Why do 1st Gens run so long? (and 2nd and 3rd gens die?)
 

A couple of years ago I posted a poll on the number of miles on 1st gens. Results are that 55% of those who voted have over 100K on the original engine (28% were over 150K). I find this data amazing!

(original poll: https://www.rx7club.com/showthread.p...2&page=1&pp=15)


Anyhow, I am wondering why do 1st Gens run so long -- especially in comparison to 2nd and 3rd gens, which seem to die early. Virtually every 3rd gen on ebay or AutoTrader has a new engine (unless it is a garage queen). This seems frequent on 2nd gens as well.

Someone told me that the injection system on 1st gens are more robust, and that Mazda cheaped out on the later versions, making them less reliable. True?

most of the places i read rate the 12a engine for 100,000miles.................but on here people have them going strong way past that! I guess we just know how to drive them in just the right way.

Older engines can, in many cases, be stronger and more solid. thats probably why, but who r they rated @ 100,000 then.

plus the 2nd and 3rd hav boost, and most of them pop because of improper modifying.

Edit: in addition, the 1st gens usuallyt have older, and more mature owners.

The complexity of the 2nd and 3rd gen engines got so much more complicated. I was looking at a friends 2nd gen haynes manual and i was overwhelmed with the tons of sensors. The engine has a freaking sensor for just about everything. It makes me think i like my engine much more for the freakin simplicity!

Yeah, it seems the average life is 50K more miles than 2nd gens. What I noticed with 1st gens for sale in my area is they hardly had any rebuilt engines. While there is a greater number of 2nd gens that have had rebuilts.

This is why the SE was released with a 13B fuel injected engine instead of the Jspec 12A Turbo - reliability. Mazda hadn't yet learned how to make a turbo rotary last, and knew it.

my fb had 239k on her befor she blew...:( and now i wait for my "new" motor to get here... and have been over a month... :( my girl has an 81 that has 135k on her and she runs great!

Mine has, let's see, 189 k or so? The carb quit before the engine did @+@

First gens rule! Just got back from a 2600 Km trip over 4 days! never missed a beat! ran flawlessly! 13B 6 port EFI.!

I am quite pleased with my 1st gen. Very glad I got it instead of a z32, or the FC I was looking at.

Only part I hate is I have to check the weather forecast, if its raining my toolbox has to go in the back so I do not spin around on the highway in a turn. Yes it has happened.

If it spins that easily, you may want to look into some better tires. :)


Do the FCs really die that quick? I know the TIIs don't last as long, and obviously the FDs are pretty stressed, but I thought the NA FCs were good for 150k+ miles (which may not be as long as an FB, but long enough that I wouldn't say they die early).

They are new tires. :(

I've noticed that as well. Most FB's still run on the original engine assuming it's taken care of.

I'm suprised you can get yours to spin so easily, I've always thought my 7 was the best in turns out of all the cars I've ever had including a Z28. I have to really be trying to get mine to give loose.

In my car, in wet weather or sand, i cant help but go sideways and do burnouts. Its just too fun:D Dry weather is great though for going fast on the highway on/off ramps(those are like the only good turns around here)

I always heard that it was because the 13B had replaced the 12A in production for the late model year of the second gen rx. Also werent the 12A rotary turbos in Japan pretty reliable when they werent toyed with???

i hate to admit this, but the past 5k i havent been premixing (which i know if really bad and i have been the last 2 fill ups) and i have BEAT THE SHIT out of my car for the last 30k miles (autox, drag, 'spirited driving'), and i rolled over 160k last week.

and people told me not to get an rx7 because they are 'unreliable'.. yea right. my friend had the CLEANEST t2 ive ever seen with 50k on it. he upped the boost with intake/exhaust, but no fuel and literally blew the motor in 20 minutes. i know that was his fault, but still.

i love my first gen man, and i wont blame it when the motor pops, but she hasnt failed me yet (knock on wood)

Yeah people always tell me, don't blow an apex seal going to the store. Fucking jerks, if they only knew the power of the rotary.

yea with my girls fb i have to try pretty hard to get sidways but mine just slides right out... the lsd makes a huge differnce

Our cars are more reliable because most of us don't have boost. Anytime you add that to the equation, your reliability drops down considerably. Plus a lot of people up the boost w/o fuel. 2nd gen NA's are just as reliable as 1st gens. IMO, 1st gens are built a little bit stronger (ie suspension, interior...etc)

I ran mine Til 138 000km
only a Week ago, lost a seal on the express, But my 85 gsl se has had a Cartech Turbo for at least the last 15yrs!!!!!!

If your former statement were true, they wouldn't have put 12A rotaries in every model of Series 3 (1984-1985) RX-7 except the GSL-SE.

For the record, my daily driver only has 171k on the original engine... and still rolling along. I might hold off on the P-port until this engine passes 200k. :D Should get there by roughly November of next year, but I don't know if I can wait that long.

2nd-gen N/As also last a long time. Their 2mm seals are also much easier on the housings, you can take a worn out FC engine and it's rather likely that the rotor housings are still useable.

The Turbo engines, though, burn their candles at both ends (twice as bright but half as long)

Mine just clocked out today at 162k miles. :(

from what a friend of mine told me...mazda went to smaller lighter apex seals on the newer cars...which were susposed to cut down on friction...but lowwerd the life of the engine...which they didn t find out untill it was too late

There seem to be a lot of opinions and theories about this subject, but one fact is indisputable, according to several people I know who make their living working on Mazda rotaries: The 84-85 GSL-SE is the longest life rotary ever built. Some will run 250,000 miles. In my opinion, the explanation is simple - this was the first engine Mazda built with direct oil injection into the chambers, and the last engine they built with the 3 mm apex seals. Previous engines were all carbureted, and the oil was fed into the carb. The 86 and later engines also have the direct oil injection, but they have the 2 mm apex seals, which are just not as durable. Several rebuiders I know will machine out the later rotors for the 3 mm seals if they want to build a bulletproof motor.

As for the 3rd gen cars, the specific output ( as in horsepower per cubic inch) is just too high for long life in a rotary, using current technology.

I was a big fan of the rotaties for 20 years, did rotary engine transplants, built ported engines, etc. But I think the time of the rotary has come and gone. The new technology piston engines with the variable valve timing, and even variable lift, and all the other optimization, combined with turbocharging, has allowed the piston engines IN MASS PRODUCED FORM to outperform the rotary and still get much better fuel mileage. If you don't recognize this you just aren't paying attention to the technology. It is very unlikely the rotary will ever close that gap.

I'd have to agree with that statement, BUT not American cars.

Why not? The chevy cavalier/pontiac sunfire motors have vvt, and do 140-160hp with around 30-35mpg. The ford focus almost gets 30mpg at about the same hp, and the neons too.

overstock perhaps??? maybe youre right, i will look into this...

I'm not sure if I agree. Porting and intake advancements have already made enormous progress in shape of the Renesis. And they have done all this on the same 13B platform. If Mazda ever switches to a new rotor size, housing, and chamber design, we could see equally large advancements. And at the rate they have been going on (without full support of Mazda I might add) the engineers are personally devoted to making things like this happen. It was their off the clock work that made the Renesis and eventually the RX-8 even happen. Now that Mazda sees it may still be profitable, all they need to do is exploit the rotary again, put it into several vehicles, and reap the profits for further advancements. Yes the piston engine will keep advancing, but the rate of that advancement will slow because once they reach that percentage which is as close to close 100% efficiency as is possible, the rotary can only catch up.

84SE Daily Driver with 179k miles on it - still runs very strong but a bit of smoke on cold-start (MMO in the oil - don't do it...).

80LS Daily Driver (before the SE) with 212k miles on it - SCCA weekends, young driving habits, and blown out oil cooler hose were the causes for it's overheat and eventual slow death (from overheat to dead and non-running in 30 minutes/10 miles).

Take care of it, and it will take care of you,

aboiuyt 220K miles on my old engine.. untill the radiator shat itsself....

she still went strong!

stilettoman...have you ever driven a sunfire or a cavaler? they are shit that have shit engines that redline too soon...and crap out too fast. the only companies that make engines that are comparable to rotaries are the italians and the germans... I would say a high revving small displacement V12 is simmilar in ethos to a rotary...not a big displacenemt american peice of scrap iron.

the rotary is more efficent and a more advanced design...go read about felix wankel and his first rotaries...

Long live the rotary

I agree
 

To think that a motor with pistons is far superior than a motor that is not put in every single car is closed minded, there has been quite a few motor companies that looked into making the cars they make Rotary powered, Mazda was the only one that could make it work and thru R&D have come a LOOOOOOOONG way from the original design. Im SURE if more people were to show interest<aka money> into making a reliable, emission friendly rotary it could happen. Untill then to hell with the Earth, I wanna blow flames!!!

They began building the GSL-SE in 1983 as a 1984 car. You're saying that they had enough hand assembled 12As in 'overstock' to put them in every RX-7 except GSL-SEs (S, GS, & GSL models) for two and a half years?

[QUOTE Anyhow, I am wondering why do 1st Gens run so long -- especially in comparison to 2nd and 3rd gens, which seem to die early. Virtually every 3rd gen on ebay or AutoTrader has a new engine (unless it is a garage queen).
QUOTE]


Because First Gens rock! :bigthumb: :D ;) :cool:

Modifying or Not the Turbos have alot more stress and heat on the internals. If its weak it runs forever. And all the first gen owners ive seen are in the 500 dollar club. i.e. highschool kids. or chumps with no money. I dont see how that equates to Older mature owners.

Let's see... off the top of my head there's DirectFreak, Tom, and myself in the out-of-high-school-and-making-decent-coin crowd...

There are a lot more of us 'enthusiasts' over 30 than you'd think. These cars can't be relegated to the 'high-schooler' crowd anymore. True that a lot of us first owned these cars in highschool, but that was back in 1989 when I graduated, and I owned an 80LS for most of that time.

Maybe it's that the 1st Gen enthusiasts here take better care of their cars knowing that they're 20 years old and require a bit more TLC than some of the 2nd Gen and 3rd Gen cars. JMTC,

I guess I'm in that "highschool" crowd, bought mine just before I turned 16 and I'm 18 now and just got out of highschool. I coulda left my car stock and drove it forever, it was a really fun car. But I wanted more power, so I put a turbo on the 12a. And now about 1.5 years after I first went turbo I'm finally getting it right :)

I'm not in high school so I must be a chump. :p: Thanks. Some of us bought first gens new, and then bought second and third gens new as well. I'm not sure where you are seeing your first gen owners, but in my part of the country it is the opposite situation. The "kids" are all third gen owners (sometimes even scrimping on food to save money for their cars). There are not many first gen RX-7's around at all, and those who have them are generally older than the most of the other generation's owners.

Seems to me it is more often the younger kids doing the most modifications, and usually to third gen cars. All of the RX-7 models are relatively inexpensive, and none requires huge sums of cash to own or modify. The value for the money is one of their best features.

I am 20, married, in the Marine Corps, have been to war, and have a one year old son. I don't consider myself to be in high school, but I am sort of a chump. By the way i am in the 100 dollar club. :)

My Rx7 has 102k miles on now.When i bought it,it had a streetport allready (so it was open at least once previously) with 95k miles.The people aroung here just dont treat the Rotaries proper.
As we dont have more than 5 Fc`s and Fd`s here,i cant say acurately which lasts longer.

I think Mazda should have installed a rev limter on the FB,to stop mind-less people from destroying all the nice Rotaries here.Its one of those things here,they dont last long.they get abused too much.


Sounds depressing?Nope,we have a few that are in mint condition as well.Last week there was a `79 for sale,with +- 43k miles on!!!! :-)

Karis

Its not really the high school kids either. I had two cars restored while in high school. I worked my ass off to pay for it. The only help I received was from my dad, and he provided labor or advice. And all the nice tools, damn former aircraft mechanic. Has more tools than any automotive mechanic. Using a scope to look for rust in the body was cool though. :)

You need to meet more 1st gen owners.

Am I cheap? I like to call it frugal. Chump? NO WAY!

I turned 16, and got my license, when Mazda released the 1984 GSL-SE. I was in love.

It took me 20 years before I got my 85 GSL-SE. Married, 3 kids, and my other car is a mini-van (soon to be Suburban). So I would put myself in the mature and budget-minded. :cool:

Roger

Chumps with no money? :rlaugh: :rlaugh: Perfect example of stereotyping :rlaugh: :rlaugh:
I love my 1st Gen!! My GSL SE is paid for, brand new, off the show room floor about 20 years ago yesterday and still in awesome shape. I think it's safe to say for the 1st Gen owners that their cars are paid for.
I make $125K a year :bigthumb: , so I don't think it's a poor man's car ;) :D :rlaugh: :rlaugh:

Oh and BTW, I'm 40 :cool:

Yeah he got it completely backwards. It was kind of a strange comment to make.

Dang, what do you do? SOunds like i need to get a job where you work.

I think many 1st gen owners are frugle. But they are a decent # of us here that can afford a newer car but choose to restore/revamp our 1st gens. :bigthumb:

well i can't afford to have a brand new car, but i could afford to have a nice late 90's model vehicle, but i choose to own multiple rx-7's instead, its keeps a big old grin on my face!

i thinik the reason younger kids like myself love these cars so much is that not only can we afford to own them, but we can afford to mod them. Really i think that 1st gen owners are lumped into two groups, the young kids, and the older ones who grew up loving the car either wanting or owning one. And now its really easy and cheap to own them again. Thats the way my dad is, he bought one of the showroom floor in 1980, and has loved them ever since, so when he got the chance to pick a good one up for cheap a few years ago he jumped on it. And that in turn got me hooked!

id have to say the reason 1st gens are so reliable, along with 2nd gen N/A's is obviously the lack of boost,