dual oil cooler parts list? what to expect?
 

Just wondering what parts I should expect in a dual oil cooler kit (say, from rotary extreme or even mazda). I just need to know what I should be looking for so that I don't attempt the install without all of the parts in place (don't want to leave the car in pieces for weeks while I wait for the parts to show up).


Cheers,

check out CCW's dual oil cooler kit $900 but theyre huge!

eh, they're not that big...only 19 row. but looking at that pic, looks like a relatively extensive list of parts. I'll ID them and go from there.

CWR (CWC) makes a great kit. Their coolers are bigger then the stock R1 coolers and offer enough capacity for anyone's needs. They sell the entire kit in one package that can be bolted up in one weekend.

Max Cooper did a nice write up on the kit and put it on his website.

is cwr's kit the biggest one availible? i thought it was... i wonder how much cheaper it would be to just buy whatever coolers they use and get hoses/fittings our selves.

I believe that Chuck at Rotary Extreme makes the biggest set on the market.

I looked into building my own but when I saw what was involved in building and engineering a system that would work reliably I decided to buy a kit. I didn't want to have my car down for weeks if not months at a time while I hunted down parts for my do it yourself oil coolers.

This is a major undertaking and purchasing an off the shelf kit saves a lot of time. I went with the CWR coolers because they were relatively inexpensive ($900) and came with everything that was needed to install.

I am not saying that a do it yourself kit is imposible or that there arn't people who are out there who have, but its a big project and it wasn't right for me.

Here is a link to Max's write up on the CWR kit.

http://www.maxcooper.com/rx7/parts_i...lers/index.htm

It does appear that the RE kit is the largest available in a kit at the moment, however the CRW kit nearly doubles the combined size of the stock stuff (assuming r model...more if not). The prices are a bit steep for the RE kit, but the CWR is a bit more reasonable (but still not as cheap as doing it yourself).

Who knows, maybe someone will come up with a cheaper kit someday.

wow those arent amuch bigger than the stockers???? might as well save 900 and get another stock one

The coolers in CWC's kit may not be much physically bigger but they are better designed with more cooling rows than the stockers.

Also, the extra size of the coolers in Rotary Extreme's kit is pretty worthless without an aftermarket front end with large oil cooler openings. Chuck even states that on RE's website.

EDIT: As an aside, you only need upgraded oil coolers if you are running road racing events. They are entirely unnecessary for street driving.

I agree with Rynberg, the coolers have more than twice the rows of fins. Would be a great improvement even for the person who does occational HPDE's.

Does anyone know how much oil capacity the CWR dual cooler system adds over the stock single cooler? This is a huge plus as well. More oil is a good thing.

Not sure of the actual add'l capacity this will add (I'd just ballpark it at about another 1.5-2 qts). Consider this, plus additional oil capacity via a different (bigger) oilpan, and/or some other means of adding another quart or two of oil to your system and pretty soon you're running a 6-7 quart system, which I can only imagine helps with heat dissipation and engine wear (more oil used for the same distance driving means less crap in each unit volume of oil)

I'm definitely looking forward to putting a dual cooler kit on, as well as some of the other things to increase the cooling capacity of this car.

One idea is to put a Amsoil bypass filter kit on. (if it would work??) Gives you 2 additional quarts of oil plus the additional filtration. The oil pan is a good ideal as well. In reality, if the oil coolers give you 1-1.5 quarts additional capacity that is huge. I would stop there.

Link to amsoil bypass filters http://www.amsoil.com/products/bf.html

^ but when you change your oil remember that you are gonna end up with how ever much extra used oil in your system, as the stuff from the coolers doesnt get drained right?

also im planning on using a 99 spec bumper so it will have bigger openings but yeah... i see your point rynberg. maybe if you had a GTC front or something... but otherwise these are probably good. i dont have an extra $900 right now but would like a temporary dual setup for the 20b im building (im trying to cut a few corners temporarily till i can get it installed & running) and i have a stock single and, a large one from the mazda cosmo.... does anyone know if i would need to run an oil thermostat if i rig both up together? also, is the 2nd iol-cooler on the r1 the same as the 1st one (like if i have 2 oil coolers from 2 tourings, will it bolt up the same as an r1)? thanks guys! heath

The thermostat for the coolers is mounted in the driver's side cooler (the coolers are connected serially, not parallel). You have to get a passenger side cooler, they are not the same part for both sides.

That's right. The stock oil cooler holds .5 quarts of oil. I assume the CWR's hold like .75-1qt each. I'm going to e-mail them and ask the question.

ok thakns, i think im gonna just ghetto-rig the cosmo one and touring one together.

wait... if theyre connected in serial then if you close the thermostat then you close off the whole system (maybe im confusing the terms...isnt this parallel:

0==0
| |
0==0
| |
| |

or this:
---0==0
|
---0==0





^ damn you forum!!! sorry its taking some of the spaces larger than 2 out.....

Yes, that's the whole point of a thermostat....:)

They are connected serially. Oil enters the driver's side cooler when the t-stat reaches the temp range (180F, I think) and then flows into the passenger side cooler before looping back to the engine.

wait.... rynberg.... which one is serial in my diagrams? (isnt #1 the correct way? i though that was called parallel? )

#1

0==0
\ . . |
0==0
|. . . |
|. . . |

#2

---0==0
. . . . . /
---0==0

/ = thermostat (please ignore the preiods)

Here are all the part #'s for the stock R1/R2 coolers: http://www.scuderiaciriani.com/rx7/oil_cooler.html

oil cooler options
 

I recently added the CWR dual oil cooler kit to my moneypit/FD (base model), and have been very pleased with it to date. Duane of CWR and I had some discussion about the RE 34-row kit AFTER I had purchased the CWR kit. He stated that based on their test data, 25 and 34 row kits are overkill for the FD. Not bad, just overkill.

Based on all the Corky Bell stuff I've read, the same pricipal applies to intercoolers, or any kind of heat exchanger for that matter. I'm sure Mazda knew that when they determined how big of an oil cooler(s), radiator, intercooler, brakes, etc. in the FD, and decided to put the smallest ones possible to reduce the weight of the car. (See Yamaguchi's book - they were fanatical about weight reduction.) Now the problem is we are taking these street cars to the track and running them on race rubber at high levels of boost... thus generating more heat than a stock RX7, and in conditions a street car would almost never see.

That said, you can still go too far in upgrading all these items (the heat exchangers) based on thermodynamic principles of efficiency. Going beyond that just adds weight.

p.s. Crispy has a nice write up of the CWR kit install on his site as well.

The size of the coolers isn't the only issue. The CWR kit's are larger and more efficient, but they also come with tight-fitting carbon fiber ducts. The stock ones fit like shit, and Chucks RE kit, while the coolers are larger, have no ducts at all. We all no how much better aftermarket radiators work with proper sealed ducting, well, the same principal applies here.

The CWR kit is a very nice kit and works well. I have no complaints.

Ducting
 

Peter is right about the importance of proper ducting of course. Let me tell you, the CWR carbon fiber ducts seal like a mofo - I mean no air, or anything else, gets by them without going through the cores. This means leaves and anything else flying around... so I'd recommend some mesh grillework in front of the coolers. I should post a picture of mine at some point.

i think im going to go with the CWR kit... from what everyone says its constructed very well. i have 2 questions though:

1. Has anyone running this kit seen any cooler temps after the install to back the claim that it "works well" :biggrin: (not trying to be an ass, just wondering if youve seen any differences after installing the kit)

2. why is it so expensive? i found the same MOCAL oil coolers on yahoo shopping for $130 each. i know the carbon fiber must be expensive to produce, and im not sure how much lines would be but $900 is alot of money...im a broke ass hoe :) that being said im probably gonna buy the kit :wink:

Yes, guys have seen oil temps 10-20 degrees Celcius below those with dual R1 coolers on the track.. much more from a crappy old single stocker.... and i've observed lower and more consistent water temps on street and track as a result.

The fittings, lines, brackets, thermostat, ducts, and of course a little $$ for time and research to find and fit it all are what you're paying for... start adding up aeroquip fittings and such, and it gets expensive quickly. I squealed at the price too, but once it was on, i could see how worth it it was.

anyone has cwr website?

Another nice thing about the Mocal coolers is that they are much more durable than the stockers when facing road debris. The fins on my stock cooler were beat flat (no air flow) after 80K miles. My Mocal coolers have a few dings, but are generally still in very good condition after 35K miles.

While the coolers themselves are only $130 each or so, there are lots of fittings, the thermostat, ducts, brackets, etc. None of the parts are very expensive on their own, but there are a lot of parts and the costs add up.

-Max

You could build a dual 25 row oil cooler setup using -10 AN fittings and earl's oil coolers(same core as setrab) for appx $450~

My single 25 row setrab oil cooler "kit" cost me $300(with a total of 6 fittings). It has the same capacity as the stock dual oil coolers and cools better. However, living in Okinawa, I did not have to add a thermostat as the coldest it will get here is 60 F during our coldest winter nights.

Another option is the RZ 99+ dual coolers. They are larger. I've talked to JT-Imports about the specs and getting them...

Yup. You probably could, but as you say, you gotta add the thermostat, some and fabricating costs for *good* ducts.

Never mind that just INSTALLING the dual kit will cost you 6-8 hrs of labor from a good shop... how long is it gonna take you to engineer your own, source all the parts (with no waste or extras), make several prototypes of the ducts first, fab brackets and such?

In almost every thread about M2/ASP intercoolers, sombody points out that you can get a spearco core for $400 so how come the kit is $1400?

Ever looked at the factory cores and ducts? if the RZs are just bigger versions of the same, then no thanks. As mentioned above, for some reason with this kit, just like the M2 intercoolers, everyone wants to find some other solution, or engineer their own... yet these are the best deal.

Pay Duane your $895, install, be happy.

would dual mocal 25 row coolers be any better, or is that just getting stupid?

details details details....
http://www.negative-camber.org/crispyrx7/cwrcoolers.htm

FWIW,
Crispy

No, that's not stupid, that's the way to go. Now, 34 row coolers might be stupid, just because you need some massive holes in your front end to allow for proper airflow to use all 34 rows properly. Stock coolers are pretty small...10 rows, or somesuch, and 25 row coolers are roughly 2x the size, and if you go dual (from a single) you're getting like 5x the size (whether or not that actually equates to 4-5x cooling efficiency, etc. is a matter for our thermo engineers out there).

Definitely it's worth *considering* the dual 25 row cooler upgrade, but the proof, as they say, is in the pudding. Empirical data from the same car with single and then dual coolers would be the best, and dog willing, I'll be able to do that when I have the money for the dual cooler kit.

wow great website! well done on the coolers. i wanted to ask a few questions though. is there any purpose to keeping the oil cooler ducting that exhausts through the side vents in the car (like keeping hot air out of the engine bay)? also, i will be installing a 20b (so i need as much cooling as i can get) and going with a 99 spec bumper which as bigger openings for the coolers... would getting 2 25 row oil coolers make a difference vs the 19's? im just not sure how id make some good ducts for them. heath

A couple points,

1. Install it yourself.
2. Engineer our own? SanJoRX7 and I already have.
3. Ducts? You honestly do not need fancy ducts. Just because CWR likes to do everything in CF doesn't mean you need that level of technology.
4. We already sourced all of the parts, including tstat.
5. Fab brackets? It's an L-shaped piece of sheet aluminum. Use a pair or pliers or a vice with a standard piece of aluminum.
6. We can do the dual 34-row kit ourselves with the exact same specifications for 900-1000$ 700-800$ for dual 25-row Mocals or Earl's.

Do a write up then and give us a build sheet and parts list.

Just one word of "advice" big coolers are wholey ineffective without sealed ductwork. PERIOD. Without ducts they are merely big heat sinks and once saturated they are done. And no a cooler with 5 times the surface area will not give you five times the cooling.
Airflow across the upper region of a large cooler will be much reduced (even if ducted). See a trend here? Ducting is everything and for me the primary reason I went with the CWR setup and NOT those sold by Rotary Extreme. As for assmebling a "kit" on your own yeah sure if can be done...jusy look at the pic of the parts on my website and you can see pretty much everything needed but how much time will you spend developing ducts...Oops did I say the "D" word again? To me the ducts were worth the extra cost over simply procuring
the parts myself. If you are good with FRP then have at it. As for the side vents in the car...might be useful for venting engine bay heat if new ducting is fabbed but for the oil coolers nah...I don't think they do much at all.
Crispy

I think CWR injected you with a syringe of liquified graphite. :)

FPG,

Sure, but the condition is that at the same time you've got to do an equally productive write-up and then we'll both share in front of class.

crispy: interesting point about using the side vents to vent from the engine bay... i wonder if they would actually help... but yeah, now that you mention it i dont see the point of the ducts since the wheel wells woud keep the heat out the engine compartment... what was mazda thinking??

ps i found stainless steel aeroquip size 10 hose for $5.65 per foot, same aeroquip hose ends for $20 each (im not sure how to attach them to the hose), 19 row MOCAL $129 each... or 25 row MOCAL $188 each, mocal 180 degree thermostat $80.

so.... ~10 fittings ($200), 2 19 rows and thermo ($340), say this is just a wild guess 30ft of hose ($170) = $710 ....yeah id pay $200 for the ducts so $900 is an ok deal from CWR

A bit Off-Topic, but you might like these two threads.

https://www.rx7club.com/showthread.p...threadid=60096

https://www.rx7club.com/showthread.p...threadid=31431

does anyone know if CWR makes a duct for the 99spec bumper????

Sorry my friend, I never stated the oil cooler kit won't be effective without an aftermarket front end.

Oil does about 30% of engine cooling. Even if you do not road race your car, it's still good to have it. When it comes to cooling, I like extra assurance especially on a rx7 which is known to have cooling problems.

Chuck Huang

The dual 25 row kit I have is very effective. My customer has the oil temp gauge to monitor the oil temp so it's not just some wild guess. You can PM him and ask him about his experience. His forum name is Tgriesel.

I don't know how CWR determines the 25 row or the 34 row will not do anything better than the 19 row but a 19 row will do better than stock. I can't seem to understand the logic behind this. Unless they can prove their dual 19 row oil cooler kit are so effective that oil temp stays at the thermostat opening temp of 180F, a bigger oil cooler will improve cooling. Any of the CWR oil cooler kit users have some data to share?

The same logic applies to water cooling. If your radiator is effective enough to keep the water temp at 85C (thermostat opening temp), a bigger radiator will not do better but if your water temp is above that, a bigger radiator will help cooling.

As far as ducting goes, there are too many bumpers out there and there is not an universal duct that will fit all of them. My oil cooler kit has the oil cooler sitting very closely to the opening and besdies that, the cooler are wider than stock. Air pretty much has no where to go but through the oil coolers. If you really want some ducting, you can make some yourself with some aluminum sheet metal.

Chuck Huang

Chuck,
Emperical data from my car. I use the ducted CWR 19 row coolers with a OE front end. On the *street* my oil temps sit pretty much dead on the tstat opening temperature - ALWAYS. There is no question the 25 row coolers are effective. Is it better or cost effective upgrade for the street to go even bigger? IMO questionable as the tstat is already governing the temp it is obvious the coolers are already "oversized." Will 25 or 30+ row cooolers be better for the track? Possibly yes. But ONLY if ducted to force the air through the cooler. No matter how close to the nose they are located if you have ANY gaps you're loosing airflow through the cooler reducing it's effectiveness. The ducts are the key. No ducts and the bigger coolers aren't really worth it. .....IMO of course
I do however sympathize with the issue of providing ducts for all the aftermarket noses.

Rotormotor,
You did the same math I did. When you consider the assembly of the hoses and fabricationof the ducts, to me the $200 "premium" for the CWR kit was worth every penny. Plus I got to put more *functional* CF on my car :)

Regards,
Crispy

Have you downloaded the preview issue of rx-tuner lately? ;)

All I am saying is that no one likes it when an idea is waved in front of there face and then not given to them.

A good working do-it-yourself oil cooling system would help a lot of fellow rx owners. It is too late for me becasue I already have one installed.

Both Chuck and Dwane have very nice systems. I have purchased items from both of them and they have been great to deal with and either one can provide you with a suitable ready to install oil cooler system.

I will PM you clayne.

Sincerely,
Jason C. Williams

Sorry I misquoted you a bit, Chuck. Here is the actual quote from RE's website:

"To take full advantage of the monster size oil cooler, an aftermarket bumper with larger openings for the oil cooler duct will be highly recommended. The best bumper that works with this oil cooler setup will be the Mazdaspeed GTC bumper."

I have seen the monster oil cooler setup on Tim's car. They are HUGE!

^ so does anyone know? :)

How about giving CWR a call or an email and find out for yourself?