IV-Rotor Build: 12 plugs/ 9 bearings/ 8 ports = 1 monster

[GtoRx7]

The day has arrived, time to start the Defined Autoworks 4-rotor build thread. Some of you may have noticed our signature 3-rotor track FD hasn't been doing much. That of course is because it was being built into a 4-rotor track machine.

Since this was a long term project, I was able to very very carefully plan the whole thing one end to the other. Every single piece of data learned over the years with n/a tuning has been put into this one engine. Nothing was compromised and its built to be my ultimate vision of naturally aspirated horsepower. Because of that, certain parts of the car wont ever be photographed and are kept in "area 51" for the time being.

This specific 4-rotor is unlike any other. Its in-house name.... D26R

-Here is a cheat sheet on the specs it was built to-

Three plugs per rotor (just like the 787b 4-rotor)
Aluminum front and rear side housings
4-piece custom eccentric shaft
5-main bearings for very high rpm capacity
9.7:1 rotors, extensively lightened
race bearings throughout
2mm ceramic apex seals
Full custom p-ports in all housings
custom high strength stationary gears
Variable length intake, servo actuation (also like the 787b)
Custom slide throttle setup
4x2200cc injectors
Custom inconel header system

I've been working on this for 2 years, mostly on sundays or very late after hours at our shop. (pretty sure I earn one day a week off to work on promotional cars )

I will start feeding in pics over the next week or so, its hard to get any free time with all the work going on at good ol' Defined Autoworks.

[GtoRx7]

First up, the transmission. My old faithful T5 dogbox was not going to handle the 4 rotors power potential, so a upgrade was needed. Using our nascar connections was the obvious choice This is a Mid-valley engineering 4-speed unit. I tore it apart to inspect it..... okay I tore it down because I wanted to see how badass it was! Gun-drilled high strength massive trans shafts. All needle bearing support, internal oil pump, ultra lightweight gears, reem polished. This thing is a work of art!

[GtoRx7]

Here is the mostly real mockup 4-rotor attached to the 4-speed.



The chassis needed a nice overhaul before accepting the 4-rotor. After staring at it for many hours I had a vision of how to make it much easier and cleaner to work on. The engine bay and shock tower needed some modification to fit the variable intake as well. That will all make sense as we go along

She looks like a dirty POS. But give it a chance





Now I did it. Whole firewall gone. No going back now!

[GtoRx7]

Beginning of the new cage/tube structure. This is a superior design in terms of chassis stiffness.







The "tripods" as I call it, fully in place.

[GtoRx7]

All the sheet metal was bead rolled for strength

[GtoRx7]

[RICE RACING]

I love the project, sad thing is a little 2.1 lt 4cyl turbo (like Toyota 3SGTE) will make about 200+bhp more have much more mid range power, and be as if not more reliable.

Fantastic project though

[GtoRx7]

Originally Posted by RICE RACING

I love the project, sad thing is a little 2.1 lt 4cyl turbo (like Toyota 3SGTE) will make about 200+bhp more have much more mid range power, and be as if not more reliable.

Fantastic project though

hmmm would have to see that to believe it. 3Sgte.... I've never seen anything great come from one. I'm shooting for 600-700rwhp, so what 800-900rwhp 3sgte can spool up at 5k making power to 11k?

And thanks

[RICE RACING]

Originally Posted by GtoRx7

hmmm would have to see that to believe it. 3Sgte.... I've never seen anything great come from one. I'm shooting for 600-700rwhp, so what 800-900rwhp 3sgte can spool up at 5k making power to 11k?

And thanks

IMSA had rev limits of 9000rpm, but from 5000rpm to 9000rpm it had 90% of its maximum power, something no NA motor can hope to do... power is what is important that is what does work and moves a car

Have a look 2.1lt 3S-GTE motor, single turbo raced at this race with a minimum of 850bhp and made that over a very wide rev range (note with inlet restrictor !!!) >

Ran rings around the 4 rotor @ Daytona 24hr (a year later from this video) and passed them like they were standing still @ Delmar street race final in 1992, in endurance events it was un beatable.... and reliable too (24 hour wins and 12 hour wins)

I hope you make a much more powerful version than the R26B as in the IMSA car with a muffler attached (that would pass the 108dB track side limit) it was a fucking turd! with only around 600bhp to 610bhp available quoted to me from Mazda NA directly.. this is v's the 680bhp run at LeMans.

Seeing is believing NA Rotaries are shit sad to say And turbo ones can never be made durable at the power a little 4 cylinder is proven to make.
This little 3S-GTE motor still holds lap records 20 years on! and it was durable and fast. Street track beat all comers 6.5lt chev Intrepids, 7lt Jags @ Sebring, you name it, Toyota OWNED it.
4 rotor was no where.

[RICE RACING]

I love your car though! and am rotary through and through, just wanted to share how the R26B went in reality with the might of Mazda Japan providing the engine at no costs spared (the ultimate in NA rotary at the time and still today) am hoping you can beat it with your development, but MANY MANY have tried, no one has ever really got anywhere near it......... couple in Australia have tried and basically went broke trying to develop it.

Seen some over seas with similar concepts and no one has done much with one.

Even if you can it will be still be down about 40% in peak power to a turbo ~2lt 4 cylinder and the durability will be not much better.

I can post up some video's of BMW's turbo (stock BMW production block) run in IMSA in 1986 and it raced at 850bhp and qualified at 1100bhp set speed trap record at Watkins Glenn (208mph) and won that race with ease. Lots of examples in history showing how superior these engines are............ sadly Mazda could never ever match them, be it their attempt to turbo the 13B or later when they fucked all of them off to Racing Beat and went down the 3 rotor then ultimately 4 rotor path......... sadly history has shown it is a shit concept, thus they are not made any more.

I still love them but
And you project is sick as fuck!
Looking forward to what happens and how much power it makes.

Keep up the great work.

[GtoRx7]

Originally Posted by RICE RACING

I still love them but
And you project is sick as fuck!
Looking forward to what happens and how much power it makes.

Keep up the great work.

Come on Rice, I knew you were going to pull up the IMSA toyota stuff. Those engines are not 3s-gte's. Can you show me where I can buy one of these toyota race 4-cly engines at? Or how much it would cost me? Where do I get the parts at? Who is running 700+rwhp out of a production 3s-gte now?

Yes in the 80's and 90's imsa at full tilt was similar to formula one status. Manufacturers were pouring millions of dollars into the race programs. Ford mustang 2.3 4cly was producing 650-700hp too. All of them were.

I'm not a manufacturer but built this 4-rotor as a human. Those race engines you speak of.... I don't know anyone who can buy one!

[RedR1]

Originally Posted by GtoRx7

I'm not a manufacturer but built this 4-rotor as a human. Those race engines you speak of.... I don't know anyone who can buy one!

this is reason why i love it. you don't have to be farting money and lighting cigars with $100 bills (though it helps). . . you give us normal folk what matters most. Hope

that's what matters most in the rotary world now, since we are relying on each other more than ever with almost no rotary OEM support unless you have names like Speedsource, Dempsey Racing, etc.

[RICE RACING]

Originally Posted by RedR1

this is reason why i love it. you don't have to be farting money and lighting cigars with $100 bills (though it helps). . . you give us normal folk what matters most. Hope

that's what matters most in the rotary world now, since we are relying on each other more than ever with almost no rotary OEM support unless you have names like Speedsource, Dempsey Racing, etc.

This engine in 1990 would have cost more than any IMSA engine LOL.

It's all time relative.

Not hating just saying is all.... I'll see what power it makes

[RICE RACING]

Originally Posted by GtoRx7

Come on Rice, I knew you were going to pull up the IMSA toyota stuff. Those engines are not 3s-gte's. Can you show me where I can buy one of these toyota race 4-cly engines at? Or how much it would cost me? Where do I get the parts at? Who is running 700+rwhp out of a production 3s-gte now?

Yes in the 80's and 90's imsa at full tilt was similar to formula one status. Manufacturers were pouring millions of dollars into the race programs. Ford mustang 2.3 4cly was producing 650-700hp too. All of them were.

I'm not a manufacturer but built this 4-rotor as a human. Those race engines you speak of.... I don't know anyone who can buy one!

Those engines today you can do it with a 4G63 (all off the shelf simple & cheap parts), and about 1/3rd what you have spent and allot simpler.

The point is the same.

[FDwarrior]

Originally Posted by RICE RACING

Those engines today you can do it with a 4G63 (all off the shelf simple & cheap parts), and about 1/3rd what you have spent and allot simpler.

The point is the same.

I can build a 4g63 that will make 600-700 wheel AND live at the race track for novice endurance races using only simple & cheap parts???

Guess I need to switch engines then.