Mine had 101,500 miles and was still running. I just pulled it due to the oil pan leaking like no tomorrow.

Adam

 

I customize all my vehicles to drive and feel a certain way. I like a deep tone exhaust that's just audible in the car but not in my neighbors home. I like a tall first gear, close range gearbox. I love the feel and the simplisiry of a single turbo.

No matter how bad u want to believe the rx7 is a modern marvel it's not. Its a simple engine and It's at it's best when it's in it's simplest form. A good hi tech car is the GTR and that's what I would buy in that price range.

Top gear compared the caterham 7 to the Bugatti veyron. On the race track the low tech caterham was faster. We all know the rotary can make big reliable power if tuned properly and being so light it can maintain balance in a small car. That is the strength of the rx7. It can beat all the compition and cost far less to produce.

If its well engineered it won't cost a lot and mazda can build options to meet everyone's needs.

 

In all seriousness the head guy behind the Rx7 resurrection stated that he prefers the rotary to stay NA. If that's the case upgrading the power is gonna be seriously limited if they ONLY build the 16x version. The Rx8 guys had hell trying to get more out of the Renesis. That being said, Mazda would be stupid not to offer a 3 rotor version if their goal is to stay NA. A 3 rotor isn't that much more expensive since the majority of the parts will already exist with the 16x. If the chassis is developed with a 3 rotor design in mind (like what they did with the Cosmo" then I see no reason not to offer it as a TRUE Mazdaspeed version. If the 16x is capable of 300hp, then the 3 rotor version could easily hit 450hp. I don't think anyone will complain about that version NOT having enough power to compete with whatever's out in the market.

 

Keep the wisdom coming, I'm really learning heaps from your posts

 

This is so unrealistic I don't even know where to begin.

 

Why? That's where the market/industry is. 240hp isn't going to cut it anymore. And there are $50k Hyundais out there.

 

An NA 3 rotor wouldn't have the heat or complexity issues of the 13b but could still rev high and possess a great power band
It really seems like a no-brainer (which isn't to say that they'll do it lol )
A 3 rotor is still a relatively compact/light engine and can be placed low in the chassis - it would be great for maintaining the lightness and agility that they should be striving for

When it comes down to it, I believe all the tech already exists, it's just a matter of proper packaging

 

the 3 rotor does have complexity issues, it also needs more cooling than a 13B, and the big killer, is gas mileage... plus its heavier, bigger etc.

these reasons are basically why we didn't get a 3 rotor in 1989, and why they didn't use it in the FD, and why you're not going to see one now.

i had a 3 rotor in an FC from 2001 to 2004, the sound and power are awesome, but its just not practical

 

so you select cars based on the weight of the transmission? that is an interesting approach. i admit i do avoid cars for this reason, AWD Audi's spring to mind...

 

I can't imagine an N/A three rotor requires more cooling or is any heavier than a turbo two rotor—at least when you factor in the turbo, ancilaries, intercooler, control system, etc.

I'm not even sure overall gas mileage would be worse, since you won't be running turbo AFRs under boost.

Might be better at idle. It would be cool if Mazda could figure out a way to shut down rotors/firing cycles like they do with piston motors to help out the emissions/mileage at low rpm/load.

 

Next RX needs to be "small" and lightweight. The biggest change in the past 20 years of automotive building is the resurgence of SIZE. Ever park you FD next to a new Camero or Challenger (see pic below)? Talk about BLOAT. No wonder they need to have 600 HP and 550 FT-LBs of torque to get them motivated. I was really surprised a few weeks back when I parked my FD next to the new FRS. Now, granted mine is lowered, but still, the FRS is a bigger car. I also was amazed when the RX-8 came out that it weighed less than 3000 lb. An incredible feat (IMO) for a car with that large of a footprint. Mazda needs to do the same with the next 2 seat rotary sports car. Similar in size to the FD and 2500-2700 lbs with 350 hp and we'll have a winner!

 

^^^

Indeed. Park it next to a 350/370Z for that matter.

 

"Next RX needs to be "small" and lightweight."

absolutely.

next to the Lotus of old Mazda stands tall in the lightweight category. you probably have heard the FD story...

Mazda had two teams that had as a sole objective taking weight out of the FD. they couldn't talk to each other and worked for almost a year on their project. that explains the swiss cheese swaybar mounts.

pass the cheese.

howard

 

The FD has always been sized fine for me even though I'm now a little chubby for 5'8". But what's the demographics for a "small" car? How small? I see alot of posts from guys having difficulty fitting in the FD, or at least compromising to do it. IMO, the Miata got that 'girl car' tag in-part because of it's size. So it seems there's that to deal with too.

 

when was the last time you saw a concept 3 rotor?

i have done a few 20B swaps, one of them running the stock JDM ecu, and my own car was a DD for 4 years, when i'm telling you its not practical i'm not just saying that....

i will grant you mine was a turbo, but i wasn't running it any richer than a stock Rx8, mileage on the 1,000mile sevenstock round trip was 19.9, mixed its 15-16, and if you step on the gas its single digit, basically its 50% worse than a 13B...

 

might be the perspective, but the BRZ looks bigger than the chevy parked next to it....

 

Your still thinking in terms of the old 3 rotor. Dont forget the new engine would be much lighter and made of all aluminum like the 16x. Hell the all aluminum 13b short block only weighs about 110lbs. Also cooling a NA 3 rotor isnt much of a chore with all the r&d already done in the modern day racing style cooling mods. There is nothing impratical about having a 3 rotor. My build is gonna show everyone a rotarys true and FULL potential. By the way, do you think the Zr1 guys are complaining about fuel economy?

 

If YOU wanna say it's impractical then have it your way. I respectfully disagree! Your fuel economy is 50% worse in your experience based on your designed and tuned swaps. If you did what I think you did and it minics every 20b swap out there, then your fuel economy esimate will never show the true potential of the engine. Discussing fuel economy on a swaped set-up shouldn't even really be up for discussion if your not gonna do all the things neccessary to help the larger engine make better fuel economy in it's new chassis. What things did you do in all those swaps to help fuel economy?

Did you ever try to run negative split in the low vacuum ranges?

Did you re-engineer the intake to have only the primary ports supply the engine in the low rev ranges like the Renesis does for light cruising duty?

Did you experiment with direct injection?

Did you re-gear the transmission or swap in a t56 to lower the cruising rpm's to take advantage of the improved bottom end torque the 20b makes on the highway? If your concerned about fuel economy, this right here is the most over looked thing that should be done. You just can't expect a larger displacement engine to have decent fuel economy when you mate it to a transmission that's geared to a lower torque engine. Lower torque engines need the higher revs to maintain speed while cruising....20b's don't. If you didn't modify the gearing, all your doing is reving the larger engine higher than neccessary under all conditions.


Now about that stock ecu swap you did! 20b stock ecu is designed to run the stock twins (which we know make boost really early in the rpm range). 20b made boost even faster than the 13brew because it's heavier Cosmo sedan application needed the torque to get the heavier vehicle moving. My point is anytime your making boost, your using more fuel and economy goes down along with it. So giving your 2 cents on fuel economy isn't helping much since your still turbo. That's why were discussing the potential of a NA 3 rotor (which IMO can be VERY practical if engineered correctly).

 

There will be so many more members for our wonderful forum!

 

You lost me there chief. I have no idea what gave you the impression that I believed the RX-7 is a modern marvel.


Ed,

I would appreciate if you would please enlighten me on how unrealistic it is. Seriously since you have only been on the forum for less than a year I'd love to hear your perspective.

BTW you probably missed this:

Let me decipher that for you. The Rx-7 cost $35,000 in 1992. Now due to inflation, $35,000 in 1992 equates to $58,068.82 in 2013. So care to tell me how unrealistic my figure is? Maybe 50K is too cheap for a 400 HP Rx-7. Maybe it should be 70K....

CPI Inflation Calculator

 

lmao! when i pulled the 3 rotor out of my FC, the Rx8 was not out yet, direct injection was something Mercedes did in the 1950's, negative split was BAD, shoot we were still arguing about the firing order! think about how long ago that really was. if i was going to do the 20B again, i'd go na for sure

the truck my friend built was running a completely stock 20B, engine, turbos ECU, and everything.

Re fuel economy; you're wrong, an OEM has to keep the cat in one piece, and that means running a rich AFR, even NA. look at the Rx8, the AFR's @wot are in the 10's...

and actually the Rx8 is a great example, there's no turbo, yet they only get 18-20 mpg in the real world (i've had 3), in fact the same trip back to LA i got 23mpg in the 8, vs 20 with the haltech, vs 12 mpg with the stock cosmo ecu (the truck gearing put it in open loop) vs 24 in my stock 79 Rx7.

you of all people understand the effort engineering a power train really takes

 

I just don't see a Gen 1 car putting down that performance for that price. GM can make a Carbon fiber Zr1 cheaply because they make boatloads of cash in every other aspect of their company. Mazda doesn't have that financial flexibility.

My opinion, we have two options for the next RX:

A light small "driver's car" for under $40k, or
A monster 350hp+ tire burner for SIGNIFICANTLY more cash $70k+



If you want under 2800 pounds AND 400 hp, we need to look at similar performance cars and add 10% "first generation R&D" tax.

Here is a quick list off the top of my head...

Well the ZR1 is too heavy, scratch that
Viper is 3500 pounds, woops


-Ok down the food chain...

e46 m3 was 3400 lb, damn
Lotus Evora, 3100 lbs, not light enough
370Z 3200 pounds, damn


My point is, making a 2800 pound car nowadays is INCREDIBLY difficult. Not impossible, but to do so you need to lighten everything else, namely the size of the engine, seat sizes, axels diameters, drive shafts, transmission ribbings get shaved.

Also remember that all cars come with infotainment systems and 7+ speakers, 50 pound wiring harnesses for government mandated Traction control, 4 channel ABS, and other crap. Name a new car with less then 4 airbags. I can't think of any.


OK enough of those comparisons, I'll pick one car, the 2014 Porsche Cayman S. Its pretty damn close...
2950 lbs dry, 325 hp, $64k base

That is 9 lbs per HP.

The FD
2500 lbs, 250hp, $55k (your math)

That is 10 pounds per HP

Your future RX
2800 lbs, 400 hp, $50k

7 pounds per HP
---------------------------

If Porsche, with its insane resources, decent amounts of financial security, and nearly a decade of engineering on this platform, cannot meet your specs for under $65k, how the hell is Mazda supposed to?

Also remember that Mazda will have a decent warranty on this new car as that is what is the norm nowadays, they will error on the side of reliability instead of magazine bragging rights.


Nothing personal, just my 2 cents.

 

Porsche is charging that because it's a Porsche, not because of the performance specs or power to weight ratio per se. I'd also be willing to forgive some of the Porsche finishing materials, interior, paint quality, etc.

Mazda already makes a "small light drivers car for under $40k". It's called a Miata. Nobody who's in the market for cheap/simple is going to buy a rotary. That territory is owned by piston motors. Trying to sell a rotary in this category, to these buyers, is a fools errand. Why would you buy it unless you're just a rotary fan boy?

Hate to keep beating a dead horse, but since everyone seems to want to gravitate to what's out there: As I posted a few pages ago, Lotus is already making this car... it's a 2600 lb, 345hp Exige S for $70k in both coupe and roadster form. They're no volume producer like Chevy, or even Porsche. You can't tell me Mazda can't hit those targets for less money. I'll bet you nobody who buys it gives a **** about the gas mileage either.

 

^Think of the company as a whole though. Mazda is fighting REALLY hard to up their fuel efficiency average as per the new US Federal guidelines get higher and higher.

I personally wouldn't buy an RX for more then $70 for any reason. For that money I would want a Furai. Even for $100k + I think the Furai would be a better seller. Its THAT much more special, they can play on the low volume as that would help sell their cars. In addition it works as a halo car AND doesn't negatively impact their fuel efficiency average.

Outside of the US (Middle East) the Furai would sell like hotcakes, (this doesn't hurt the US side of things for mazda) and helps make the product more profitable.

 

^^^^

LOL, Mazda mostly sells economy cars dude. If they have fleet mileage problems, everyone else is doomed.

Also, a Furai is a carbon fiber ALMS racecar. Get real. It's not and would never be a street car and would be $250k+ I think you have a distorted view of what $50-$70k buys you anymore, so maybe you aren't the target market. Go buy a BRZ.