i'm thinking about using a Gen III oil cooler in my 84 GS. i don't have any numbers on it's capacity and i wanted to start there, by comparing the difference between my '81 cooler, my '88 cooler and the stock '93-'96 coolers capacity. there is very little difference in capacity between my '81 and '88.
i've done some research and got the common cooler upgrades that the Gen III guys seem to run. i've heard good reports on the CWR and Mocal units, although the Mocal units seem pretty expensive - like $ 1,400 - OUCH
i'm fairly sure that i don't have enough space in my nose to run dual coolers (plus it might be overkill for my setup ) but if i can run one of the Gen III units or upgrades i think it should be good for me. my questions are:

1 - has anyone on this board done this upgrade?
2 - what is the capacity of the FD oil cooler(s) stock, CWR
and Mocal?
3 - anyone have the physical dimensions of them? (judging from the pictures i've seen, it looks to be about the size of the FB A/C condensor)

thanks for any help you guys (and gals ) can provide.
d1

 

1) i dunno
2) i dunno, not as much as the fb,fc
3) the stock coolers are about 8"x6"x1.5" , ive have read that they have about the same area as the fc ones do
think its a lot of extra work for very little gain, the air to liquid ones are ecellent coolers, as long as it gets air flow that should be all you need

mike

 

thanks for the dimensions. i will use those numbers and make my comparisons.

actually, the consensus on the air-to-liquid intercoolers is that they are absolute rubbish. they are barely sufficient for the stock 12A's, and they impose a greater load for the antifreeze and radiator. i can vouch for this, having used them before. they were never used on 13B's by Mazda, so i'm not going to go that route with my motor.

you may be right when you say that the gains may not be worth the effort for what i'm hoping to accomplish. this is why the volume data is so important to me. i already see that the surface area data is in the same general ballpark as the coolers i already have. based solely on that data, using a Gen III oil cooler is NOT going to work wonders over my current setup.

 

exactly. i had a gauge on my fd (r1) and those coolers didn't impress me =)

mike

 

what sorts of temps were you getting? i read where guys were measuring 165*F-175*F with the CWR coolers. how much were you running with the stockers?

 

Ok.... ALL rotaries except for '83-85 12As had air oil coolers. '83-85's had the awful NON-air cooler, that cooks the oil and causes the engines to leak oil like a sieve because the oil cooks the dowel O-rings.

8x6x1.5 for an FD oil cooler?? That sounds like less than half of what a '79-82 oil cooler is!

 

well, i had multiplied what i got from the values he gave to me by 2, assuming that the models with twins (R1 and R2) have different units than the models equipped with only one. i may be wrong ... it was just an assumption on my part.

anyway, i measured both my oil coolers. i got 4.75 X 22.0 X 2.0 (inches) for my '88 unit. the '81 is on the car so my measurements are approximate. i got 4.5 X 20.0 X 2.0 (inches).

figuring that the part of the cooler that is in contact with the airflow is one of the more important calculations, i made my calculations for frontal surface area only, so the depth measurements were not used. i didn't think the depth measurement could help me figure the internal volume, so i figured it was useless to me. i know that when i drained my '81 cooler the last time, it was about 0.66-0.75 quart. i don't know if these assumptions are right or wrong ... but it's what i did.

so for the '81, i got 4.5 X 20 = 90 in.^2
and for the '88, i got 4.75 X 22 = 104.5 in.^2
based on the numbers supplied by j9fd3s (which are the only numbers i have), 8 X 6 = 48 * 2 = 96 in.^2

if these calculations are way off, or insignificant, please point me in the right direction.

thanks,
people!

 

Oooops!
actually, i just realized that the numbers for the '81 and '88 should be slightly smaller because i measured the coolers from end to end, not just the finned area. so i will get some new numbers, simply because i'm **** about these things ...