NashuaCLS

I am very interested in a RX-8 with at least 300HP.

2 Quick Question:

1) Is the MPS RX-8 with 300HP confirmed?
2) If Turbo Charger is not possible, How about an Electric SuperCharger (From TurboDyne or Garret)?

Sputnik

Officially confirmed? Nope
In the works? Yep.
300 HP? Minimum.
Full Sequential Manual? Yep.

Quote:

2) If Turbo Charger is not possible, How about an Electric SuperCharger (From TurboDyne or Garret)?

Turbocharging is not impossible. But take a look at the recent engine pictures on the "Boowana Quest" forum. That engine has two intake paths and throttle bodies, and as we have been led to believe, the higher HP version (the 250 HP 6 sp version) may have three instead of two. Trying to adapt an aftermarket SC or TC to that kind of setup is going to be very very difficult, especially for a "bolt-on".

Meanwhile, we're moving this to the proper forum...

---jps

NashuaCLS

very nice to hear...

Actually few of the "requirements" of my next ride:

Class: 4-doors 4-seats Sport Sedan/Coupe... (RX-8 qualifies for that)

1) at Least 300 HP... MPS RX-8 might do just that.. :D
2) AWD with perfect balance and handling (Ok the RX-8 is RWD... I can live with that as RX-8 is a perfect road handler)
3) SMG 6-speed.... :p MPS RX-8 gets one more tick.
4) NAV already confirmed on the current RX-8 ... another tick.

Finally at a price I can afford mid $35k (could you double tick that )

m477

Turbo is not impossible, it's just that the new rotary engine no longer has an advantage for turbocharging over pistion engines like previous rotaries had.

The prevailing rumor, though is that the higher power engine will be a 1.5l NA, assuming the hp/liter ratio is constant. The displacement increase would yield about 290hp.

rotisserie

Three seperate intakes for throttle bodies equals so major mulla

Hercules

If the RX-8 MPS gets AWD i won't buy it. Adding that much weight and imbalance to the car will make it worse not better.

Ideally though, it would be the RX-8 with lighter parts/materials and stiffer suspension, with an increased rotor width to get over 300 horses.

While the jump from 250 to 300 might not seem like a lot, factor in a weight decrease as well and you're talking about a mighty fast car

wakeech

what i think you really want is the AWD MPS 6, not the (big maybe around production) MPS RX-8

Quick_lude

SMG? Unless it's a unit like in the Ferrari or BMW that is FASTER than a manual gearbox, no thank you.. People play too many video games nowadays..

Sputnik

However you want to call it, SMG, MSG, clutchless manual, etc., I understand that the tranny that they are planning will be a 6 spd manual transmission, with a hydraulically actuated clutch, controlled by a computer. You should be able to control that computer by shifting buttons, and I believe that they are intending to include an "auto" mode also.

But that's all I've heard from "sources".

---jps

Quick_lude

Bah.. so no conventional 6 spd tranny?

jonny b

this might be dumb, but to me, widening the rotors is an obvious way to get more power, but wouldn't manufacturing costs be a lot higher than if they just did some other mods? with 300hp stis coming for low 30s, it would be tough to match that price if they make the rotors wider.

Hercules

I will not buy the car if there isn't a traditional transmission available.

As per the last quote, about the STis for low 30s... well it's a bad example. The STi removes all interior fit and finish and care, and puts it all into the power train and suspension. So while the STi might compete with an M3 in a straight line or whatever, there's a lot you miss out on as well.

I think Mazda could get away with a 300+ horsepower RX-8 that's lighter weight for around 40k loaded. But that's just my thoughts on it.

Sputnik

As I understand it, the "SMG" would replace the auto tranny, not the 6 speed. Which is why I'm assuming that it will have an "auto" mode.

---jps

Styjan

When I went to SevenStock this summer at Irvine R&D the VP of Marketing and a Mazdaspeed guy were there. In a speech to the crowd the VP said that the Mazdaspeed RX-8 was in the works and that the Mazdaspeed guy had promised him over 300hp.

They didn't mention any specifics about how it would make over 300 though.

wakeech

no, i wouldn't think so... most of the tricky bits to make would stay the same, with only the rotors, and e-shaft getting any wider/longer (in the same dimension)... there would probably also be very little to re-engineer, or big design problems posed by going for another 10mm on the rotor width... in all honesty, i can't think of a single reason why developing an engine with rotors 10mm wider (and producing it) would cost more than a turbocharging solution (with R+D, and manufacturing costs).

m477

Are you sure it was "over 300" and not "about 300"?

Not really. Mazda already made a 1.5l '15A' engine in the 70's. The only reason it never saw production was fuel economy, as those early rotaries had pretty bad fuel economy to begin with. Also, widening the rotors would probably be much cheaper than FI when it comes to warranty claims as well, meaning that they can then in turn make the MSRP lower...

Styjan

The VP definitely said OVER 300hp.

Styjan

Correction :

The VP was actually Charlie Hughes president of Mazda USA.

Did anyone else go to Sevenstock and hear this?

BryanH

The words I remember were "at least" 300hp. But I'm not 100% sure on this. Once I started hearing this guy rattle off specs on the RX-8 I wished I had a pad and pencil handy.

m477

Sweeeeet.... now where is that "monkey jizzing" icon when you need it? :D

MWG

I dont know if you would get the torque you want if you just made the rotor housing wider. I think you have to go to a 3 rotor. Buy it they can do it with some trick intake system. go for it . Just give us more torque. You guys know that horsepower is a different way to express torque. I think you will be able to bridge port a renesis and get more horsepower. but only so much.

MWG

I also think that is would cost to much R&D to make larger rotor because the rotor would take on different porperites. and would need more parts, redesigned rotors, E shaft , seals, rotor housing, etc.. You would only need two engine parts made for a 3 rotor ,a thicker center side housing, stationary gear and intake system of corse. you would get alot more torque from it . And Torque is what moves cars. but if they can do it with a trick intake system on a Renesis motor go for it.

wakeech

little point in retyping it all...

but i'll apend a little... if you choose to read around the forum and do some homework about it, you'll see that it's torque at the wheel which matters rather than torque at the flywheel, as i've seen you allude to in the thread specifically about the 3-rotor engine.

you are infact wrong about it being easier to make a 3 rotor in comparison to a wider 2 rotor, and about the bridge porting: bridging or street porting the traditional way (down) on the RENESIS would cause increadible overlap, and the area that the ports have is already bigger than they were in the Series 5 NA 13B's, and can certainly run more than 250 horses through them: in short, don't worry about porting, it'll probably do more harm than good to the weird and wonderful materials they've got happening in that engine (on the expiration side).
holy christ, that was one long sentance. :o

MWG

For one wheel torque does matter but it comes from the power that is made at the flywheel. less what is lost in the transmission and drivetrain but if you have on 150 ft-lb at the flywheel you are only going to have so much wheel torque from the gearing. Ok. Trust me that is why you don't have stock RX-7's going around beating Ferrari. Another thing you should know is I belive that the exhaust port on the renesis closes before TDC. and so you would not have any over lap because the rotor would be in the way until you had closed the exhaust port and if you ported down you would only do it a little because it opens pretty early and to make more power you need more volume of air and a longer duration.

wakeech

alright, alright... torque at the flywheel matters, but it doesn't tell you how hard the engine is pushing the car... as far as RX-7's versus Ferrari's, let's not get into apples and oranges: i'm on a fruit and BS free diet.
thanks.

have you observed how closely the rotor is to opening the inspiration port at 90 degrees ATDC (end of combustion event, BDC)?? in the RENESIS, the inspiration port has been moved far, far down the side of, the housing, not to mention the rotors are now scallopped on the edges to further advance timing already. adding a bridgeport (which would put and opening where in stock form there's a "fence" along the edge of the side housing) or a street port (which traditionally lengthens the inspiration port down toward the exhaust port) would certainly create some amount of overlap, quite possibly a whole lot. i know the port opens very early (only a very few degrees ATDC on the exhaust side), and to increase the duration of the inspiration stroke one would more likely extend the port upward, not down (to delay closing).
it's true that to create more force in the combustion event one needs more fuel to burn (air+gas), but having an inspiration stroke last longer than the rotor's 90 degree turn to BDC is not going to help with that... also, it's not empirically true that larger ports will "flow better", or to put it more properly, increase the volumetric efficiency of the inspiration cycle.

****, i've gotta go for a run... *sigh*