GtoRx7.

iTrader: (12)

Thanks guys for all the kind words :-) minor update the throttle is hooked up now, i think only a formula 1 car revs faster :-)

ZE Power MX6

iTrader: (157)

That idling tone is music, can I get a sound clip of it going through gears so I can use it as my ringtone? LOL

You do amazing work Logan

Brody8877

iTrader: (10)

Mother of god! Props for an insanely godly build!

jantore

Realy a beautifull engone build. Is the throttle body adjustable at rpm or just set at a certain length?

Sounds good an all. Hmm 3 plugs would be great to put on my 4 rotor as well. But i think it would req a difrent ignition setup i guess.

Looking forward to getting my 4 rotor in a new chassi and get it running again.

Cheers for getting it running.

Looking forward to hearing it tearing down a track.

What did you do about noise reduction?

Mine was loud as hell.

129db with 2 mufflers.

JT

Grant M

whats the firing order?1-4-2-3? got to have that somewhere on the engine/car. all the best cars do

yagie

oh my. . . I got chills in the first 30 seconds looking at this. the metal work is immaculate by the way. Looking forward to a finished product.!

jantore

Im guessing it's 1-4-2-3 as most 4 rotors are and Mazda's where, and the same as mine.

JT

GtoRx7.

iTrader: (12)

Thanks Jantore, I remember following your build loved it's sound. I am using two borlas, it's too quiet now though. Techniques I use to reduce noise are not conventional, and the muffler doesn't have to work as hard. It's a by-product of making more power. Lol this is complex to explain without revealing too much.

The firing order is 1-3-2-4, which I believe is the true 787b firing order.

papsmagu

iTrader: (19)

this thread should be "stickied" to the top of this page....WELL DONE!

RCCAZ 1

iTrader: (10)

...any more running vids in the works?

GtoRx7.

iTrader: (12)

I will have some soon hopefully

rotorhausen

So far looks like a good amount of engineering has gone into this, mad props! Few questions though....

What type of racing are you guys doing with this? NASA/SCCA?

With the horsepower that is being projected to be made, regardless of tire, are there any concerns of overpowering the chassis to the detriment of mid corner and corner out speed?

I guess theres quite a bit of testing that needs to happen, but are you guys forseeing chassis/balance issues as a consequence from the added horsepower?


IMO N/A is best for road racing. In a dance where tenths of seconds mean 5 positions on grid, and consistant drivers are king, keep your snail I want predictable power delivery

muibubbles

iTrader: (36)

Because the forum and community is going to ****. its the "common theme" thats around all the threads and rotary meets lately... quiet pathetic what this "use to be" tight nit community has come to.

I never seen any of your work personally but I've always been impressed with the cars you've built (wish i was there when you went to KDR to show off some of your goodies). like seriously, you guys are building a 4 rotor and your thread has what 3? stars? haha the stupidity that has become of this forum...

good luck guys, keep posting, you guys really do some innovative stuff that we can all learn from

fallen751

This build is freaking awesome! I can't wait to see the kind of power this 4-rotor makes. Also, I am waiting with baited-breath for some videos with this monster revving.

RCCAZ 1

iTrader: (10)

Vids?

johnnymolloy

just wondering whats the limiting factor on why it cant rev any higher? wasnt there a 20b turbo that revved past 12k think it was built by mps

johnnymolloy

apologies just read the post wrong i would have taught as its na that getting it spinning as quick as possible is the goal to create more power(maybe max power is not the ultimate goal) i just taught 12k was conservative with the work done on it, when that fc was at if i remember correctly like 16k

Mdessouki

iTrader: (7)

I'll let someone more educated in these things give a definitive answer, but my guess is its making peak power somewhere around 10K. There is no point in revving the snot out just because you can...

johnnymolloy

yep im a noob when it comes to this sort of stuff so was hoping for someone to explain the reasons behind it so i can learn more

ultimatejay

iTrader: (1)

Logan, are you still using the stock spark plugs?

GtoRx7.

iTrader: (12)

It could take a book to explain the details of rotary rpm limits, I'll try to keep it short.

MPS never went past 10,000 rpm. The e-shaft did have a center bearing but is only part of what is needed to go past 10,500. They definitely never went to 16k, it just had a 16k tachometer.

Anything over 10,000 is a epic amount that is not easy to achieve by any means. And that is on a 2-rotor. 3 and 4-rotors are even more difficult. Hence why Mazdas 787b race car "only" went to 9,000 rpm.

12,000 is a limit I am setting for right now, and will not trust going over for fear of costly failure. Getting air and fuel into the motor alone at 12k is quite a feat nobody (that I know of) has done. So we will be the first on a 4-rotor to push the envelope this far.

Some quick issues that arise after 8500rpm ( Gmonsen has already mentioned most of these)

8500 rpm- stock upper limits with steel 2mm apex seals

9000 rpm- perfect bearing clearances, high oil pressure, side clearanced rotors

10000 rpm- Ceramic apex seals, 89 up factory rotors only, drysump system, even more oil pressure, good hardened stat gears (no Rx8), tension bolt mods.

10500 rpm- Lightened rotors, snap ringing

11,000 rpm- center needle bearing support and even more perfect clearances/oil pressure, special stat gear bolts.

12,000 rpm- VERY light rotors, special stat gear profiles, rotor gear mods, Big ol' ports and that is the tip of the iceburg!



I use stock until race days or dyno days, then I go with colder race plugs

Alldaybored

iTrader: (2)

wow just wow

johnnymolloy

cheers for clearing that up guys as i taught its way over my understanding,

none the less this is a very impressive build and wish them the best with the engine

jantore

Another issue is wear and tear on the side seals and corner seals.

The wear goes up exponential with rpm. At 9500 rpm the lifespan is perhaps 1000 hours tracktime. At 12000 rpm it might be 50 hours or less.

To get to 12000 rpm one might need to go for titanium rotors as well wich is quite alot lighter.

JT

Jimmy2222

iTrader: (3)

I NEED to hear more of this lol. Such a tease logan :P