rotary engine

[dangerman]

im looking for a new car to buy and i keep seeing RX7s with rotar engines
what are these things like to drive and own really

i hear theyre slow and dont have any torque and you have to rebuild them lots because theyre unreliable whats with that

how do they work no cylinders i know how do the combust do they use spark into a rotor or something

anyhow more importantly if i bought one a 1990 model around what sort of performance would i get from it if I wanted: exhaust and airfilter only and what about if i put a big turbo on it
thanks

[AndyMac]

You are 100% correct. All Rotaries need rebuilds after extactly 100 000 kays.

They have no power to speak of at all.

The rotor is actually made of plastic.

Man...Fark. Check out Ausrotary (www.ausrotary.com) All these things are myth's. A Rotary will last just as long as any other car, A rotor WILL need a little more respect and maintence thou.

[B0BB0]

Wrong mate,

Ever hear the expression Munch Munch piston for lunch

rotarys are cheap to rebuild, and with a few aftermarket mods they go very well, its quiet easy to get a s4 onwards rx7 into the 11's on a std motor, with just a hiflow.

[suburban]

yeh. respect to the rotors, they will cut the times with mild work

go more extreme and hold on !

[McLOVIN]

www.howstuffworks.com (http://www.howstuffworks.com)

[Mike_Hunt]

If u wanna know how a rotary engine works msg me sumtime, it's too long and detailed to go into here. Reliability wise they are excellent when treated with respect and maintained well (less moving parts than a piston engine) although they are possibly more susceptible to poor tuning than a conventional motor. Non synthetic oils that won't gum up springs/seals are often overlooked. Detonation can cause apex seal failure and because factory seals are steel (for longer service life) when these break/shatter they can gouge the housing and or destroy the rotor and these pieces on the way out can destroy the turbine blade (not cheap). You can get around this with carbon seals but the life reduces somewhat. Their real value is in the way they respond to turbocharging and the fact they can make/sustain big power levels with careful tuning without the need for million dollar hollywood parts (i.e. forged crank/rod/pistons, cams/gears, stroker combo's etc.). With the simple mods u mention can pull 220-230 kW and with a big turbo/exhaust/cooler/plenum up to 600kW and beyond isn't too hard (engine would need to be ported *flow* and dowelled *prevent twisting*). Definitely worth a look and don't beleive all the bullshit out there.

[dangerman]

so to make it strong like forge pistons in a normal engine you have to port it and dowel is it that all

what ecu is good for rotars can you remap standard ones?

you sound liek you know about mike thanks are you building one

[d0p3y]

Haltech is good
standard ECU is no good for more than exhaust and pod filter

[BDP]

im gonna hijack this thread sorta, anyone able to tell me how the rx8 renesis rotor differs from the older designs, say a 13b? so far ive heard the ports are at the sides now to reduce strain on the apex seals and that they have a system which sounds much like EGR to make them more fuel efficient and also comply them with modern emissions regulations, but other than that... any major changes in rotor shape? induction? etc etc

[McLOVIN]

The major change in the RENESIS is the side porting. All Mazda rotary engines have always had side inlet ports, but the exhaust ports were always in the housing. Now they're also in the end plates, like the inlet ports. A lot of people seem to dismiss this as nothing special, but it means a lot of differences in the way the engine operates. Fuel economy, power, etc are all affected. I'm not sure about the production version, but the engine shown at most major motor shows contained a very different shaped rotor. My guess is that it was just for show but it resembled a kind of 3-pointed shuriken (ninja throwing star).


Think of the move to side-ports like a piston engine that previously expelled exhaust gasses directly out the side of the block, moving to the current cylinder head design.

[SST Steve]

We have had big HP with reliability out of standard 13Bs
with nothing more than Intercooler, exhaust, Turbo, and a well tuned Wolf 3D(+ the secondary injectors upgraded after 300rwhp) even in race cars like Maitland performances S4 RX7 with 330rwhp all day on a race track ( stock S5 import motor and hiflow turbo)

[tomj]

How quick would a pink bmw be with a 26b?

........ .... ......... ;)

[Mike_Hunt]

What wlfpac mentioned about the renesis is correct, another by product of this port configuration/style is it is easier on the factory seals. The rotors in this engine are currently the lightest mazda has ever made and also the highest compression which will be awesome for use in an n/a periphal port combo. The ibrahim bros. beemer should if the chassis is worth it's salt and the tuning is any good (dunno what box yet - assume 5spd liberty) should run into the low 7's/ hi 6's depending on the clutch/rear tyre's/suspension/race weight etc.. (a lot of variables). Wheelbase doesn't look the best tho and they'd wanna have a good driver, last i heard it made around 900hp at the bags - dunno what boost/rpm tho.. In answer to another question yes i am currently building a s5 combo and hopefully u can see what it's got early in the new year.. :D

[Mike_Hunt]

Oh and yeah microtech ltx12 probably the best value/suited ecu for a rotor and as far as i know u can't remap the factory job.

[McLOVIN]

I'm not a great fan of Microwrecks myself, so I'd also suggest the Haltech e6k or e11(?).

[SST Steve]

I think Wolf and Microtech are the only option for Rotos.
I could never recommend Haltech again for many reasons, but i'v never seen one on a Rotary.

[BDP]

SST steve, as for running an essentially stock rotary on a track, i hear cooling is an issue? and mods would only compound that. Thanks for the info lads, might just have to wait till someone cracks one open and photos the guts :P

[hks-s14]

I am sure if you do a little bit of searching, there will be heaps of photos of scrotary internals.

[McLOVIN]

Avatar thief!!!!!!!!

[got boost]

rotas are a good cheap way to run good numbers
my old rx3 had hi flow S5 turbo, small cooler, wolf 3d ran 11.5's 120mph. but had a few motors on the way.
just stocka's and chuck the go gear onto them.
give a them a go they r great fun.
i just bailled a guy up with a mazda 1200 ute to buy it (R100 Style) cant help bad habits i guess

wlfpac ive GOT BOOST but i aint no bitch LOL : Þ

[McLOVIN]

You aint coo unless you got boost.

[SST Steve]

We've got some open now if you want a sticky.
Good Radiators in Rotarys is the key to a reliable setup.

[Boza]

nothin beats the good old rotors. they're good reliable horsepower when tuned properly and can last well over 100,000 k's if not beaten to death everyday and without constant hot shutdowns. my old 808 with a trusty old Samson crate engine with a digi 1 pro, 12a turb squirters and a greddy tdo6 kit managed an 11.9 @ 112mph on a measy 7 psi and the engine is still goin strong and has been in tha car 3 yrs. me be gettin another asap as my wrx won't keep up with big cc motorbikes...

[stacked]

some one asked for a picture of what's under a bonnet

http://www.geocities.com/ripauspics/nightcruise004.html

this is underneath my S4 RX7, will change on tuesday when i get pod filter will also upload before and after results of the dyno runs.

this is a 12a turbo old but good technology still

http://www.geocities.com/ripauspics/nightcruise002.html

[AndyMac]

EMS is another common ECU in rotors.

[SST Steve]

Its hard to find someone dealing with EMS in WA.
Their not to bad but the PC software is the worst i have used

[stacked]

i've started saving for EMS what are the microtech's like on the rotaries

[Boza]

microtechs on tha rotor motor are a proven good thing. Look at what most of the quickest rotors in Oz are runnin.

[stacked]

yeah i've had quite a few people reccomend the ltx8 as a unit how much is that worth?

[munchmunch]

the ltx8 is really good my has one in his rx3 half an hour on rotomotions dyno and its running beutifully

[AngeLissA]

don't forget that chicks like rotors :D

[McLOVIN]

Especially series 4 convertibles eh?

Too bad you can't get LADYRX plates though :p

[SST Steve]

Rotos are the only place i'd recommend for Microtech as Johns a Legend with Chookies and Microtechs.

[Mike_Hunt]

Regardless of what any1 thinks of him, mick munro pulled more hp out of lee sanders' car than anthony rodriguez did with the microtech, sumthin like 613@wheels vs 573 odd. Hehe and that was with the std s4/5 inlet manifold set up too.. chookies...

[suburban]

gettin the highest power aint the be all and end all tho. was it *reliable* (use that word loosly) power ?

a mates mate (ive spoke to him a few times) just had rodriguez over tuning his car. will be a weapon

[Mike_Hunt]

Seems to have been reliable.. haven't heard of any major cock-ups.. he did lose an engine or two in the past.. all depends on what trade off of ignition advance vs boost for power u want to run. A lot of ppl want a grenade tune for dyno comps and spank value and then expect to go and drive and arse about in it without probs.. I say sacrifice a little power for more reliability, u can get power back anyway thru manifold/intercooler design, turbo type, fuel and ignition system mods, porting etc.. Now all i gotta do is find sum1 to tune my lil beastie... :boink:

[McLOVIN]

I'll do it for a large 1/4 Pounder meal.

[Mike_Hunt]

Medium and u got a deal..