Miata cooling system thread
#501
What I'm talking about is that the FAB9 mounting position is right up against the mouth of an NA bumper cover. Leaves very little room for any air to get around the IC (small slot at top with Stage 1, probably nothing with Stage 2). It's also a thick/dense bar and plate core. I've been thinking about doing some Sixshooter style bumper support surgery to open the gap at the top, but am going to try relieving engine bay pressure first.
#502
So bypassing the intercooler some will reduce the pressure differential through the intercooler itself right? Basically it's just acting as a sink now with less forced convection for heat exchange?
I was tempted to just remove that chunky black bumper thing on my car, but I have a begi #3 (with a big vibrant intercooler sitting on stand by). No gap from the front bumper because I retained that small plastic trim that sits in the mouth of the bumper.
When folks duct the radiator, do they just worry about the sides, and bottom, without sealing anything against the intercooler; intercooler just sits idly in space between the mouth of the bumper and radiator, with air flowing freely around and above?
I wonder if teasing out a couple rows of the high density fins will help facilitate flow through the larger intercoolers while still exchanging some heat if it's just acting as a sink at this point. I can only imagine how well a gummed up, bug jammed, fin bent third hand begi #3 will flow after multiple years of use.
I was tempted to just remove that chunky black bumper thing on my car, but I have a begi #3 (with a big vibrant intercooler sitting on stand by). No gap from the front bumper because I retained that small plastic trim that sits in the mouth of the bumper.
When folks duct the radiator, do they just worry about the sides, and bottom, without sealing anything against the intercooler; intercooler just sits idly in space between the mouth of the bumper and radiator, with air flowing freely around and above?
I wonder if teasing out a couple rows of the high density fins will help facilitate flow through the larger intercoolers while still exchanging some heat if it's just acting as a sink at this point. I can only imagine how well a gummed up, bug jammed, fin bent third hand begi #3 will flow after multiple years of use.
#503
The theory about gap between heat exchangers is mainly to give the air room to change direction if needed.
What I'm talking about is that the FAB9 mounting position is right up against the mouth of an NA bumper cover. Leaves very little room for any air to get around the IC (small slot at top with Stage 1, probably nothing with Stage 2). It's also a thick/dense bar and plate core. I've been thinking about doing some Sixshooter style bumper support surgery to open the gap at the top, but am going to try relieving engine bay pressure first.
What I'm talking about is that the FAB9 mounting position is right up against the mouth of an NA bumper cover. Leaves very little room for any air to get around the IC (small slot at top with Stage 1, probably nothing with Stage 2). It's also a thick/dense bar and plate core. I've been thinking about doing some Sixshooter style bumper support surgery to open the gap at the top, but am going to try relieving engine bay pressure first.
Fab9 mounting position leaves like half an inch between interior plastic bumper and i think that's the main reason of my overheating problem. I've yet to decide, if i should tilt the IC or move it back flushed with the A/C condenser. Either solution require custom A/C piping to remove the dryer away from it's original position. Problem is i can't find witch would be the more eficient solution, and if i should separate ducting, restricting like 1/3 of the mouth to de IC and 2/3 to the radiator. I'm @ like 50º IAT after 20min session on a 32º day, so 'm willing to sacrifice some IAT to get my coolant temperatures down.
#504
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I have been having the same questions. I am seriously considering remote mounting my A/C receiver so I can move the I/C back and get some flow around it. I am going to pull the bumper cover first and see if I have air bypassing the radiator, and if not, then I will move the I/C back. If I do have air bypassing, I will seal it first.
Could another experiment be running without the bumper cover?
Could another experiment be running without the bumper cover?
#505
I was looking at remote mounting the accumulater/dryer (on NA). I'm wondering if I can get away with flipping the hardline that connects to the drier to attach directly to the condenser, then mating the drier up directly to the high pressure line after some hardline mangling. Looks like a 16MO fitting on both those hardlines.
Or maybe we can pitch a solution ala SADFab. I know the early Protégé drier shares the same fittings and have a slightly shorter body.
Or maybe we can pitch a solution ala SADFab. I know the early Protégé drier shares the same fittings and have a slightly shorter body.
#507
I was looking at remote mounting the accumulater/dryer (on NA). I'm wondering if I can get away with flipping the hardline that connects to the drier to attach directly to the condenser, then mating the drier up directly to the high pressure line after some hardline mangling. Looks like a 16MO fitting on both those hardlines.
Or maybe we can pitch a solution ala SADFab. I know the early Protégé drier shares the same fittings and have a slightly shorter body.
Or maybe we can pitch a solution ala SADFab. I know the early Protégé drier shares the same fittings and have a slightly shorter body.
Problem is i'm not confortable "massaging" the lines that much, and as i'm no A/C expert and i haven't managed to find if i can crimp rubber lines, or any other type of line a normal hidralic shop could make.
But basicly, this could be the solution (if the problem isn't the A/C condenser per se), from what i can see in my temperatures log, i'm not that far away from managing a full 20min track session.
Other doubt that i have is if i should remove, or at least have some kind of water tap, to the oil/water "cooler" for track time beacause my coolant/oil temps are correlated and i can't understand if oil is heating the water or is just the engine heating all over the place.
#509
I know nothing about A/C systems :S
Here you have more pictures:
and more here: https://www.miataturbo.net/diy-turbo...-79849/page27/
Here you have more pictures:
and more here: https://www.miataturbo.net/diy-turbo...-79849/page27/
#510
Ok, the drier is slightly different on the NB. I wonder if I can use an NB drier on the NA or if there's enough hard line for the NA drier to work. I'm still not convinced about the orientation of the drier, all applications I see have it sitting vertically, I don't know how it works so I don't know if this is a deal breaker. Stack height from that location would otherwise make the normal drier protrude downward below much of the existing hardware on the car, hence the interest in using the protégé or 626 driers as the canisters are physically shorter (albeit, not sure about whether the connections are 100% the same)
#512
Ok, the drier is slightly different on the NB. I wonder if I can use an NB drier on the NA or if there's enough hard line for the NA drier to work. I'm still not convinced about the orientation of the drier, all applications I see have it sitting vertically, I don't know how it works so I don't know if this is a deal breaker. Stack height from that location would otherwise make the normal drier protrude downward below much of the existing hardware on the car, hence the interest in using the protégé or 626 driers as the canisters are physically shorter (albeit, not sure about whether the connections are 100% the same)
The only incompatibility between receiver/driers is that units made for R-12 use a different desiccant than units made for R-134A. I "think" the mandatory switchover year was 1995, so as long as you're perusing a catalog for 1995 or newer cars . . . .
#513
That's neither an NA nor an NB receiver/drier. It looks like he found and sourced a receiver/drier that was designed for horizontal mounting.
The only incompatibility between receiver/driers is that units made for R-12 use a different desiccant than units made for R-134A. I "think" the mandatory switchover year was 1995, so as long as you're perusing a catalog for 1995 or newer cars . . . .
The only incompatibility between receiver/driers is that units made for R-12 use a different desiccant than units made for R-134A. I "think" the mandatory switchover year was 1995, so as long as you're perusing a catalog for 1995 or newer cars . . . .
I'm positive that's an NB1 A/C drier, look at the mounting tab location. Normally it's on the condenser vertically.
Look up: NC10-61-500A
#514
94 they started using r-134a hardware. The pressure switches and the actual compressor and fittings are different on the compressor side. I had to swap my softlines and went ahead and changed the hardlines as well. I couldn't get an r12 compressor; car wouldn't hold vacuum mating the high pressure and suction hose to the r134a compressor using the older style line. I have one of the last MAZDA OEM ones sitting in my car right now so the car has been retrofitted entirely to r134.
I just need to get the pigtail for the pressure switch off a 94+ as they activate under different pressures. I didn't realize the desiccant was different between the years and will then use the later NA8 drier (thanks for the info). All the fittings are the same otherwise, but DNA54 was building an NB upon further investigation. His drier and hardlines are different.
Question remains: Does it matter in which orientation the drier sits?
I just need to get the pigtail for the pressure switch off a 94+ as they activate under different pressures. I didn't realize the desiccant was different between the years and will then use the later NA8 drier (thanks for the info). All the fittings are the same otherwise, but DNA54 was building an NB upon further investigation. His drier and hardlines are different.
Question remains: Does it matter in which orientation the drier sits?
#515
Receiver/driers are designed for either vertical or horizontal mounting. Basically, this is how they separate the gas and liquid refrigerant states. If you flip the reciever/drier on its side, you'll be taking more gas to your expansion valve, which will reduce cooling in the evaporator.
I think you're better off finding an R134A receiver/drier from another car designed for horizontal mounting. Something like this: More Information for ÜRO PARTS MMD7410AA.
#519
Yes, I have an A/C condenser. What do you mean by bulky plastic bit? There was a part that originally went from the front of the under-tray to the lip of the nose (or abouts) that had to be sacrificed to allow the first (ebay) intercooler to fit. I now have what is essentially coroplast ductwork, but it's still too tight to the bottom or the intercooler for my taste. There isn't enough space for air to go around the intercooler in my opinion.
On my way to tail of the dragon last year I was seeing 235 degrees (before I shut the A/C off) in 65 degree wet weather. It was damn scary because I couldn't see without the defrost on, but as soon as I turned the defrost on the temperature started climbing. With A/C off the temp at cruise was between 210-220 degrees.
On my way to tail of the dragon last year I was seeing 235 degrees (before I shut the A/C off) in 65 degree wet weather. It was damn scary because I couldn't see without the defrost on, but as soon as I turned the defrost on the temperature started climbing. With A/C off the temp at cruise was between 210-220 degrees.