qkaqk

iTrader: (1)

Hi,
I got my first rotary few months ago, and I feel
it's time to upgrade my baby.
I'm a college student, so don't have enough money for many mods.
I don't feel any lack of power, so consider to mods cooling system first;
then, I can increase power without heating problems.
Also, I sometimes have problem with heating.
Like, water temp increased up to 230 F when I drove low speed or
idle for long time.
However, I consider to mod for cooling system
Here are my questions for cooling mods

I have 93 Rx7 Fd3s

1. Can I make dual oil cooler with buying another oem sotck oil cooler?
(If I can, what otehr parts do I need with it?)
2. I also think to change Koyo radiator, is it enough cooling system with stock engine system?
3. What is the better? Koyo radiator or bigger intercooler? (V mount or FMIC)

Also Extra question
-Where can I find stock parts (without ebay)
I want to find stock FD passenger fender, but it's really hard to find it.
give me any ideas if you need fender (like change for Fiberglass body kit fender or junk yard?)

rseamon

For all stock parts at the best price call Ray mlloy Woodbridge Mazda/ Ray 703-643-2936/490-8170 . Regarding the upgradesradiator vs Intercooler you really cannot compare because its 2 completely different systems. If you are mostly interested in reliability get gauges: Boost, Air/fuel, oil temp, water temp. This will give you a better idea on what you need next...maybe

Sgtblue

iTrader: (16)

It's helpful if you list mods, but based on your post I'll assume you already have an aftermarket temp gauge. That's good, since the stock gauge isn't linear and is worthless. If your car is stock, you don't need any other gauges.
For cooling:
*Drain and flush your coolant. Re-fill with as high a ratio of distilled water to coolant as you can safely do for your climate. The more distilled water the better.
*Replace the stock radiator with an all-metal version. Usually those are larger capacity. Fluidyne and Koyo are two popular brands. Fluidyne is about 1.5 times larger, Koyo is 2 times larger. But the larger you go the more fitment issues are typical and doesn't automatically mean your car will run cooler the larger you go.
*Replace the stock plastic AST with a metal version.
*Replace BOTH caps.
*Closely inspect all coolant hoses and replace if any are leaking or swollen. Particular attention to the turbo coolant hoses.
*The stock thermoswtich activates the fans at 108 C. (225 F.) Many owners replace it with the Series 5 FC thermoswitch which activates the fans at 95 C.(203 F.) ...much sooner. It's a complete "plug-n-play' replacement for the stock one, but a little work to get to. You'll have to remove the alternator and a few other things to access it. It's very worthwhile though given that seal damage can start at anything over about 240 F. Read the stickys and search in the 3rd Gen. section for more threads and information. And download a copy of the FSM (Factory Service Manual).
*Get some upholstery foam and plug any gaps around your radiator and A/C condensor.

No, you can't just buy another stock oil cooler. There is a left and right side. Typically you have to buy the dual set from an R series which will come with lines and ducts.

ONLY after you do the above would I worry about the stock IC. It doesn't make your engine run cooler.
When you get your post count up, there is a Parts for Sale section for the 3rd Gen. car which can be a great source for used parts.
It's great your thinking first about cooling. Many new owners don't and pay the price down the road.

Sgtblue

iTrader: (16)

Correction: If you don't already have it, you also need a boost gauge. Water temp and Boost. On a stock car others are either redundant or silly.

joel_rx7

iTrader: (7)

Hello,

Yes you can make a second oil cooler yourself using a spare driver's side oil cooler, take a look at a post named "dual oil coolers cheap" from Howard Coleman. I personally bought a used one from Japan (there are as few vendors that will get it used from Japan for ~$100 in a very good state).

I personally put a Koyo and water temps are steady and not to hot when spirited driving. I also hit the track for the first time this week but since it was raining it wasn't the worst condition. I think that if you do all of the reliability mods that are in the FAQ it will be good enough for stock level power.

I can't stress the need of having water temp and boost gauge enough and also check the cooling fan operation. You can have the biggest rad of the world but it will be next to useless when you come to a stop after spirited driving.

Sgtblue

iTrader: (16)

---> https://www.rx7club.com/showthread.p...&highlight=oil
Parts list on page 1. Pictures on page 3.
I think you should be familiar with the car and have at least passing fab skills. That's why I didn't recommend it above. For what I've seen stock R series dual oil coolers go for (not much more than the parts cost in that thread) it's not worth the trouble IMO.

rseamon

The reason why the guages are so important is because you need to know where the weaknesses are in the car. Does it run hot, does it run lean, do the turbos work correctly. These cars are very old now so doing so called reliability upgrades can have deleterious effects. Upgrading your intercooler can easily make you run lean. One oil cooler may be fine for the way you drive, maybe an oil temp guage will tell you. More important are your oil lines intact, is your fuel system intact, vacuum hoses intact, all lines intact, turbos working properly. You dont want to stick on a downpipe or an intake or an intercooler till all the basics are inspected and guages are installed. Make sure the three main recalls were done. Bottom line is dont attempt to upgrade a car till all the basics are covered. Reliability upgrades from ten years ago are not the same today, some of these post are many years old before vacuum hoses issues and fuel leaks were the norm.

gracer7-rx7

iTrader: (16)

You can but it shouldn't be your first priority. The single oil cooler is totally fine for street driving.



The stock radiator is enough to cool the stock car. Problem is that all the stock radiators are worn out at this point and the plastic is ready to crack. That is the real reason to replace them.

I suggest replacing with the Fluidyne radiator. It doesn't have the fitment issues of the Koyo and it is more than enough to cool a car with major mods.

Cooling system first. Intercooler does little for you at stock power levels. Don't do a FMIC - that will compromise engine cooling. V mount won't fit your college budget so skip it.


You're kidding me right? Did you read the 3rd gen FAQ stickied in this forum?

rseamon answered that question for you. Although his comment on the intercooler causing the car to run lean is not correct.


SgtBlue's responses are spot on.

qkaqk

iTrader: (1)

Thank you for great info.

My FD already have done with Defi Boost and Water Temp gages, and also

I'm not sure about it but my AST isn't a plastic piece (I just hit the finger and guessing).

I don't think I'll go track for next couple years.

But I had some heating issue when I idle for little long time or

stuck in traffic. (even hit 235 F when I hang around to find parking space)

It has 51k miles so far.

*Summary for current FD
-51k miles
-Defi Boost and Water temp gauges
-aluminum outgoing intercooler pipe
-Not a plastic AST


EXTRA QUESTIONS
-my FD doesn't consume oil, is it fine?
(I check every 5~700 miles and didn't consume at all for 2k miles)

-It's happen randomly that when I drive little long time (like more than couple hours) car has jurky motion under 3k rpm or -10 psi. I don't why why happen randomly, so hard to check.

-Can I use stock Bose system with aftermarket head unit?
(It didn't work since I got it, and aftermarket head unit had installed when I got)

Sgtblue

iTrader: (16)

235 F. is pretty high, especially given what ambient temperatures probably are in Delaware right now. You still have cooling issues. When summer comes it will get even worse. Your engine is at risk.
Go through the list of things mentioned above. Just internet guessing, but you might check that the face of your radiator isn't dirty/clogged (just behind the AC condensor). If cleaning that doesn't help, check that your fans are working at all speeds.

Oil consumption not showing on the dipstick in that few miles isn't a concern IMO. It could be camoflaged by a little fuel dilution, which is also typical of a rotary. That's one reason why most of us recommend oil change intervals a little sooner than piston engines.

Thankfully I never had to mess with the BOSE system, but from what I understand, the speakers are individually amp'd and you can't use them with a standard aftermarket head-unit.

Sgtblue

iTrader: (16)

I disagree. A new FD owner ignores the time tested basic reliability mods spoken about 10 years ago at his/her peril. And if "fuel leaks" are the norm it's news to me. I've had my car nearly 10 yrs and never had one.
If the car is absolutely show-room original (recalls and TSBs aside)....in no particular order:
*Replace pre-cat with a downpipe.
*Replace OEM rubber vac hoses with quality silicone
*Replace OEM plastic AST with a metal version
*Replace OEM radiator with plastic end-tanks with all metal version...usually larger
*Replace OEM rubber 'Y' pipe/crossover coupler with a quality silicone version
*Miata...now S5 FC thermoswitch for the OEM version
*Fan mod
*Clean OEM grounds and add supplementals (battery to engine, battery to chassis, chassis to engine).

Every one of those reliability mods is still valid for a near original stock car. Changing the intercooler isn't one of them, that's a performance mod.

rseamon

He may disagree but I am by no means am I a new owner, my car is a 93 and I am the original owner. Yes many of these cars leaked gas and had fires. My car had bad injector gaskets and a leak in a fuel line. Main injectors were running at about 75%. You stick a downpipe in the equation and detonation is highly possible even though its a "reliability" modification. I understand that your car is running hot and yes a downpipe will keep it cooler but you need to find out what is making your car run hot. Which goes back to what I said before, go back to basics and make sure everything is working properly before making any new changes. You add a downpipe you run more of a risk of running lean and possibly turbo creep. New problems before the old ones are fixed is no fun.

Sgtblue

iTrader: (16)

I respect that, and appreciate your willingness to help, but your experience isn't common.
No, they didn't. There were a few and usually catastrophic. And for obvious reasons they garnered attention. But IF a FD had a fuel leak it was typically traced to the Fuel Pulsation Dampner (FPD). Others were traced to neglected turbo coolant lines. If you get coolant hot enough, it burns. But unless you neglected these (FPD and turbo coolant lines) or (in your case) the fuel lines, fuel leaks were NOT common place. I'd bet the vast majority of owners have never experienced a fuel leak.
With injectors only flowing 75% of their potential, running lean is likely regardless of ANY modifications.
A downpipe reduces underhood temps, but practically NOTHING to help the engine itself run any cooler. It's a reliablity mod because the stock pre-cat that it replaces was prone to collapsing, plugging and destroying the main cat and ruining the engine. It will reduce backpressure, but has little risk beyond that. It is one of the FIRST mods anyone who has a completely stock car with a precat should perform IMO.
Nope. Boost creep is caused from too little backpressure and the exhaust overwhelms the stock wastegate. But by itself, replacing the pre-cat with a downpipe WILL NOT CAUSE CREEP. Typically creep will only occur if you remove the main cat ala "midpipe" with a free flowing catback replacing the stock cat-back. Even then not all owners have the issue. If the OP still has a pre-cat he needs to remove it. Your giving bad advice IMO.

rseamon

Ok I will attempt this one more time. You got a guy who has limited funds in college. First he wanted to add an oil cooler because his car is running hot, then an inetrcooler for whatever reason or advice. Then he tells of a fuel smell. This is the guy who tapped on his AST to see if its plastic!!Running hot, possibly lean and has no clue what he has under the hood and has upgrade fever. My advice...get your car fixed, I have driven in some pretty hot temps and never run hot, fuel leak...find it and fix it, find a good mechanic in your area through this forum etc..Make sure you know all the modifications done on the car before you. Then if you have any money left start thinking about reliability mods and assessing your car. Are both turbos working properly, are you running lean, good compression, fluid on the garage floor, hose inspection etc..Getting rid of the precat is a good idea as long as your state does not do an underhood inspection and you know it can be illegal. Most of the experienced guys recommend no mods till your car is running 100% because its always possible that a mod can lead to a new problem, usually because of a preexisting problem unnoticed. Why I say the old mods are outdated is because they dont talk so much about the rats nest and hoses because back then they were not so much and issue. Now they are a problem and difficult to detect. Directing funds towards that is not a bad idea even though its not all that exciting.Then if you have money left think about the exciting stuff and there are all kinds of different opinions as to what are the priorities for reliability mods most usually leaning towards exhaust ie downpipe and catback.

qkaqk

iTrader: (1)

Thank you again for answers

I'll check everything fine on your list.

Also, emission test will be fine with pre-cat and downpipe?

*I checked my radiator; it doesn't have name on it, but it has metal(or aluminum)head. I think it already had replaced.

qkaqk

iTrader: (1)

---------------------------------------------------------------------------------------------------
Thank you for info again.
I've just gotten my FD few months ago, and
I don't know who is the previous owner.
Friend of mine who is car dealer bought for me from dealer auction,
so I don't know what modification has already done.
I checked basic inspection from shop near of my home (I know now I should have chekced at rotary special shop)

However, I didn't say that I could smell fuel or any have fuel leak.
(It's leak free and smell nothing expect nice leather smell)
Because of high temperature in low rpm (and idle too), I checked
basic cooling inspection, that same as other cars like radiator fans, circulation, and any leaking, was fine everything.
I though my stock part need to replace by age or because IT'S A STOCK.
I've read many thread here before I got my FD about things that I should checke and should replce.
Most of I read about heating problem, so I guessed I definately need to replace stock cooling system.
That's all.

Thank you again, and I'll go see rotary specialist to get whole inspection.

rseamon

Sorry about that someone else pointed that out to me as well. I got PM ed and thought it was you. My opinion has always been not to modify till all problems are fixed but some of the other guys have disagreed with me and feel some basic mods like a downpipe may save your car if you plan on driving it while still having issues, so definately review all the opinions that were presented to you and discuss them with the Mechanic you find. Good luck.