Mazda RX8

[apoppin]

Originally posted by: dawheat
If the RX-8 does well, then the next RX-7 is rumored to be a 300hp, 2600lb, 2 seater rocket with possibly 3 rotaries vs the 2 in the RX-8. I still remember watching the last gen RX-7 dust the 911 Turbo of that year around the Nurbugring.

In any case, early review of the RX-8 have reviewers giving it high marks for a great chasis and balance. Yes you need to row the gearbox for max power, but the engine is plenty tractable down low. No you won't get a big rush under 5000rpm, but its plenty for city driving. And when you do get some open road...

The RX-8 can be viewed as a really upscale Miata - "handling" is emphasized and it does have some "go".

The RX-7 is the "muscle" car - the one that'll get you "in trouble".



I belong to the S.Cal Rotary Club . . . I have been reading some posts off and on . . . . I thought the RX-8 was already at a few showrooms . . . I'd better pay more attention to their threads . . . it's just that I NO longer have an interest in driving a "fast" car . . . I guess I "grew up" (gru-some).


RX8.com is "down" but you can check out their forums

Here is a link to their FAQS - its WAY too long to c&p

 

[bolido2000]

Isn't the torque curve flatter than the S2000?

I wonder if people will try to sell the wait list spots on ebay like they did for the 350Z...

 

[apoppin]

Originally posted by: bolido2000
Isn't the torque curve flatter than the S2000?

I wonder if people will try to sell the wait list spots on ebay like they did for the 350Z...

Of course . . . follow the link I gave you or go to the RX-8 Wanted/For Sale and click on the "EBay" threads

 

[slikmunks]

Originally posted by: JYDog
I think Rx8 is a sweet car but I myself would wait for a harder version, with more power, 247hp isn't much when the next honda Accord packs 240hp. :Q
Granted, the Rx8 comes into its own on the handling side, still I would want alittle more straight line punch.

rx8's also a little lighter than the accord, iirc, and the rx8 is rwd, whereas the accord is fwd...

 

[slikmunks]

Originally posted by: Howard
slikmunks, I read it, no fear.

You know, I hope Mazda comes out with a 2.0L or greater displacement RENESIS rotary (possibly a 3-rotor version?). Everything else being the same, it should make almost 400HP and 350lb-ft of torque. What a blessing it would be to have a turboed version.

they're looking to go greater displacement by widening the rotors... a 3 rotor renesis would be nice, but like i said in my other post, i don't know how they'd do it with the side exhaust and intake ports. The intake temps would be sky high if they tried to squeeze a third rotor in the middle that also had side ports... would they go side ports for the outside rotor and peripheral ports for the inside rotor? i doubt it... i wanna see how they're gonna make a 3 rotor... mazda'll think of something cool

 

[slikmunks]

Originally posted by: apoppin

Originally posted by: dawheat
If the RX-8 does well, then the next RX-7 is rumored to be a 300hp, 2600lb, 2 seater rocket with possibly 3 rotaries vs the 2 in the RX-8. I still remember watching the last gen RX-7 dust the 911 Turbo of that year around the Nurbugring.

In any case, early review of the RX-8 have reviewers giving it high marks for a great chasis and balance. Yes you need to row the gearbox for max power, but the engine is plenty tractable down low. No you won't get a big rush under 5000rpm, but its plenty for city driving. And when you do get some open road...

The RX-8 can be viewed as a really upscale Miata - "handling" is emphasized and it does have some "go".

The RX-7 is the "muscle" car - the one that'll get you "in trouble".



I belong to the S.Cal Rotary Club . . . I have been reading some posts off and on . . . . I thought the RX-8 was already at a few showrooms . . . I'd better pay more attention to their threads . . . it's just that I NO longer have an interest in driving a "fast" car . . . I guess I "grew up" (gru-some).

so-cal rotary club as in so-cal 7s? cuz if you are, woohoo! i'm not the only one on AT there's a meet tomorrow, btw, too bad i can't make it... there are a few rx8's on the road, but those were limited testing models or something along those lines, i believe. One or two have been spotted by the socal7s... as for the rx8 being an upscale miata with some go, it's bigger than a miata... by a lot... and it's got that "go" as for the rx7 being a muscle car... it all depends on ur definition of muscle

 

[apoppin]

Originally posted by: slikmunks

Originally posted by: Howard
slikmunks, I read it, no fear.

You know, I hope Mazda comes out with a 2.0L or greater displacement RENESIS rotary (possibly a 3-rotor version?). Everything else being the same, it should make almost 400HP and 350lb-ft of torque. What a blessing it would be to have a turboed version.

they're looking to go greater displacement by widening the rotors... a 3 rotor renesis would be nice, but like i said in my other post, i don't know how they'd do it with the side exhaust and intake ports. The intake temps would be sky high if they tried to squeeze a third rotor in the middle that also had side ports... would they go side ports for the outside rotor and peripheral ports for the inside rotor? i doubt it... i wanna see how they're gonna make a 3 rotor... mazda'll think of something cool

Mazda HAS a 3 rotor in Japan even 4 chamber 2.6 L engines (600 HP).

 

[slikmunks]

Originally posted by: apoppin

Originally posted by: Bignate603
They need something to overcome the lack of low end torque. That's the most fun part of a fast car. You hit the gas and it GOES.

I have two 1976 Mazda Cosmos ("rare" RX-5s) . . . if you want "torque" you change to a heavier flywheel. My stock 13B (1.3 L) engine put out well over 250HP with "normal" carburation. And can totally "burn" rubber first through third - I have "surprised" many a Porsche, etc (until about 120MPH when the Porsche catchs up and starts to pull away).

And emissions controls are more difficult to implement on a rotary engine without crippling it.

EDIT: Apex seals are no longer a problem. Even though the rotarys need to be rebuilt more often than a conventional engine (they now routinely get over 150K miles between rebuilds) they are MUCH easier to rebuild (two guys can lift the engine out of the compartment).

A "problem" with Rotarys is that they USE oil - the oil is metered (drop by drop) into the gasoline so you NEED to add a quart occasionally (even in a "new" engine) - the newer RX7s won't start if the oil is "low".

they are much easier to rebuild... 150k mi between rebuilds... that's a lot... i'm assuming those are n/a's... the turbo engines tend to need rebuilding sooner than 150k mi, but tha'ts partially because few people who spend the money to rebuild an engine keeps a turbo car stock... then you get boost creep and all sorts of other stuff that cna make ur engine go pop!

and the oil thing... it's no biggie, if you change the oil every 2500-3000 miles or so, you won't run into the problem unless you're hard on your motor... iirc, the oil isn't metered into the gasoline, it's metered into the rotors...

 

[slikmunks]

Originally posted by: Chadder007

Originally posted by: Eli

Originally posted by: specktre
everyone I talk to that claims to be into japanese sports cars don't like the 1.3L rotarty engine. they say that those motors aren't built for over 30,000 miles, they aren't durable.

I say they are morons. The rotary engine has less moving mass and less moving parts than a "normal" "rice rocket" motor.

I like rx-7's and I think the rx-8 is gonna be sweet.

my dream car (vin deasel's rx-7 in the fast and the furious)

well..... that's another area of concern. I have never heard of a rotary with 250,000 miles on it. The apex seals tend to wear out...

That said, it should last considerably longer than 30,000.

Ive seen one with 185,000 miles on it....BUT that is with the SECOND Engine, about to be third!

mine is on the 2nd engine, it was rebuilt at 148k mi, now it's got a big streetport, and the car's at 190k mi

 

[slikmunks]

Originally posted by: apoppin

Originally posted by: slikmunks

Originally posted by: Howard
slikmunks, I read it, no fear.

You know, I hope Mazda comes out with a 2.0L or greater displacement RENESIS rotary (possibly a 3-rotor version?). Everything else being the same, it should make almost 400HP and 350lb-ft of torque. What a blessing it would be to have a turboed version.

they're looking to go greater displacement by widening the rotors... a 3 rotor renesis would be nice, but like i said in my other post, i don't know how they'd do it with the side exhaust and intake ports. The intake temps would be sky high if they tried to squeeze a third rotor in the middle that also had side ports... would they go side ports for the outside rotor and peripheral ports for the inside rotor? i doubt it... i wanna see how they're gonna make a 3 rotor... mazda'll think of something cool

Mazda HAS a 3 rotor in Japan even 4 chamber 2.6 L engines (600 HP).

i know they do, but that's a 3 rotor COSMO, with peripheral ports. if you read carefully, i was takling about a 3 rotor renesis, with side ports... i know of the 3 rotor cosmo... 20bt, that's what i'd like to put in my rx... in about 4 or 5 years, if there's no 3 rotor renesis to put in....

and the 4 rotor (i think that's what you meant when you said chamber, which, if so, you mean 12 chambers (3 per rotor)) is the 767b, used in mazda's le mans race car... sweet engine, no way to get your hands on it without spending MAJOR bucks or getting someone to fab one for you... and i imagine the 767b could get way more than 600hp, since the 20bt (3 rotor) can get numbers of almost 800hp with porting, huge single turbo, and lots of fuel...

 

[slikmunks]

apoppin, u a socal7s member? www.socal7s.org? or is the so-cal rotary club diff...? never heard of so cal rotary club

 

[KevinH]

Slikmunks - Yeah you seem to know your rotaries my man. I used to own an 87 Rx-7. I LOVED the engine on that car. Unlike the old skool MR-2 I owned, when the engine decided to go, it didn't let me know (you know, the typical, shakes and shudders and vibrations that a normal engine makes). It just flat out died one day. It was the absolute oddest thing. To this day, I REALLY wanna know if it was me or if that's the nature of rotaries. That said, I would absolutely kill for a 93 and up Rx-7 as the prices in So cal are VERY reasonable for a rare 255 HP car that is fast as fvck. However, my mechanic buddy of mine who has had his hand rebuilding some Rx-7's (from early 80's and up) has said that he has seen quite a few 85-90K mile rx-7's needing to be rebuilt. What do YOU think?

kev

 

[KevinH]

While I'm asking questions, where do you go to find good info? I am dead serious about considering another RX-7 (like I said '93 and up), but NOT if I have to go through the trouble of rebuilding another engine. In So Cal, I've seen ads for clean title 75K RX-7's go for roughly 15ish...give or take a few. Although that price isn't back breaking, that's going to be my primary driver and I can't afford to sink 15 g's into a ride that "might" need to be rebuilt in a year or so....

In essence................HALP MEH !!!!




KEV

 

Howard
Two-strokes still have exhaust valves.

Two stroke engines have no conventional valves, all the gas management is handled by ports.
Some high performance two strokes do contain Reed valves, but these are nothing but small strips of metal that open and close from gas pressure, these valves prevent reversion of the incoming air/fuel charge, they are not actuated by camshafts.

 

[Eli]

Originally posted by: Roger

Howard
Two-strokes still have exhaust valves.

Two stroke engines have no conventional valves, all the gas management is handled by ports.
Some high performance two strokes do contain Reed valves, but these are nothing but small strips of metal that open and close from gas pressure, these valves prevent reversion of the incoming air/fuel charge, they are not actuated by camshafts.

Once again, beat by Roger.

Two-stroke engines do not have valves in the conventional 4-cycle sense. Yeah.. some do indeed have reed valves, but thats on the intake side.. not exhaust.

The exhaust port is cut directly into the side of the cylinder wall. When the piston moves down far enough after ignition, it uncovers the port... and the exhaust gasses move out at the same time that a fresh charge is moving in from the other side of the cylinder.

That's one of the reasons why older 2-cycles were horrible with emissions, it was hard not to draw some of the fresh charge out through the exahust port before it closes, in some cases.

 

Slikmunks - Yeah you seem to know your rotaries my man. I used to own an 87 Rx-7. I LOVED the engine on that car. Unlike the old skool MR-2 I owned, when the engine decided to go, it didn't let me know (you know, the typical, shakes and shudders and vibrations that a normal engine makes). It just flat out died one day. It was the absolute oddest thing. To this day, I REALLY wanna know if it was me or if that's the nature of rotaries. That said, I would absolutely kill for a 93 and up Rx-7 as the prices in So cal are VERY reasonable for a rare 255 HP car that is fast as fvck. However, my mechanic buddy of mine who has had his hand rebuilding some Rx-7's (from early 80's and up) has said that he has seen quite a few 85-90K mile rx-7's needing to be rebuilt. What do YOU think?

This depends entirely on how the car was cared for, if the previous owner beat the hell out of it and never changed the oil, yes you will find Rotary engines needing a rebuild as you have stated, but if the previous owner took care of the vehicle, didn't run it into the ground and performed the required maintenance at the specified intervals, then Rotary's can and will go past 200,000 miles with no problem.

Alot of people tend to forget that all Rotary's inject small quantities of oil into the intake tract, this lubes the Apex and side seals which is critical in the longevity of the engine, this oil is drawn from the sump, if the required oil change intervals are not followed, this oil will not only cause sludge build up in the oil passages and sump, but can also cause the oil injector pump to fail, this causes rapid engine wear and failure.

 

[Eli]

Originally posted by: Roger

Slikmunks - Yeah you seem to know your rotaries my man. I used to own an 87 Rx-7. I LOVED the engine on that car. Unlike the old skool MR-2 I owned, when the engine decided to go, it didn't let me know (you know, the typical, shakes and shudders and vibrations that a normal engine makes). It just flat out died one day. It was the absolute oddest thing. To this day, I REALLY wanna know if it was me or if that's the nature of rotaries. That said, I would absolutely kill for a 93 and up Rx-7 as the prices in So cal are VERY reasonable for a rare 255 HP car that is fast as fvck. However, my mechanic buddy of mine who has had his hand rebuilding some Rx-7's (from early 80's and up) has said that he has seen quite a few 85-90K mile rx-7's needing to be rebuilt. What do YOU think?

This depends entirely on how the car was cared for, if the previous owner beat the hell out of it and never changed the oil, yes you will find Rotary engines needing a rebuild as you have stated, but if the previous owner took care of the vehicle, didn't run it into the ground and performed the required maintenance at the specified intervals, then Rotary's can and will go past 200,000 miles with no problem.

Alot of people tend to forget that all Rotary's inject small quantities of oil into the intake tract, this lubes the Apex and side seals which is critical in the longevity of the engine, this oil is drawn from the sump, if the required oil change intervals are not followed, this oil will not only cause sludge build up in the oil passages and sump, but can also cause the oil injector pump to fail, this causes rapid engine wear and failure.

Interesting, didn't know that about the oil injection.

I bet rotarys would benefit a lot from leaded gasoline, due to its lubricating qualities.

 

[Gunbuster]

I wish mazda would slam the rotary in the protege to make a real kick@ass sleeper econo sedan

Heck put the rotary in the miata too

 

[WinkOsmosis]

Are Mazda rotaries available as crate engines?

 

[Eli]

Originally posted by: WinkOsmosis
Are Mazda rotaries available as crate engines?

I don't think so.. but there are places that sell otherwise brand new engines. Check ebay.. there are a few on there.

 

[Howard]

Originally posted by: slikmunks

Originally posted by: Howard
slikmunks, I read it, no fear.

You know, I hope Mazda comes out with a 2.0L or greater displacement RENESIS rotary (possibly a 3-rotor version?). Everything else being the same, it should make almost 400HP and 350lb-ft of torque. What a blessing it would be to have a turboed version.

they're looking to go greater displacement by widening the rotors... a 3 rotor renesis would be nice, but like i said in my other post, i don't know how they'd do it with the side exhaust and intake ports. The intake temps would be sky high if they tried to squeeze a third rotor in the middle that also had side ports... would they go side ports for the outside rotor and peripheral ports for the inside rotor? i doubt it... i wanna see how they're gonna make a 3 rotor... mazda'll think of something cool

Well, I hope they will.

BTW, does the RENESIS use port fuel injection?

 

[Mr.IncrediblyBored]

Originally posted by: Eli

Originally posted by: WinkOsmosis
Are Mazda rotaries available as crate engines?

I don't think so.. but there are places that sell otherwise brand new engines. Check ebay.. there are a few on there.

Yep, I don't believe Mazda sells brand new 13B crates. You can, however, purchase factory rebuilt engines from various companies.

Mazda Rotary Engines.com

 

[apoppin]

Originally posted by: slikmunks
apoppin, u a socal7s member? www.socal7s.org? or is the so-cal rotary club diff...? never heard of so cal rotary club

Damn I was sleeply last night . . . I put out a little "mis"info.

I have been driving the Mazda Cosmo since 1976 . . . I learned to rebuild the 13B almost in my sleep (which evidently was more accurate than some of my posts). . . .

Anyway, I am a(n inactive) member of the SoCalRXClub aka socal7 . . .glad to meet another member also on AT.

As to the RX-8 being likened to a "miata" is only in a "comparison" to the RX-7 . . . the RX-8 is the "handler" in the "grand-touring" tradition (fortunately with much more "go" than the Miata and 4-door ver is available). The RX-7 is no "slouch" in "handling" either but is much more of a (Japanese) "muscle car".

i know they do, but that's a 3 rotor COSMO, with peripheral ports. if you read carefully, i was takling about a 3 rotor renesis, with side ports... i know of the 3 rotor cosmo... 20bt, that's what i'd like to put in my rx... in about 4 or 5 years, if there's no 3 rotor renesis to put in....

I completely overlooked "renesis".

Yes - 4-rotor, 12 chamber . . . 600 HP is "basic" just like the 2 rotor can get well over 300HP if you aren't too concerned with engine "longevity" (as in racing).

I wish mazda would slam the rotary in the protege to make a real kick@ass sleeper econo sedan

There are plenty of "projects" that do just this . . . the 12A or 13b engine is so small and light it often has more "room" than the 4-banger it replaces,

As for metering the oil being "no big deal" . . . it used to be a major problem with Rotarys through the 1980s - the oil has to be changed (religiously) every 3K miles or you are injecting dirty oil . . . and lazy owners that wouldn't check the oil levels - the oil would drop and would frequently "blow the engine" giving rise to the FUD that rotary engines needed rebuilding every 30K miles . . . Actually, the earliest Mazda Rotarys - the RX2 - suffered from weak Apex seals that deteriorated by about 30K miles . . . by the time the RX3 was out the seals were greatly improved (to lasting well over 100K miles) - but the damage was done to Mazda's reputation . . . . That is why Mazda introduced the RX-5 (the Cosmo) in 1976 with the then unheard of 5 years and 50K mile bumper-to-bumper warranty (thats when we got one). Emission controls were a MESS with 3 sets of POINTS . . . however, the "satisfaction" from "blowing away" a much more expensive Porche was "priceless" . . . and the Cosmos were RARE - only about 2000 were imported in the USA, model years 1976-1978.

BTW, I am selling both of my 1976 Mazda Cosmos . . . I had a major accident so I can no longer work on them and they are deteriorating . . . do you think SOCAL7 would be a good place to start (I don't want to go eBay and prefer dealing with a "local" buyer)?

 

[Howard]

Roger... is this picture wrong?

Text

 

[Eli]

Originally posted by: Howard
Roger... is this picture wrong?

Text

That is a diesel 2-stroke.. which I have never actually run across.

This is the type of 2-stroke we're talking about. You know, the normal kind.