rotary crazy

In australia people are making 380hp to the wheels na for racing on peripheral ports 13b engines at 12,000 to 14,000 rpm.

And in japan the RX-8 is comon dinoed at 205hp-207hp to the wheels ( the car we get in my country is the japanese version).

gh0st

i think the rc211v's v5 engine is well over 100lbs of torque.. i think its more then our rx8s but dont quote me on that.

not sure if anyone has mentioned this yet, but the size and shape of the rotary allows you to not only push the engine really far back into the car(past front wheels for better centalized mass) but also it allows us to keep the center of gravity VERY low. pluss the rotors spin causing the car to behaive slightly different when compared to a piston car with the same weight/distabution/suspention and also the rotors cancel out the internally generated inertia. if i had to decribe it, id say it translates to more cornering stability i guess? it might be in my head, but ive always felt that i can cary more speed with a rotary powered car through a corner then say a car with similar weight/suspention.

imo, its a shame that the stock rx8s suspention comes so soft. with slightly harder suspention, and about 20-30 more hp, the car would have been close to perfect for a stock car in its price range.

denward

fullsmoke

Twice as hot is reference to the 1000. And degF and degC can both be seen as absolute scales. Absolute temperature (scale) means temperature measured on a scale with absolute zero as 0. This is conventionally measured in kelvins, and now rarely in degrees Rankine. Absolute zero corresponds to 0 K or 0 °R (−273.15 °C or −459.67 °F).

FS

RX8_Buckeye

Yeah I took thermodynamics and heat transfer. If 2000F is twice as hot as 1000F, then how do you explain this:

1000 F = 810.3 K
2000 F = 1367 K

2 x 810 = 1620 K. The Kelvin scale, which IS an absolute scale, says otherwise.

fullsmoke

Kelvin, turns out is on the same scale as Celsius (every interval division is the same). Celsuis was also invented before Kelvin. Are you saying they came up with Kelvin, an absolute scale--the MOST ACCURATE SCALE (as you say), and it just happened to be on the same scale as Celsius? I think not. F and C (Rankins and Kelvin, as well) are totally differnet scales--why compare them? They are SCALES--based off of different measurements and proportions, but both can define an absolute temperature where the kinetic energy of a molecule will theoretically approach 0. If you didn't read my last post, an absolute scale is qualified as an absolute scale if the begins with a true 0.

FS

p.s. I also took thermo and heat transfer. Look in your books or check out wikipedia.

JeRKy 8 Owner

Too much positivity in this thread. Where's Ike when you need him?

rkostolni

In regards to the rotary being the cheaper engine, it definitly is. A new Renesis is only $2500. My friend just replaced his VR6 at $10,000. Most piston engines are well more than $25,00.

Also, the Renesis has a major advantage in that most of the stress that a piston engine see's is stress from inertial loads, or the stress from the piston violently changing direction 100 times/sec, no such thing in a rotary. If it weren't for those damn Apex seals I think rotaries would be relatively industrable.

RX8_Buckeye

You're missing my point. All I'm trying to say is that it cannot be stated that 2000F is "twice as hot" as 1000F. If you're claiming that any temperature scale can be used, then why doesn't the math add up?

PaulieWalnuts

Nothing like a couple of engineering geeks going at it. Where's the popcorn?

StealthFox

introduce me to these girls that give a rat's *** about cars.

Nubo

Rotary advantage re: the RX-8

-good power in a small size
---allows sporty form factor while keeping 4 useable seats
---low polar moment of inertia improves handling and quickness

-smoothness
-wide powerband
-ability and willingness to rev high

StealthFox

are you talking about from mazda? thats a hell of a lot cheaper than i thought...

shakRpahX8

Stealth Get your own girls.
I'm keeping mine, I'm not sure about Rasp willing to share his girls with you
My girlfriends listen to me about my car better(or should i say more seriously) than my guy friends.

Oh and from what i know about Cappuccino by Suzuki
the biggest Pro is its size and weight
it's about 690kg which is not even a ton Feather weight!!
I also heard the balance distribution is about 49:51

missinmahseven

Is the Renesis that succeptible to ping? I mean, I know it'll kill wankels fast, but doesn't the Renesis have a knock sensor? That at least should hedge against ye olde ker-blammo..

fullsmoke

*sigh* Learn how to read.

Keyword is ALMOST. Don't twist my words.

FS

neit_jnf

the scoot motor uses 12A components

Mazmart

iTrader: (12)

I don't want to be involved in a fight here but I have to inquire what part of a renesis is being measured at 2000 deg F and by whom?
Paul.

RX8_Buckeye

Actually I think 1800F was stated, and it was the exhaust gases. I'd have to imagine that's in the hot-end before the catalysts. I don't know the source of those numbers. That's one reason I was asking about the statement "runs twice as hot as a piston engine".

Mazmart

iTrader: (12)

I won't argue with anyone about rotaries (including the renesis) exceeding the exhaust temps of your average piston motor but just like you, I was wanting to see the source of the statement if they are implying that the renesis is running that hot. I do know rotary exhaust temps can actually run 2000 degrees because I've seen it.

BOOSTD 7

You know how it works Paul, somebody reads something on the net and then regurgitates it 20 times ... all of the sudden everybody is saying it, and it's gospel.

2000F is possible under race conditions, or a car running high boost and super lean. No way a street RX-8 is going to get close to that, just off the top of my head I'd say 1400-1600 MAX, and that's probably even pushing it.

What does Rick say about it

zoom44

no it is not

zoom44

yeah @1600 is about what i have seen mostly on the RX-8

fullsmoke

I took a few pics of my Racing Beat technical catalogue. These figures do apply for extreme conditions and for non-renesis motors. Here's the section on exhaust tips:

Mazmart

iTrader: (12)

Jim Mederer of Racing Beat is one of the foremost rotary men this planet has ever seen. He is someone I had wanted to meet since childhood. I had the peasure of meeting him last year at Sevenstock by the way. His opinions are still highly regarded with me and in this camp (Mazmart/Downing-Atlanta). One of the few other men in the US who are spoken of, by those in the know, with similar praise and regard would be my friend and employer Rick Engman, the Downing engine man for the last 30 years. He said it would be typical to see temps around 1750 to 1800 on average at wide open throttle on a race motor under load but that many factors come into play. These include point of measurement (It could actually get hotter further from the ports), overlap, injector positions, ignition timing and air/ fuel ratios etc.
I think the most knowledgeable folks regarding the renesis temps right now would be Jim Mederer or David Haskell (From SpeedSource).

fullsmoke

I think I've met Rick Engman, the name rings a bell. At a rx7 meet in atlanta, I met lots of the employees of Downing. I have yet to go to Jim's shop though... Missed out on a free grand tour for the rotary gang here

FS