GoBerserk

Silver8,

I hope the 8 turns out like the miata. It'll be another fun to drive, lightweight, good handling, lots of potential, loved by its owners, easy to mod, reliable car. I've never met a miata owner that didn't love thier car.

Underpowered? Put on a turbo, that's what they're for. The RX7 was capable of huge amounts of power. The new Renesis, with it's improved port design will be able to make more power than the RX7 ever did.

wakeech

silver 8, stuff it. i've got my eye on you, and you're taking the thread off topic.

...not only that, but you're wrong. if you need me to count the ways, PM me, and i'll enlighten you.

BillK

Because perhaps that dealer is one of the many refusing to sell an 8 for MSRP or below?

O.R.A.

RX-8 lightweight at 3000 pounds? I don't think so. Shed 200 pounds and then we're talking. I mean, it's as heavy as a WRX with all it's AWD under there. Maybe lightweight when compared to the porker 6 at 3200 pounds for the V6...

:D

BillK

Actually the 8 really is lightweight, especially for a four door.

Now, start talking about cars like the BMW M3 that weighs around 3300 and the Audi S4 that weighs in at near 3900 lbs...

bgparsons3

I'd love to hear Paul Yaw and canzoomer's take on this development. Both these guys have a ton of knowledge and the resources to come to their own conclusions ... Yaw made some comments about 10 days ago that support this "position" from Mazda.

Guys?

blizz81

Nobody has brought it up explicitely in this thread yet, but what about concerns of acceleration at WOT as elaborated upon in the RN article?

As indicated in the WOT acceleration post in here, people have reported their cars accelerating faster at partial throttle than at WOT. I borrow the quote:

I guess it would take cold data to compare it to other cars in an objective sense, but some people seem to take notice despite the RN articles mention of how the "driver should not notice", which may (subjectively) suggest more of an effect when compared to other cars.

Also curious to me is how it retards timing along with the richening of the mixture (is that the scoop on "open loop"? as per my reply in the parallel thread in general discussion, I still dont know why this is necessary on a vehicle equipped with a knock sensor - seems like overcaution). Do all performance-oriented cars that recommend/require premium fuel do the same?

And the other question, as far as getting power back...wouldn't it be at least as much of a question of leaning out the mixture as it would be keeping the ECU from retarding the timing? Wouldn't you not have to worry about the effects of a lean mixture at retarded timing on a cat if you didn't retard the timing?

bureau13

Open loop means, in the general sense, no feedback system. In the sense of the ECU and fuel delivery, in closed loop mode it monitors air/fuel ratios via the O2 sensor and adjusts the mixture so as to keep the ratio at a certain level...generally this is done to maximize fuel economy at cruise. At WOT (I don't actually have to press the gas all that far to end closed loop operation on my FD, I don't know if that is the same as other cars or not) the O2 sensor doesn't react quickly enough, so the ECU goes open-loop and reads from its pre-programmed maps. This doesn't necessarily imply that the maps are rich, but usually there will be some margin of safety in there. As for the knock sensor, its reacting to something bad that has already happened...its not predictive, it is designed to simply keep the bad thing (knock) from continuing to happen, and pray that the first instance didn't break anything. You wouldn't want to use lean maps with no safety margin and rely on the knock sensor to save you.

Sorry if I'm rambling about stuff that is common knowledge...

jds

GoBerserk

3000 is a lot of weight. I'm still trying to figure out where they put it. But compared to simliar cars out there today it's pretty decent.

The are only two production cars out there that I know of with acceptable weights, are the miata, and the elise, at 2300 and 1600 lbs respectively.

I wish car manufacturers paid more attention to enthusiasts. Mazda is pretty good about it. At least they paid attention to weight when they designed the 8 (carbon prop shaft). But when I get mine it's going to be pretty bare. No heated seats, no naviagtion; I don't want to lug that garbage around with me everywhere I go.

silver8

Keech:

First off, pound sand.
Secondly, save your breath (or key strokes), you might need them some day.

RobDickinson

Weight comes from extra bracing for those suicide doors, + extra space/body for the rear seats.

Some of it is triple layer steel w titanium coating + extra bracing. Looking at all the light stuff they used (ali rear doors, boned, carbon prop etc) I'm suprised it came out as heavy as it did tho.

Cant compare it to the elise tho, thats VERY minimal. alu bathtub body, with a VERY light/small engine (new toyota 190 USis getting is 50kg hevier than the k1.8), no ABS, no airbags, no power steering, no gadgets (air con, powered windows). Nothing.

Just engine, chassy, brakes/wheels/drivetrain etc. Not quite as minimal or light as some of the 7 clones (Caterham R series is 400kgish, or under 1000llb).

The Elise only has 120bhp standard, but still has a higher power/weigh to the 8. But it is very hardcore, and I dont expect lotus to sell that manu federal Elises realy, even with 190bhp and aircon.

blizz81

Yeah, I apologize for not heading to the web to read up about open loop and making you ramble. The thread was beginning to wander around a bit anyway, but that's no excuse.

Really my concern again is just a comparison of how much the timing is retarded and how rich the a/f gets under situations like WOT accel, with other performance-oriented cars. Like I mentioned in general discussion, another case of waiting for the CAN readers But listening to people say "The difference of the car backing off from partial throttle to WOT is more than previous cars I have owned" is tempting to take into a discussion.

(Me being one of the people that's purely satisfied with the overall power of the 8. Just concerned about things like the effect on driving feel and adjustments and having the most control out of the car's performance. If that means being more linear on the gas, so be it).

Tresch

I hate to be crude, but doesn't it bother anyone else that this gives lots of technical loopholes and sidesteps and fun facts.. but doesn't actually give ANY answers whatsoever? Not to mention brings up several other concerns...

Is the engine really so borderline that it has to constantly choke itself to keep from predetonating?? If even in it's stock form knocking is such an issue, what about when we start throwing aftermarket stuff on it and the ECU can't keep up, suddenly we have a bunch of toasted rotaries on our hands?

Except the JDM models don't seem to have this issue.. is their gas REALLY that much higher octane?

Also, from the way it's worded (and people have mentioned this before, I know) I would assume the ECU is doing this ALL THE TIME, not just on a dyno. A "high load" condition doesn't have anything to do with what gear your in or how fast you're moving. All it means is the engine is doing a lot of work! So what they're basically saying is that the ECU doesn't just choke on a dyno. It chokes essentially any time you have the gas pedal to the floor.

Finally.. chassis dynoing IS a fairly accurate science, just in a different way than engine dynos. Most performance people prefer the chassis dyno because it gives a more REAL number of how fast you can expect the car to go, because it is measuring the amount of work actually being applied to the ground, after all the power required to run the drivetrain and accessories is shaved off the top. Noone's trying to get 238hp on a chassis dyno, they're trying to get a number at the wheels that is decent relative to that. You can predict fairly accurately what the wheels horsepower should be based on engine horsepower.. and 180 at the wheels either means that the engine is underpowered, the driveline is HORRIBLY innefficient, or the ECU is messing with it.

In the case of the ECU, they haven't really given us any reason to believe that the conditions that occur on a dyno don't also occur on the street.

I dunno.. don't mean to be harsh, but to me it just seems like a diversionary tactic is all. Again I don't doubt the RX8 is a great car and plenty quick, but so is my prelude and IT only puts out 195 horsepower. with an extra 30 it would be just plain fast!

I really don't want to stir up much trouble, I just get impatient because big parts of me really want this car, but my sensible, logical side says to hold out for answers, and then ALL my sides get impatient :P

poison123

I think its a totally valid concern Tresch. Your right when you say this gives Mazda alot of escape goat options. Honestly they've already adjusted the numbers once by 4.8% exactly and now their saying its impossible to dyno the car. This along with the seemingly high load crap, well I guess that takes this car right out of track and any kind of racing events because those sure as hell will be putting a "high load" on the car. Sigh I really like this car, but I want answers that can be verified by a 3rd party and not mazda.

javahut

I'm no scientist, but my common sense (maybe not so common?) tells me that the "high load" would be related to the amount of inertia that needs to be overcome to get from a lower speed to a higher speed. Therefore, how "hard" you accelarate will affect how much load is on the engine, and as you get closer to the desired speed, the load would be decreasing. Also, the car applying "high load" system settings would be so quick that you would not really sense all this going on. Obviously, this would mean that the car does not "choke essentially anytime you have the gas pedal to the floor", as stated by Tresch.

What do you mean? In the opening post of this thread, they just stated a whole list of reasons that conditions on the dyno are different than those on the street. Did you forget already?

My suggestion to Tresch and posion123 is to go test drive the 8. If it pleases you and you like it, buy it. If it doesn't, don't. How hard is that?:D

nk_Rx8

Anyone want to ship over a container of our 93 octane to Japan and see what they get with their ECUs?:D

mullogutherum

Not true. They give a whole list of reasons why "[t]here is no true way to generate flywheel horsepower from a chassis dynamometer". But they state only *one* clear difference between conditions on the dyno and conditions on the street: "[o]nly the rear wheels are turning while the front tires remain stationary." (Or did you forget already?)

The condition which provokes fuel enrichment and timing retardation is simply described as "heavy load acceleration". As Tresch states, there is no reason to believe that this does not occur on the street.

Tresch

Also, don't forget the part about the DSC. they explain that with DSC, it does these certain engine management stuff. In that thinking, then the cars that are totally base without the sport or GT options, should be dynoing much higher numbers! Another hole in the theory. There are just too many holes. Nothing concrete. Lots of theory but no practice.

Then, as poison mentioned, there's the 4.8% thing.. that REALLY gets my skin crawling...who wants to take bets that mazda will lower it another 4.8% when the current return deal runs out? :P

I have! And I like the car for a lot of reasons, but I WILL admit, that as far as top end power, it didn't really seem to pull any harder than my Prelude, which is a 195 horsepower car. Granted, the torque curve was MUCH nicer, because on the RENISIS, the torque piles on thick and quick! Making that 159 ft/lbs seem pretty crazy! where on the prelude you don't get a good kick until you hit VTEC at 5,400 rpm.

But with all honesty, the VTEC is still pulling HARD up to the redline.. where the RENISIS felt like it just fizzled out.

I would love to do both a drag race side by side, AND a ROLL ON race side by side between the cars. My estimation is that the RX8 will win the drag by a decent margin, because of the RWD, limited slip diff, and 6speed gearbox advantages.. but in a roll on from about 40 miles per hour.. I bet the two cars would be pretty even, with perhaps a slight nod towards the RX8.

Frankly, if it really put out 238 crank hp... the RX* should CREAM the prelude in any straight line test.. but I just don't think it would.

Don't get me wrong, I love the car, but if I'm going from a 15,000 dollar loan to a 30,000 dollar loan, I want to make it worth my while! I like going fast. if I drop that much money, I want to be going faster than I am now.

The trouble is, the RX8 is the ONLY CAR ON THE MARKET that meets my other requirements! It's a 4 door SPORTS CAR. how cool is that? I don't want an EVO or STI.. some souped up junky econo sedan.. I want an all out ground up tiny lightweight rear wheel drive sports good that looks nice, is comfortable, and has easy rear seat access. But I also want it to go FASTER than my current car! hehehe.. *sigh* I'm just too picky :P

RX8-TX

OFF TOPIC: You just called for trouble.....:D

Tresch

Haha, ok ok.. well I apologize to any STI/EVO owners out there, it was a bit of an exaggeration.. but it's pretty widely known that neither of those have any spec of LUXURY in them. (though to be honest, I've never sat in an EVO) They're crazy fast.. but they're not crazy NICE. Different people have different priorities! I wouldn't look down on someone at all for wanting an EVO. they're badass.. just not what I want.

javahut

If you really can't see enough of a difference between your Prelude and the RX-8 to warrant the price difference, I think you answered your own question... the RX-8 is definitely not for you.

On the other hand, if you have any kind of feel for sport driving... not just who will win a "staight line race" (although there's no way a Prelude would even come close), the RX-8 is soooo much more than the Prelude has ever been or ever will be. Frankly, your comparison between the two is so absurd, I don't know why I'm even posting a reply. I guess my typing fingers must be restless.

Tresch

"On the other hand, if you have any kind of feel for sport driving... not just who will win a "staight line race" (although there's no way a Prelude would even come close), the RX-8 is soooo much more than the Prelude has ever been or ever will be."

I'm making the assumption right off the bat that you've never driven a prelude. I'm all about the corners.. in fact, I autocross my prelude regularly.. so do all my friends. In fact, a friend of mine, driving a prelude in STS, is currently leading not just his class but the entire REGION by PAX. KTHXBYE

Really though, don't knock it till you've tried it. The 'lude is a highly underestimated car. In fact, it's WEAKNESS is straight line performance, which is exactly WHY I made this particular comparison. If the RX8 isn't much faster than a car that frankly isn't that good in a straight line.. there's gotta be a problem.

Once again though, I don't want to dig myself too deep, because I HAVEN"T put them back to back, only used my comparitive butt dyno. Which says "RX8 has smoother and stronger low end, but prelude seems to pull as good or better at the top"

*shrugs* so.. please.. don't make accusations and judgements on other people's character from single comments on forums. Where did I ever say I only cares about straight line performance? Nowhere. This is what turns threads into flame wars. Just a tip

javahut

I made no character accusations. Almost anyone who is into any type of handling, cornering, "road racing" knows that a front wheel drive car does not compare. There's no front wheel drive F1 or CART for a reason.

Tresch

true, but being RWD does not instantly make a car handle good, nor does FWD instantly make a car handle bad. A prelude will out turn a base mustang any day of the week. And I bet a CRX with custom suspension could probably even take the 8 in cornering.

I'm just saying stay open to things. Just because it's FWD does not make it instanly a horrible performing car. Trust me, one of the big reasons I want the 8 is BECAUSE it's rear wheel drive. I'm just saying that if I'm doubling my car payments I want significant improvement in all areas. straightline AND cornering.

Anyway, this is going off topic. I'll shut up now!

aar_eks_8

Doesn't Mazda have a spokesperson or a PR person....people keep using "official" word from Mazda....shouldn't it be undersigned 'Mazda' and not the name of an employee....? just curious........