reading at various web sites about Mazda 323 GT-R talking about bigger OEM oil cooler. I just googled some to fresh up memories and found this:
"The new five-stage water-cooled oil cooler has a greater capacity over the GTX's old two-stage unit."
it is from this site with lots of original info about the 323 GT-R:
Untitled Document
(click at the labels at the scheme at the bottom to get to the rest of the sections. the oil cooler mentioning is in the Turbo & Intercooler one)
In this forum thread a 3 stage is mentioned about 1.8L US engines (I guess Miata & Proteges):
"1.8l's in U.S> stock form has a 3 stage stock oil cooler....the GTR block has a 5 stage....."
http://www.mazda3club.com/showthread.php?t=26549
So .... does anyone know if the Miata oil cooler is the 2 stage one, 3 stage one or the 5 stage one?
Also I remember reading somewhere online about the Mazdaspeed Miata having 30% bigger oil cooler. Not sure if it is true or a myth - maybe we should check the part numbers for the MSM and compare to the previous ones.
In the past I remember reading at various web sites about Mazda 323 GT-R talking about bigger OEM oil cooler. I just googled some to fresh up memories and found this:
"The new five-stage water-cooled oil cooler has a greater capacity over the GTX's old two-stage unit."
it is from this site with lots of original info about the 323 GT-R:
Untitled Document
(click at the labels at the scheme at the bottom to get to the rest of the sections. the oil cooler mentioning is in the Turbo & Intercooler one)
In this forum thread a 3 stage is mentioned about 1.8L US engines (I guess Miata & Proteges):
"1.8l's in U.S> stock form has a 3 stage stock oil cooler....the GTR block has a 5 stage....."
http://www.mazda3club.com/showthread.php?t=26549
So .... does anyone know if the Miata oil cooler is the 2 stage one, 3 stage one or the 5 stage one?

Also I remember reading somewhere online about the Mazdaspeed Miata having 30% bigger oil cooler. Not sure if it is true or a myth - maybe we should check the part numbers for the MSM and compare to the previous ones.
Last edited by j_man; Mar 17, 2009 at 04:09 AM.
I just checked the 2005 Miata diagrams at Mazda Motorsports and the oil cooler for Mazdaspeed Miata has a different part number!
2005 Miata:Then I opened the part diagrams for 1994 Miata:
All BP Miatas have the same OEM oil cooler except the MSM. And I guess the MSM one is bigger. How much bigger (maybe the 5 stage unit?) - someone buy one and post pictures 
Here is the 2005 parts diagram:
2005 Miata:
14-700
BPE8-14-700
COOLER,OIL
$157.33
Start DateEnd Date Notes: W/O TURBO
14-700
BP5C-14-700A
COOLER,OIL
$115.12
Start DateEnd Date Notes: W/TURBO
BPE8-14-700
COOLER,OIL
$157.33
Start DateEnd Date Notes: W/O TURBO
14-700
BP5C-14-700A
COOLER,OIL
$115.12
Start DateEnd Date Notes: W/TURBO
So, looks like it is true
All BP Miatas have the same OEM oil cooler except the MSM. And I guess the MSM one is bigger. How much bigger (maybe the 5 stage unit?) - someone buy one and post pictures 
Here is the 2005 parts diagram:
Last edited by j_man; Mar 17, 2009 at 04:35 AM.
I have what I believe is the GTR cooler. My block was a gtr.
In fact, I will have a 01 a 1.8 na cooler and the gtr to compare. I think they are all at my machinist's shop..
I will take pics.
In fact, I will have a 01 a 1.8 na cooler and the gtr to compare. I think they are all at my machinist's shop..
I will take pics.







