mperformance

class permits...so I'm doing it...needs to be ready before May 5th

remember my first circuit race? well the honda that won had 210fhp, 1.6 stroked motor with type R pistons and a bunch of mods. That engine will be installed in a 89 civic hatchback so it will be even quicker...

any help greatly appreciated

email me at: m_performance@hotmail.com or post some tips here.

SoRRoW

Good luck!

Take pics and vids

nimrodTT

What are you allowed to run intake-wise?

mperformance

just anything as long as I keep it 12a n/a

hey what kind of seals you guys recommend, I was thinking on building it for now with normal 2 piece atkins for this race. I plan on not reving it too high maybe 8tish so I might not even do the hardened stationary gears. Basically I just want the PPport to help up in the 6 to 8k range and try to keep it reliable by shifting at the end of the stock redline.

The idea is to have lots more power than the stockport but I don't really need that much if you consider that I need to be around 220hp - 230hp with the 12a. I'll crack open the engine after the race and as $ permits build a much better peripheral.

Terrh

iTrader: (7)

do it right the first time, or you'll be doing it the second time much sooner than you think.

What kind of weirdass intake manifold has to be run with a PP setup, I suppose it would have to be a custom jobbie?

And doesn't 8krpm seem kinda low when dealing with a PP? Might not even be on the powerband till 6.5.....

BRealistic

Is there any way to increase the size of the engine, like using parts of a 13b to get the wider rotors- or would that be cheating? It just deosn't seem fair that piston engines can change their bore/stroke, but rotaries can't.

mperformance

Terrh it's a matter of $$$, yeap I want to do it right but I don't have the $ yet. I still have to spend on the suspension which is really much more important than the engine now.

The good news is that I have a friend that is a great fabricator and the ports can be machined with no problem. The intake is basically the easiest to make since it's just two pipes that connect to the housing ports. My biggest problem will be finding the right IDA carb in so short time. like I said I might not hit the power band all the time but remember that I will be running a circuit race and the last time I was on the track my engine only saw 6k-7.5k at 2nd, 3rd, and 4th for about 20minutes. I think a peripheral will do wonders I just need to keep costs down.

Brealistic, well it's actually unfair for piston engines to run against a bridgeport or a peripheral port. That's why rotaries get banned everywhere. I might even get bumped after I win, if I do win.

Terrh

iTrader: (7)

12as are plenty big enough to beat on most boingers...

Siraniko

iTrader: (13)

i smell a 51 ida.

12abridgeport

i know people using holley 600 and new mazda factory apex seals on peripheral nitrous engines

peejay

A 12A with 13B rotors and rotor housings, is a '74-78 13B. My guess would be that would be highly illegal.

Why go with the Atkins crap? If you're going to keep it under 8500 then the stock ones are more than fine.

Remember guys, the R26B had an effective redline of 8000rpm at LeMans, 9000rpm for "emergencies". Not bad for effectively two 350hp 13B's running a lean A/F mixture for best economy! Peripheral ports don't equal stratospheric RPM.

WackyRotary

Why don't you simply scratch off the 13b marking on the rotor housings and etch out 12a on them!

Anyway, I don't have hardern gears on my bridgeport, but if I went Perpheral, I definitely would of, epecially if I intended to sustain an average above 7500rpm for extended periods. Besides that, a scatter shield and balancing of the rotating assembly, maybe locked-pin rotors?

I have road-coursed drove mine and decided the average rpm I was at was 6500rpm(7mpg) but this is different for every course since more turns and fewer straight-aways will lower this average sustained rpm.

Anyway, I did actually have a stationary gear failure, for reasons I'm unsure. This was after one of the times right after rebuilding because I broke a carbon apex seal which broke for un-known reasons also, still had orginal height-thickness(which did NO Damage to the rotor housing! ). Its weird, because, I have one rotor with carbon seals with 23,000miles with less then a 1mm of materal missing and the other rotor broke one after 11,000miles with same thickness. Anyway, I re-assembled the engine and may of had the rear rotor not mesh straight on. No high rpm and no load above 4000rpm during the break-in period and gradually started vibrating. This resulted in a chewed up rotor gear/stationary gear, symtoms were vibration at anything above idle. A good reason I guess to move the e-shaft a little back and forth while tightening the tension bolts to be sure that everything is meshing correctly. THere was no visable damage the the gears before this all happened. The aftermath made me gasp that it could run with that many teeth mssing/disfigured. Anyway, thanks to Mike-P28, I got another rotor to get my bridgeport back on the road. Which has now gone about 28000miles on orginal purchased carbon seals on the street.

BRealistic

'Carbon apex seals'

Aren't those VERY expensive?

WackyRotary

Nope, they are infact cheaper then stock 12a steel seals.

BRealistic

Oh, my bad. I was confused. Is their a high rpm special apex seal, like ceramic? And I noticed Atkinsrotary has one-piece seals available- using this could you do a 'monster port' by removing the bridge from a bridgeport, instead of removing the water seal/ jacket? Without needing the bridge to hold in the corner seals, it seems possible?

REVHED

Carbon seals are used for high rpm engines.

The type of porting you're suggesting isn't possible as you still need the bridge for the corner seals to ride on. The advantage of a one piece seal is that you can cut a very large port with matched rotor housings without having to worry about the corner piece of the apex seal being dislodged.

BRealistic

Why are carbon seals cheaper? Do they damage the housings more?
And when using a special fit one-piece apex seal, what 'corner seals' are there that need to be lept in place with the bridge?

peejay

They're cheaper probably because they're cheaper to make. They're one piece (less machining) and they are not made of out a brew of cast iron that is chill hardened, they are a carbon impregnated aluminum.

The corner seals... you know, the little round seal between the side seals and the apex seals? Yeah. You need the bridge to hold those in. Also to keep the apex seal from sliding sideways.

mperformance

peejay, well I just ordered the stock looking ones from atkins, two piece, I think they are mazda apex(i). So there... I'm going for a budget racer. I still got your strut tower cable engine brace holding up the engine... heahhaha hey it works!!! I upgraded the whole thing with teflon (or something like it) solid engine mounts.

guys I'm still going 12a. The rules make the 1.2 a 2.4 and the class calls for cars with only 0-2500ccs of displacement so I'm legal...

wacky thanks for the advice very helpful.

680RWHP12A

i would use carbon apex seals only! on a p-port! who is making these housings? where you make the hole is critical as well as what size it is, as well as the port taper, as well as the exhaust port timing!!! there is only one companies p-port housings that work good! Rotary Reliability, talk to nick! i build motors but something that critical you better leave to a expert! also you need to use a 51 carb or elst the motor will not make optimum power!

mperformance

Thanks for the input 680RWHP12a, time is the issue here. I also do not live in the USA , but I do get my parts shipped quickly like in 1 day from US but the costs for a PP housing is just too much. Although I have no idea what nick at rotary reliability charges. Maybe you could tell me.

so you say carbon seals are the only way to go? I just need this engine for the upcoming race. It will get cracked open after the race. It's a 30minute race at most.

well like I said there are several problems I am finding as I go along in this project and the carb seems to be a big one. Now that you mentioned another would be be the port taper...I'm copying everything for my own personal use so I'm not revealing any secrets. Port timing can be found on the net as I already did and I might get some actual measurements from a Pported engine that was rebuilt a few months back.

BRealistic

What are high compression rotors? How much more than the 9.4 stock?
Compression ratio is a good point. The winning lemans 4 rotor hit its max output at only 9k rpm, but ran 10.0 rotors.

www.mymazdarotary.com/mazda_rotary_general/r26b/html/r26b_paper_html.htm+rotor+compression+ratio+mazda& hl=en&ie=UTF-8]4-rotor[/URL]

mperformance

12a high compression rotors?????! where can I find those?

Hyper4mance2k

iTrader: (40)

i'd do a half bridgy w/ street port on intake side , RB race exhaust port, with a 51 IDA. that way the car will still idle at 1000 rpm. and i've never heard of a PP idleing at anything below 1800 rpm normally around 2000 redlining at 10,ooo rpm