Hello all you rotary nutters!

Sephitrask · 03-15-2011, 12:37 PM

you know, I was wondering what had happened with this project when I didn't see it in the last Modified. Look forward to seeing it at DGRR!

Modified Dave · 04-27-2012, 12:25 PM

Well, I have to apologize for not making it out to DGRR again this year. Last year it was my Achilles tendon (oh snap, literally), this year it was the engine build for the RX-8. My buddy Joe Ferguson and I have been working on a pretty sweet Renesis engine build for a long time now, and after a lot of waiting around on parts and some machine work we finally had everything together to do the build and swap it into the car. This happened a week before DGRR and I was hopefully I could break it in and do a quicky tune in time for the drive down, but things didn't go quite to plan (as usual). The engine was throwing a misfire code and I'm still trying to track down the source. My latest theory is a bad knock sensor or knock sensor wiring, having already looked at the fuel and ignition systems prior to DGRR.

Anyhow, I'm seriously bummed out about not making it this year, but hopefully Phil keeps this event going one more year for me

As for the engine build, the full story on it will be in the July issue of Modified but here's a few deets JIC you're curious.

-Racing Beat lightweight rotors, good for 10.5k rpm
-Goopy Performance refurb'd housings and apex and corner seals (we EDM wire cut the rotors to allow for the deeper seated FD seals)
- full rotating assembly including clutch and flywheel professionally balanced
- ported irons and LIM using Racing Beat templates and instructions
- all new OEM gaskets, springs, seals, rings, etc
- Mazdaspeed rotor bearings, flywheel (ACT ProLite) and pulley set (main and alternator, deletes a/c)
- Bully Stage 4 clutch kit

We're hoping to make some good all-motor power out of this build (once I get the misfire dealt with and the engine fully broken in, of course). I'll post up a dyno plot once she's tuned.

A few pics of the engine build, just for fun:

assembling the rotating bits to send out to the balancer

porting the irons...

Checking the porting against the template

Goopy refurb'd housing looking minty fresh -- they not only bring the chrome surface down to a flat, uniform, matte finish that's ideal for seal break-in and seating, they also media blast it so it looks like new from the outside.

Pressing in the Mazdaspeed race bearing

A rotor and Goopy (apex and corner) seals ready for assembly. Notice how Joe has marked them all up so he knows where to put each one after having carefully clearanced them all prior to assembly.

Lets build an engine!

That's Joe's old school 616 up on the hoist, waiting for a 13B swap and some other goodies. He's planning to bring it to DGRR next year.

GySgtFrank · 04-27-2012, 01:19 PM

I'm very glad to see someone from the publishing world take an interest in rotaries. Like you, I've owned cars that were far more powerful. It's just that there's something about the powerband and RPM potential of the rotary that keeps drawing me back. The enjoyment of running a rotary hard is greater than what I get from the more powerful piston engines that I've had. It's kind of a visceral thing for me. On the street that powerband is also a lot more useable, you don't have to hit 120 mph before things get fun.

Modified Dave · 04-27-2012, 02:54 PM

Totally agree with you, Frank. There's something really special about the sound a rotary makes and the way it delivers its power. For me this really came to light when I test drove AutoExe's RX8 demo car in Japan (about 4 years ago) at a private test day that Yokohama tire organized for some western journalists up at Fuji Speedway's handling track (sort of a glorified go-kart track that they also use for drifting, not the big GP course). At this same event I was driving all sorts of modified piston engine cars, from HKS's GR STI and Evo X to a modified MINI Cooper S and even a E90 M3 with that high revving V8. Coming from a racing background, I just loved the way the RX-8 felt in the corners and under braking, but was especially taken by the way the Renesis revved. I think they had the fuel cut set to 10k rpm, so I imagine the engine was quite modified but it was still normally aspirated so wasn't making a ton of power. But it was just so smooth and had a lightness to it (if that makes any sense -- the sensation was that the rotating mass was much lighter than a piston engine), it was really different and appealing to me. It was after that day at Fuji that I decided my next project car would be a RX-8 and here we are. My hope is that the engine build I've just completed will provide a similar feeling to the AutoExe car -- I've gone with lightweight everything, from rotors and flywheel to clutch and pulleys. If my calculations are correct almost 20 lbs of rotating mass has been eliminated during the build. If you can't tell, I'm really looking forward to getting this motor broken in and tuned so I can start to give it a proper beating!

GySgtFrank · 04-27-2012, 03:28 PM

I'm very interested to see how the light weight rotating assembly works out. I've always thought the strength of these engines was their ability to rev to high RPMs. If there was some way you could get the RPMs high enough and still feed the beast efficiently, they should make very good power. It's a thought I've been kicking around for a long time , but never had the time or money to pursue. I had a 1975 REPU with the 4 port 13B back before there were RX7s. There were times I took it to around 12K rpms momentarily, stupid I know, but I was a dumb teenager at the time. That truck took all the abuse I could shovel it's way and kept asking for more, it never did quit or give me any trouble at all. That little 80 cu in engine put the fear in quite a few V8 musclecars at the time.

Modified Dave · 04-27-2012, 03:37 PM

Don't worry Frank, you're not the only one who abuses their rotary, and I don't even have the dumb teenager excuse (unless we're talking maturity level, in which case I fall well within that age range). LOL, ok I just failed at the internet. Trying to fix...

http://www.facebook.com/v/10150558703197265

03-15-2011, 12:37 PM	#31
Sephitrask BOILED PEANUTS!!! Join Date: Jun 2010 Location: Jacksonville, Fl iTrader: (0) Posts: 257 Rep Power: 15	you know, I was wondering what had happened with this project when I didn't see it in the last Modified. Look forward to seeing it at DGRR! __________________ www.rotarycarclub.com *"The way a Rotary engine makes power is ferocious, much like having a chainsaw under your right foot."*

04-27-2012, 01:19 PM	#33
GySgtFrank Professional Stick Poker Join Date: Feb 2011 Location: Stafford, Ks. iTrader: (0) Posts: 1,005 Rep Power: 15	I'm very glad to see someone from the publishing world take an interest in rotaries. Like you, I've owned cars that were far more powerful. It's just that there's something about the powerband and RPM potential of the rotary that keeps drawing me back. The enjoyment of running a rotary hard is greater than what I get from the more powerful piston engines that I've had. It's kind of a visceral thing for me. On the street that powerband is also a lot more useable, you don't have to hit 120 mph before things get fun. __________________ 1979 SA22C (parts of one anyway) http://rotarycarclub.com/rotary_foru...ad.php?t=15585 1975 MG Midget (building) http://rotarycarclub.com/rotary_foru...ad.php?t=18681 1988 N/A SE model FC, dead stock and less than 85k on the clock. This one actually runs, so I don't fuck with it.

04-27-2012, 03:28 PM	#35
GySgtFrank Professional Stick Poker Join Date: Feb 2011 Location: Stafford, Ks. iTrader: (0) Posts: 1,005 Rep Power: 15	I'm very interested to see how the light weight rotating assembly works out. I've always thought the strength of these engines was their ability to rev to high RPMs. If there was some way you could get the RPMs high enough and still feed the beast efficiently, they should make very good power. It's a thought I've been kicking around for a long time , but never had the time or money to pursue. I had a 1975 REPU with the 4 port 13B back before there were RX7s. There were times I took it to around 12K rpms momentarily, stupid I know, but I was a dumb teenager at the time. That truck took all the abuse I could shovel it's way and kept asking for more, it never did quit or give me any trouble at all. That little 80 cu in engine put the fear in quite a few V8 musclecars at the time. __________________ 1979 SA22C (parts of one anyway) http://rotarycarclub.com/rotary_foru...ad.php?t=15585 1975 MG Midget (building) http://rotarycarclub.com/rotary_foru...ad.php?t=18681 1988 N/A SE model FC, dead stock and less than 85k on the clock. This one actually runs, so I don't fuck with it.

04-27-2012, 03:37 PM	#36
Modified Dave The Newbie Join Date: Apr 2008 iTrader: (0) Posts: 17 Rep Power: 0	Don't worry Frank, you're not the only one who abuses their rotary, and I don't even have the dumb teenager excuse (unless we're talking maturity level, in which case I fall well within that age range). LOL, ok I just failed at the internet. Trying to fix... http://www.facebook.com/v/10150558703197265 Last edited by Modified Dave; 04-27-2012 at 03:47 PM..

04-27-2012, 12:25 PM	#32
Modified Dave The Newbie Join Date: Apr 2008 iTrader: (0) Posts: 17 Rep Power: 0	Well, I have to apologize for not making it out to DGRR again this year. Last year it was my Achilles tendon (oh snap, literally), this year it was the engine build for the RX-8. My buddy Joe Ferguson and I have been working on a pretty sweet Renesis engine build for a long time now, and after a lot of waiting around on parts and some machine work we finally had everything together to do the build and swap it into the car. This happened a week before DGRR and I was hopefully I could break it in and do a quicky tune in time for the drive down, but things didn't go quite to plan (as usual). The engine was throwing a misfire code and I'm still trying to track down the source. My latest theory is a bad knock sensor or knock sensor wiring, having already looked at the fuel and ignition systems prior to DGRR. Anyhow, I'm seriously bummed out about not making it this year, but hopefully Phil keeps this event going one more year for me As for the engine build, the full story on it will be in the July issue of Modified but here's a few deets JIC you're curious. -Racing Beat lightweight rotors, good for 10.5k rpm -Goopy Performance refurb'd housings and apex and corner seals (we EDM wire cut the rotors to allow for the deeper seated FD seals) - full rotating assembly including clutch and flywheel professionally balanced - ported irons and LIM using Racing Beat templates and instructions - all new OEM gaskets, springs, seals, rings, etc - Mazdaspeed rotor bearings, flywheel (ACT ProLite) and pulley set (main and alternator, deletes a/c) - Bully Stage 4 clutch kit We're hoping to make some good all-motor power out of this build (once I get the misfire dealt with and the engine fully broken in, of course). I'll post up a dyno plot once she's tuned. A few pics of the engine build, just for fun: assembling the rotating bits to send out to the balancer porting the irons... Checking the porting against the template Goopy refurb'd housing looking minty fresh -- they not only bring the chrome surface down to a flat, uniform, matte finish that's ideal for seal break-in and seating, they also media blast it so it looks like new from the outside. Pressing in the Mazdaspeed race bearing A rotor and Goopy (apex and corner) seals ready for assembly. Notice how Joe has marked them all up so he knows where to put each one after having carefully clearanced them all prior to assembly. Lets build an engine! That's Joe's old school 616 up on the hoist, waiting for a 13B swap and some other goodies. He's planning to bring it to DGRR next year.

04-27-2012, 02:54 PM	#34
Modified Dave The Newbie Join Date: Apr 2008 iTrader: (0) Posts: 17 Rep Power: 0	Totally agree with you, Frank. There's something really special about the sound a rotary makes and the way it delivers its power. For me this really came to light when I test drove AutoExe's RX8 demo car in Japan (about 4 years ago) at a private test day that Yokohama tire organized for some western journalists up at Fuji Speedway's handling track (sort of a glorified go-kart track that they also use for drifting, not the big GP course). At this same event I was driving all sorts of modified piston engine cars, from HKS's GR STI and Evo X to a modified MINI Cooper S and even a E90 M3 with that high revving V8. Coming from a racing background, I just loved the way the RX-8 felt in the corners and under braking, but was especially taken by the way the Renesis revved. I think they had the fuel cut set to 10k rpm, so I imagine the engine was quite modified but it was still normally aspirated so wasn't making a ton of power. But it was just so smooth and had a lightness to it (if that makes any sense -- the sensation was that the rotating mass was much lighter than a piston engine), it was really different and appealing to me. It was after that day at Fuji that I decided my next project car would be a RX-8 and here we are. My hope is that the engine build I've just completed will provide a similar feeling to the AutoExe car -- I've gone with lightweight everything, from rotors and flywheel to clutch and pulleys. If my calculations are correct almost 20 lbs of rotating mass has been eliminated during the build. If you can't tell, I'm really looking forward to getting this motor broken in and tuned so I can start to give it a proper beating!