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00 MRS - 2ZZ NA
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OK, maybe I exaggerated about the SAFELY part, but it has been done:

http://www.newcelica.org/forums/showthread.php?t=254003&highlight=10,000+rpm

GTsRasta said:
Boosted2.0 said:
yup. The little ol 1.6 Liter 4A-GE made 250 HP NA, but it did it at like 10,500 RPM. As long as VE is high enough revs = HP. Same is true of the 2ZZ
I would love it if lilrocket came on here and gave a fully detailed summary of his 10,000 rpm exploits on his 2zz Spyder. Do you know the exact specs of it Boosted? He frequently says he beats the snot of his built engine at those RPMs.
GTsRasta said:
Boosted2.0 said:
He has only gone that high a few times. Hes revving into the 9000 range regularly on a built head and upgraded oil pump.
Oh ok cool. I know WAR broke a bearing when he revved his beast to 9,100 rpms. I guess 9,000 rpm is the limit with head work and an oil pump upgrade.
Boosted2.0 said:
GTsRasta said:
Oh ok cool. I know WAR broke a bearing when he revved his beast to 9,100 rpms. I guess 9,000 rpm is the limit with head work and an oil pump upgrade.
Take this how you want to, but I have serious doubts as to WAR's ability to build a motor properly. Hes had a few too many failures which are always "someone elses" fault.

You can rev way past 9000
But for suspended periods of time...I think not, haha.
 

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I wouldn't mind a 20B 3 rotor turbo powered Elise. Heck even the Renesis out of my last car, a RX-8 would have moved the Elise along pretty good. It had a silky smooth powerband to 9000 rpms, great throttle response, about the same amount of torque but crap fuel economy.
 

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00 MRS - 2ZZ NA
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That would be cool, but figuring how to stick it in a MR layout would be costly. Check out what MWR just said about having a 9,000+ rpm limit on a 2zz today:

http://www.newcelica.org/forums/showthread.php?t=263232

monkeywrench said:
I make no guarantees as to how well any of the parts will last at high engine speeds but here are my experiences:

We've had our race car's engine up to 9500rpm, bearings and oil pump are fine. No signs of valve float with MWR springs and valves. We only rev that high because with a big turbo it likes making peak power at 8500+. If your engine is making peak power around 8k as they do NA or with smaller turbos then there is no point in revving even to 9k. With a larger turbo next year I expect we'll be revving to almost 10k.

I used to rev our spyder's 1zz to 8500 on the GT35r but knocked some teeth off the timing drive. I stay below 8k now.
 

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the new 16X engine that Mazda released, has replaced the steel rotors and plates with aluminum ones (according to at least one article i've read) so the overheated and mismatched expansions should be a non-issue. its N/A like the Renesis its based on but with larger displacement, should have a reasonable amount of guts to it. it shouldn't have as much of a heat issue as the turbo'd ones did, but still, i can see a lot of problems in cooling the engine when you can't just blow air over the front of it.

getting that power to the wheels though, remains a horrible engineering dilema. so yes, i agree, it could be done if you were bored and had too much money, but if that's your case, why not just buy me the Elise I'm saving for after having sold my FD3S and call it a day? :)
 

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I have a 94 Rx-7 and I had an 04 Rx-8 that I traded in for my 06 Elise over 2 years ago. I loved everything about the Rx-8 with the exception of the poor gas mileage. I would prefer the renesis engine in the lotus, the engine just feels better (far smoother), has more torque and is very compact/light. Gas mileage was terrible, I doubt I got 15 MPG city with just normal driving.
 

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hrmm.. I actually still have 3 20B's and a couple of 13B-REW's sitting in my container behind the house... One of them I built N/A with ITB's that should hit 250-300hp, but I don't think I'd like trying to shoe horn that thing in and working out the drive line would be a PITA. These are a couple of my old cars that I built...



 

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I owned a 3rd gen twin turbo RX-7 for about 3 1/2 years (it only ran about half of that though LOL). A love-hate relationship lemme tell you. Gas mileage was ridiculous! I got 10mpg average combined highway & street. Reliability was unbearable. She broke down a lot and I had to visit the mechanic often. Those engines run hot and cooling was priority #1. It also burned oil like there was no tomorrow.

On the other hand, when the engine was in good shape it ran like like a bat out of hell. With a few mods it did 80-150mph quickly and left C5 Vettes behind on the freeway. Once those turbos started spooling around 2500rpms your head went back in your seat and stayed there until you let off the throttle. It had a lot of punch in a small package.

Having also driven an RX-8 I really think that engine needs a turbo (or two) to really shine. Regardless of what improvements Mazda has made over the years, even if it were the last engine in the world I still wouldn't put it in my Elise. I don't think they'd play well together.

...I do miss that sound though. :rolleyes:
 

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I owned a 3rd gen twin turbo RX-7 for about 3 1/2 years (it only ran about half of that though LOL). A love-hate relationship lemme tell you. Gas mileage was ridiculous! I got 10mpg average combined highway & street. Reliability was unbearable. She broke down a lot and I had to visit the mechanic often. Those engines run hot and cooling was priority #1. It also burned oil like there was no tomorrow.

On the other hand, when the engine was in good shape it ran like like a bat out of hell. With a few mods it did 80-150mph quickly and left C5 Vettes behind on the freeway. Once those turbos started spooling around 2500rpms your head went back in your seat and stayed there until you let off the throttle. It had a lot of punch in a small package.

Having also driven an RX-8 I really think that engine needs a turbo (or two) to really shine. Regardless of what improvements Mazda has made over the years, even if it were the last engine in the world I still wouldn't put it in my Elise. I don't think they'd play well together.

...I do miss that sound though. :rolleyes:
Yea, I also had a 2005 RX8 that I sold in Sept when I bought my Exige. The new Renisis engine is ok for a daily driver, but I agree it wouldn'l work well in the Elise/Exige.

Bryanf, Very Nice on the Datsun btw...
 

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I own an 85 Rx-7 with 138,000 miles never had a single problem. This car is a daily driver and is driven hard on a regular basis (usually shift when the warning buzzer comes on). As long as you wait for the car to warm up and don't over heat them they are great little cars. You do have to watch the oil level it burns about a quart every 2500 miles but other than that never a problem. I also have a 93 Rx-7 with 37,000 original miles the only trouble I've had with it is a coolant hose breaking.
 

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if your talkin Rotary, check this website out. www.7parts.com

he is one of my closest friends and i've helped him work on it time and time again. he will rebuild the motor himself, get it out and put it back in. made the car a full tube frame chassis himself in his garage.

fast as hell!!!! maybe i can get him to chime in, as he is a Rotary Master, IMO.

i've driven the car a number of times and actually won the SCCA Nationals(05) in it, before we both got disqualified for a non performance technicality.

you want torque???? this car was FAST!!!!! 500hp, ~400 torque, 1900 pounds ballasted to 2550, or something close to that.
 

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Surprising # of rotary owners or previous rotary owners out here. I really wouldn't mind having a rotary powered Elise. After selling my Rx8 for my Elise, the only thing I really miss about that car is the sound and the painfree reving of the engine up to 9k.

People complain about the maintainence of the engine but who doesn't check their oil level anyways? And adding one qt ever 5000 miles isn't bad, and that's only if you rev it. If you baby the car, you won't even have to add any additional oil between oil change.

But like everyone mentioned, just cooling and tranmission would be a huge engineering feat.. maybe if Mazda ever decided to make a AWD rotary vehicle, we can use the front end of that.. until then..
 

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As a rotorhead I just wanted to let you guys know that all rotary engines are DESIGNED to burn oil. A metering pump injects oil from the pan either directly into the rotor housing or in through the intake with the air/fuel mixture, depending on application. This lubricates the seals that are on the apexes of the triangular rotors. Poor gas mileage is the result of incomplete combustion and the excess heat is attributed to the same; some of the combustion happens in the thermal reactor (afterburner) or header for you guys. Smoothness of the engine all the way through high RPMs is attributed to rotational force of the engine staying as rotational force as it moves down the drive train,whereas in a piston motor the up and down forces must first be converted to rotational forces. Rotary powered Mazdas are always equipped from the factory with a buzzer that goes off as the redline is approached....otherwise you could be at 10k rpm and not know it because the vibration associated with a conventional piston engine at higher rpms is lacking. Also the rotary has 3 full combustion cycles on each rotor for EVERY turn of the crank and it utilizes all of its 70 or 80 cubic inches (on a 2 rotor), whereas conventional motors utilize half of their capacity for each turn and have one cycle. Yes the rotary is lacking in torque but it makes up for it with revs; horsepower is made through either. With only 3 moving parts in a 2 rotor engine, what could be simpler?;)
 

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Well I was referring to the parts required to make combustion and that would be the 2 rotors and the eccentric shaft, but we could also add in the water pump if you wanted to look at it that way.... also the dizzy is absent on '86 up rotaries (switched to electronic ignition) and the oil pump is a self-contained unit, not driven off of the e-shaft.
 

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Mazda's "racing heritage," if you can call it that has always been based on the same principles - lightweight and efficiency - This is what drove me to my first RX-7 in 1996...and for the last 10 years that's all i've known. Some talk about reliability...rotaries are some of the MOST RELIABLE engines in racing form...they aren't 300K mile endurance engines like toyotas, but rotary internals look great in race form with 1K-3K miles.

It's natural for rotarheads to want the best of both words. The nicest and lightest RW production cars on the planet (the Elise/Exige) and one of the most potent (arguable) engines in the world. It's no coincidence rotaries are banned from LeMans!

RE: Aluminum housings - looks like Mazda is revisting this idea with new improvements to the RENESIS ENGINE.

Next Generation Renesis (Rotary Engine 16X), photos from Tokyo Auto Show - RX7Club.com


It could be interesting...I'd still prefer to drop in a built turbo RENESIS instead of a built 4cyl or 6cyl...the sound IS intoxicating! Our 4cyc engines sound like ricerocket hondas and toyotas...the rotary is a monster! :)

the old 13B engines - two 550cc injectors (stock), two 680cc injectors, a walbro pump, a T04 turbo and you're at 375HP...stock internals, stock ECU w/piggyback

I loved my 6 foot flames...too bad the video is buried somewhere in an old hi8 camcorder...

The Mazda Furai is rear engine, rear drive...anyone for for Mazda or Racing Beat? ;)
 

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Mazda did sacrifice a bit on the 13-B Renesis to control thermal expansion and remove the infamous wear on the apex seals. The first RX-8 even used carburetors instead of having DI because the focus was on engine wear; not fuel or oil efficiency or weight of the block (the apex seals do great now, BTW).
So, with that behind them they are trying to focus back on those other areas with the 16X: light-weight materials in-between the cylinders, better low-end torque, better gas efficiency (more complete combustion) and oil consumption. The 16X motor does show a lot of promise for this application.
I agree with many of the other posts that a huge obstacle will be the lack of FWD transmission from Mazda for these. The one possible exception would be on their hybrid (both gas/hydrogen fuel option & mated to an electric motor) rotary in the Mazda 5/Premacy prototype.

I'll admit, if they do release a FWD tranny for the 16X, I too, will be searching Craig's List and eBay for an Elise/Exige with a blown up motor for cheap.
 

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I had thought to put an RX-8 engine and 6-speed sequential in my Sport 190 Series 1 car, but looks to be quite difficult.

I'm a big fan of RX-7 engine in the Standard Formula Mazda (derived (copied) from the Russell Racing Formula car (before they switched to current F3 based car)) and the RX-8 engine used the in the Pro Formula Mazda currently used in the Star Mazda Series.
The Official Star Mazda Championship presented by Goodyear Website
Star Race Cars Web Catalog
Rotary Rockets
The Official World Speed Motorsports Website

The RX-7 engine is bullet proof in the Standard Formula Mazda, mainly in that it doesn't blow up if you over-rev, so a great choice for an affordable school car as Russell used have to have figured out before the insane switch to F3 based school car and a turbo engine from the Evo. Competitive racers get about 2 seasons out of the sealed engine in the Standard Formula Mazda.

The sealed RX-8 based engine in the Pro Formula Mazda has been less reliable, despite the upgrades to fuel injection over carburated, Motec ECU over mechanical distributor and ESD ignition. Seems the main reason for poor engine reliability with the Pro Formula Mazda is the choice to not allowed closed loop lamda control, so easy to lean it out - driver controls the MAP setting, driver is the "knock sensor", and lean is fast. Too tempting.:shrug:

I much enjoyed racing the two types of Mazda Formula cars in Russell, Rototary Rockets, SCCA, and Star Mazda. But I bought an Exige S in '07, started tracking that, started running it in Lotus Challenge Series and CFRA in '08 and sold my Pro Formula Mazda this year.

I bought a S1 Sport 190 last year and thought about an engine / tranny swap from the Pro Formula Mazda - so RX-8 engine and 6-speed sequential. But measuring it out, was too long by about 3 feet. Could take out about a foot by relocating the dry sump, but can't take out much more, so would need to extend the wheel base of the S1. Looked for alternate sequential, but didn't find anything shorter that could handle the power.

Also didn't get a straight answer from Red Line Time Attack if the Sport 190 would be allowed in that series. So instead I'm focused on continued development of my street legal Exige that runs in Cup Class in Lotus Challenge Series.
 
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