20B N/A with RX8 rotors??
 

Well, I was just told that all my parts are cleaned and ready to be assembled..

But now I'm thinking.. Maybe I should go with 20B N/A??? Do anyone know if RX8 rotors could be used?? I think I've heard that you could use the RX8 rotors...

I'm now thinking about going old school and go 20B N/A Carb'd!

take to Logan with defined auto works in southern ohio. His FD is N/A and 20B and to the tune of 300hp

I've seen his work and talked to the guy who helped put it together...But his is EFI NA.. I believe. My guy is whom I trust and knows quite a bit about carb... he's just not sure about Renesis rotors as he hasn't taken one apart.. i'm thinking about bringing him one this weekend to take apart and compare the rotors.

I'm also waiting to hear back from Carlos Lopez. He and I talked about this before as my builder wanted to go NA/Carb 20B... now I'm thinking it might be easier and unique...

This is the picture Carlos sent me about a year ago.. I think this is the set up I'm now considering...

http://www.rotarycarclub.com/attachm...1&d=1227125627

My only concern with Renesis rotors is that they aren't designed to handle peripheral exhaust ports, so I have no idea how long the lighter/shorter apex seals will survive.

I bet Landers could prob. give you a pretty good idea whether or not they would work.

ahh... I didn't think about that... Hmmm..

Aren't you supposed to machine the rotors to use standard 13B/20B apex seals?
EDIT: Just searched evil forum and I guess it's not necessary, but I did see that the standard renesis seals warped too much on the peripheral exhaust ports so ceramics had to be used. I think if I were doing it, I'd use 13B seals. Also, the thread I saw was from 2004, so things may have changed.

I'm interested in seeing more input on this.

Yes you can use the rx8 rotors in an na 20b. The place i will only trust to do the rx8 rotors and has done them on numerous times. Is Roan At xtreme rotaries in Au. Trust me.. well worth the money.

Do not have shops around the state do your rotors and balance. Its a joke. Trust me, Been there done that. I'm not going mention names not that type of person.

Also the rx8 rotors will be machined to except the 13b style apex seals 2mm or 3mm.

Good luck with your project...

Is that a 20b with renesis housings? I never gave that any thought.

how where do you get a dizzy for a carbed 20b i was told on the evil site cant be done heck id do that any day for my sa.

yes it is
http://i112.photobucket.com/albums/n...6/20B-MSPb.jpg
http://i112.photobucket.com/albums/n...6/20B-MSPc.jpg

only issue i heard with that is the one exhaust port. and i think intake port is smaller than the others...

what would you guys use for carbs then ?

I dont think its worth the trouble going with RX8 rotors. The performance gain over the 9.7 out of the S5 NA motors wont be noticeable IMO.

What a waste of time.


-Ted

I'm starting to think that now.. I was only considering 8 rotors as I have a spare renesis at home.. I guess I need to see of I could get hold of some S5 NA rotors cheap:)

I kind of have to agree with you... But I think they are using aftermarket 3 rotor shaft and renesis stacks up nicely vs. going peripheral porting the housings. In some ways it makes sense... I guess you could go 4 rotor like this using Renesis engine..

Thanks for this link.. Damn, That thing isn't cheap!

I think Carlos Lopez also makes them. Not sure how much he charges though..

I saw a set on ebay for like 80 bucks..I almost jumped on it. But I figure I should buy a block first. LMAO:beatdeadhorse5:

would you have to make your own intake mani or does some one make a 20b mani for a carb?

Carlos Lopez makes one... as you could see from the previous picture I've posted...

I was told by my builder that he could build one also... I'm on full throttle for this so hopefully it will be built by DGRR :)

i guess i missed it, but whats it going in? the duece?

IIMO as stated its a bit of a waste of time.

The main problem is that even with a higher static compression, you still ahve to seal the rotor in the housing to make that compression. So all the machining, and the side seal differences of the RX-8 rotors will result in a loss of dynamic compression when compared to a S5 rotor designed to operate in this style engine.

And the dynamic compression the rotors make when they're running is ultimately what makes the power.

I understand classicauto! I've decided not to use the RX8 rotors.. I'm going to find some S5 rotors and start the build 'real' soon..

Better post pics and info as you go. Wounder if u can use jeff20b dildls trick with that dizzy. If I don't know what iam talking about on 1st gens u use 3 coils and 3 ignitors. On a 20b you would use 4 coils and 4 ignitors.

Can you post some more info on that?? As I'm kind of clueless :)

check my thread out for info
http://rotarycarclub.com/showthread.php?t=3618
basically trailing is stock 1 coil to control it threw the dizzy.
then each leading plug has its own coil. the spark plug wire goes from the coil right to the plug.

on my na 12a 1980 sa, i cant stall the car out now. what i mean is if i drop the clutch in first at a dead stop the car will buck once and pull forward. my car idles slightly under 1000 rpm. you get a much stronger spark on the leading plugs since each has its own coil.they only problem i can see with this setup is cause the leading now is a wasted spark setup. ie both plugs fire at the same time.i dont know enough about 20b's to know if that would cause a problem with the 3 rotor setup. if jeff20b shows up he can explain it alot better.


http://photos-h.ak.facebook.com/phot...00239_6476.jpg
http://photos-814.ll.facebook.com/ph...100584_498.jpg
http://photos-814.ll.facebook.com/ph...00585_1337.jpg

Gmonsen, from the other forum, is using the RX8 rotors in his 20B N/A. They thought he was having a problem with the rotors and side seals but it turned out it was something else. Logan at Defined Autoworks is building my 20B N/A and he says that there is no real advantage....to much possible downside for to little upside.

warwickben, So you're saying leading and trailing fires at the same time?? Hmm..

yeah... that's kind of what I read from Carlos Lopez.

I'm definitely going to go at this point with S5 high comp rotors.

Now I'm going back and forth about going with EFI or carb. If I could get a carb set up pretty cheap, I might just do carb.. If EFI, I know I could go NA now and go FI later and use the EFI.. Hmm.. decisions..

How much do you want to spend Phil?

http://www.tweakit.net/shop/product_...f02f2a1cab4045

Sweetness.

I fapped.

http://www.tweakit.net/shop/images/2...les_fitted.gif

It looks nice!!

wait.. I just found out thats the same set up as the picture I post earlier (from Carlos Lopez).
http://www.rotarycarclub.com/attachm...1&d=1227125627

i think you have this backwards. leadings fire at the same time and can be off of one coil and the trailings fire individualy.

look at the schematic(sp?)i posted on the last page trailing has one coil and works with the dizzy, leading has 2 coils one for each plug and fires at the same time. alos after to do this you can switch the way you hook up the dizzy with the trailing. ie plug wire from coil to dizzy you put in the leading spot and the plug wires get plugged in to the leading spots.

I actually ran those throttle bodies (obviously the two rotor, not the three rotor version) on my stock internal 12a motor (with a big honking Master Power 70mm turbo on it, and a Megasquirt controlling EFI) and made 238 RWHP @ 13.5 PSI of boost. They're -fantastic- throttle bodies, and I have the dyno sheets to prove it.

The same exact setup but with my bridgeport 12a yielded 398 horsepower at the flywheel on my engine dyno @ 7psi of boost at 11,250 RPM. So they can definitely breath. (Side note, the engine was practically un-driveable on the road... so.. yeah. What do you expect?)

sorry, i meant the schematic was wrong.

nah the schematic is right. trust me lol.