Buying an Rx-7

Intro:
I have been getting a lot of requests for advice regarding the purchase of used Rx-7s. For this reason and in order to have a more complete web site I have decided to add this section. If you have already bought an Rx-7 this page won't help you much. If you're a new owner check out my new section called New Owner (not yet created) for info on maintaining your car and getting involved in the Rx-7 community. If you are thinking of buying an Rx-7 read on.

Comparisons:
I get a lot of questions regarding how well the 3rd gen. Rx-7 compares to other cars. This is normally divided in to two separate questions. Performance and reliability.

A) Performance:
First of all let me point out that you simply can NOT compare this car to the likes of Honda Civics, Accords and all other non-high-performance cars! To get a sport coupe up to the same level as even a stock Rx-7 is a monumental task. If you desire a high-performance car, start with a good platform. If you don't have a lot of money... well I didn't either when I saved for countless years to buy this car. Just don't waste your money on a heap of Honda junk.
Now then, what about the other high-performance cars that are available for around the same price as an Rx-7. These include the likes of the 300ZX TT, Supra, Corvette, 3000 GT, and a few others that are more obscure. Well these are all pretty good cars except for the 3000 GT. It's pretty much a hunk of junk with it's poor suspension and heavy weight. The other cars are very respectable in their own right and can be made to very fast cars just as the Rx-7 can be. The biggest difference is in what you plan on doing with the car. If you want raw power that provides for low 1/4 mile times then take a look at the 7's arch rival, the Supra. This is a very respectable car but does have one flaw. Weight. In fact all of these cars pail in comparison to the Rx-7 in this department. This flaw can easily be overcome in the 1/4 with added power and sticky tires but on a real race track it's a different story. Supra owners will point out that their car achieves a similar skid pad rating as an Rx-7 and this is true but this is a factor of traction, down force and weight. Given enough of the first two weight can be overcome. However in things like slaloms and Ss where the vehicle's weight is transferred from side to side, a lighter car is always better. It has been proven time and time again that Rx-7s are superior to other cars at places like autoXs and real race tracks. Just take a look at articles like SCC's article, the g-force challenge. The Rx-7 was called a ringer by the other publications but it was practically stock compared to the two Supras. The Supras had huge turbos and lots of suspension upgrades. The Rx-7 also had similar suspension upgrades like shocks and sway bars but it's power upgrades were minor. Needless to say the Rx-7 was untouchable.

B) Reliability:
There have always been questions of reliability regarding the Rx-7 and some of these concerns are well founded. Many of these concerns revolve around the car's twin sequential turbo system and of course the rotary engine. The sequential system is designed to virtually eliminate turbo lag but is very complex with its many vacuum hoses and solenoids. The turbos themselves are pretty solid but trouble shooting a boost problem can be very frustrating. Upgrading to silicone vacuum hoses can prevent failure to a large extent but problems can still happen. If you aren't knowledgeable enough to diagnose the problem yourself then you must find a reputable Rx-7 tuner. Many 'O' Rx-7 turbos have been replaced because the techs were unable to diagnose that the problem was in a $40 solenoid. This brings me to my point about the cars reputation being created in part by poorly trained techs. A lot of replaced parts on Rx-7s have been replaced because Mazda dealer mechanics are unable to find the real problems. There is however the main reliability concern, the rotary engine. This is both one of the major problems with the car as well as one of the reasons it's so good but that will be discussed later. There are two points of failure with a rotary engine.

1) Apex seals. These are basically little shims located at the corners of the rotor (spinning triangle). They are delicate and simply can not withstand even minor detonation (also called knock or ping). There are three main reasons these seals fail from detonation. One is luck. A dreaded thing that has always had great meaning in my life for it is beyond one's control and influences everything from finding the love of your life to crossing paths with a dreaded mini van driver. I have seen guys with very well maintained Rx-7s with low miles that lose their engine for apparently no reason at all. It could always be a bad tank of gas or a flake of carbon but it's really hard to find reasons sometimes. The second reason is that over time the apex seals wear down and become weak. This has less to do with detonation as it does with the seal simply failing but if detonation does occur it won't take as much with worn seals. This can be prevented by replacing them when you notice certain symptoms but expect to pay nearly as much for a rebuild as you would for a new engine. (This is about $2-3K + $1-3K for install.) Checking for worn seals will be covered later. Lastly and perhaps most common is poor tuning. This was particularly a problem when the car first came out because tuning a Rx-7 is much different from other cars. You can't just up the boost and throw on a few upgrades like you can with other cars like the Supra. One of the reasons for this is because the car doesn't use a MAS (Mass Airflow Sensor) so if you increase flow the car doesn't adapt as well. Another reason is that the computer isn't flexible. This has resulted in a great many poorly tuned Rx-7s that blow engines. Although this isn't the fault of a design flaw, it has been a heavy contributor to the poor reputation of the rotary engine.

2) Coolant seals. The rotary engine is very susceptible to damage from overheating because if it happens the rotor housing will warp, which exposes the coolant seals to the combustion chamber. There are made of a rubber compound of some sort that simply can't withstand fire. They quickly fail thus allowing air in to the coolant system when the car is running and coolant in to the engine when the car is off. As the problem progresses the car will require constant looking after to make sure coolant isn't replaced by air and when the problem gets really bad it will become nearly impossible to start due to water sitting in the engine. There are two reasons Rx-7s over heat. One is that the cooling system isn't adequate especially for modified Rx-7s. Second is because the stock temp gauge is an idiot light, which moves in to the high zone only after it's too late. Many owners ignore warnings from those like me and don't bother investing in a simple after market temp gauge. If you can notice that you're starting to run hot for whatever reason the damage that will result can be easily avoided by pulling over.

So what does all of this stuff boil down to? Well the rotary engine has been known to last well over 100K miles. I have even heard rumors of 200+K miles. However 80K seems to be when problems can be expected. Much of it depends on how you drive and your mods but truth is that many owners consider replacing the engine as inevitable. You have to remember that this is a super high-performance car though and all cars like it will need parts replaced that are under so much stress. Personally I have gotten away with very low maintenance costs. There are of course other problems with Rx-7s like bushings and engine mounts but all cars have their weak points. There are upgrades you can do to eliminate most of the weak points but if you don't want to worry about such things then you probably shouldn't be looking in to high-performance cars.

For more on comparisons take a look at my Rx-7 vs. Others article.

About You:
Simply put the Rx-7 is both technically involved and different. You can't just take it to your local Jiffy Lube for an oil change or even your local Mazda dealer for service. If you do, expect trouble. For these reasons the Rx-7 requires a certain type of owner. One that is border line obsessed and has a great thirst for learning about their car. You are reading this though so you may have already passed this test because only this type of person would bother to visit my site. There is more though. You need to be very detail orientated and be willing to do extreme things to keep the car running right. Things like driving it 300 miles to the closest Rx-7 tuner and learning how to do work on it yourself. I have talked to a great many guys that were destined for failure. They buy the car because they think it's fast or because the saw it on The Fast and the Furious. They normally inherit somebody's problems and lack the devotion and skill to fix them. Ownership usually lasts less than a year. However if you are the right type of person expect a great level of satisfaction. There are those who take one drive in an Rx-7 and never want to drive anything else. I have even talked to rich guys that have owned dozens of sports cars and have sold most of them once they become boring but for some mysterious reason they keep their Rx-7s. The Rx-7 was designed from the ground up as a pure sports car that connects the driver to the road. Light weight, excellent suspension, sequential turbos, lots of power, and an engine that's unlike any other make for a driving experience that has rarely been captured. Magazines still name it as one of the best production sports cars ever made and for the money I'm 100% sure it is the best. If this sounds like something that will capture you then read on.

Differences Between Years:
This has always been a big debate among owners of Rx-7s. Many seem to think that because early 93s had problems that all 93 Rx-7s should be avoided. Truth is that these "problems" shouldn't be much of a concern. The problems are defined by 3 main recalls and various things on the TSB (Technical Service Bulletin) list. All recalls should have been performed on any car you look at and if not don't worry because it's easy to check and have them done for free. TSBs are often minor and when they aren't like paint chipping you will either notice it or a previous owner will have dealt with it already. However avoiding early 93s (built in 1992) can be advantageous but things like mileage, price and general condition of such a rare, old and often abused car should be of more concern. In regards to changes other than TSB fixes the 1994+ years got softer suspension and PS airbags. These changes added a bit of weight but basically the car is the same.

Looking at Cars:
A general rule to buying a used car is to have it checked out by a qualified mechanic before spending thousands on what could be a car on its last leg. This is even more important for Rx-7s. If possible take it yourself to a reputable Rotary tuner but if not at the very least have the owner take it to a dealer. Just make sure it's not a basic inspection but a comprehensive one. Talk with the dealer yourself and ask for various problem areas to be inspected. You can still buy the car if there are problems but at least you will know what you're in for and might even be able to get the price reduced.

Here is a list of problem areas:

If you're unable to have it checked out or are just too lazy, doing a car fax is a good idea. Also when you go to look at the car and drive it look for normal boost and a smooth idle. Neither one means you shouldn't buy but combine these things with other things you notice like does the owner have good records, why is he or she selling, and the general condition of the car then you might have good reason to pass on buying. Before the test drive remove the filler cap for the coolant. It should be topped off or very close to it. If not fill it and turn on the engine with the cap off. If you see small bubbles rising to the surface it means the coolant seals are going bad. After the test drive turn the car off. Look for oil leaks, smell for coolant and then have the owner turn it back on. Watch for a puff of white smoke out the exhaust. This will indicate coolant seal failure as well. If the car is hard to start when warm it could indicate worn apex seals. If the engine is hard to start when cold, well that's not good is it? Reasons will vary for this. Since you aren't yet an owner there is only so much you can try to find but just use your head and trust your instincts.

Final Thoughts:
Buying a car of this magnitude shouldn't be taken lightly. It's complex and isn't as easily fixed and maintained as other cars. You will need to learn the differences between this car and normal cars because although different doesn't mean harder or more costly it does mean conventional knowledge won't apply. Even veterans of import tuning are often baffled about the Rx-7. Be warned that these people still sometimes think they know a thing or two so be careful what advice you listen to particularly in regards to tuning. There are several factors on your side though. For example due to the passion the Rx-7 invokes many owners are very devoted and are willing to help other owners. The Rx-7 community is very strong and owners are among the most loyal to their cars and each other. Getting involved is very important. I know if I hadn't joined my local club I'd be only 1/2 as knowledgeable as I am and would be paying much more for repairs. Lastly I always enjoy hearing from you and will do my best to answer your questions. If I didn't answer something here or if you just want to get my thoughts on something feel free to e-mail me.

Buy one and take it Home