"My objective is ~500RWHP on PUMP, ~650RWHP on C16...in a daily driver, decent enough response/spool to track it on a larger road course (i.e. summit point)."

congrats to all on what has turned into an excellent thread...

how about 650 instead of 500 from your daily driver?

actually given the rotary's inclination to E flex above 600 how about 600 in a daily driver?

all it takes is the addition of some alcohol to your pumpgas. before i get into it please do let me say that it is your project and whatever you want to do or not do is purely up to you.

that said....

it is going to take lots of work to fixture all the correct systems on your FD to make 500. it makes no sense to me to exclude another system that would go a long way to making more power and reliablility. there is nothing more fundamental than the fuel you run through the motor. fuel quality is more important to the rotary than a piston engine.

since you mention road racing (good for you, that's what the FD was built for) it might be that you (correctly) are assuming that most of the alcohol sustems don't work very well on a road course. and you would be correct.

the old school systems work off pump speed and boost. the problem is boost can vary very quickly as you are on and off the gas in a corner whereas the pump can't keep up resulting in uneven alcohol delivery.

new school alcohol works w a constant pressure from the pump, fuel injector-like solenoids and a X Y grid w boost and rpm. you have immediate and accurate control of the alcohol. no different than how your base fuel is controlled.

what concerns me w re to a 500 hp pump only deal is what happens when you get a tank of marginal gas? unlike your viper.... it will be good-by motor.

w the alcohol you have lots of help. in addition, there are various safeguards built into the system. for instance if your AFRs take off due to bad gas your timing can be jerked, the WG can open or you can even do an ignition cut.

alcohol is magic. after a dyno run you can put your hand on the UIM and it will be COLD. real cold. i run a 4 gallon fule cell in spare tire well and the whole thing is seamless. no knock, and you can run all the boost you want. any time.

check out my most recent FJO install in the AI section for details.

https://www.rx7club.com/auxiliary-injection-173/fjo-2nd-gen-ai-interfacing-wide-band-install-tune-thread-702559/

good luck,

howard coleman

 

Howard,

I appreciate your comments and points regarding AI*

Let's start with race fuel/C16...The reason I even stress PUMP gas as much as I do is b/c where I'm from true pump gas bragging rights/performance is big. Also, even though I have a huge drum of C16 sitting in my garage for "call-outs" (hehe), it's highly impractical to run $11.00 a gallon race fuel in a gaz guzzling sportscar. On a race in my supra a few months ago (has 6 750cc inj + bigger fuel pump) I filled up with 10 gallons of race fuel = $110. The race location was 55 miles ~an hour away from my house. I filled up at home, burned almost 1/3 my fuel just getting there, 1/3rd on the races and series of highway roll-ons, and 1/3rd on my way home...as I rolled up to my driveway it was flat on E. A $110 up in smoke in just a couple of hours of driving...that my friend is a JOKE. So, what rotaries can theoritically do on C16 I'm not even concerned with as I (like most people) won't be running it 99% of the time as I get caught off gaurd in a street confrontation.

As far as Alcohol Injection... There are a few reasons I didn't really consider it. First, i have personally witnessed many AI-related engine failures on turbo four-banger cars such as EVO's. Either the system failed and the engine went with it, or it wasn't installed properly from the get-go, or the tuning behind it was too difficult for the techs making for doggy results at best, the ****-poor injection during constant on-off throttle senerio's such as road racing (as u mention), etc, etc...lastly, with 10 cylinders and 8 liters of displ. I guess I had just been spoiled with pump fuel HP numbers as there are many boosted Viper guys running WAY OVER 1000RWHP on straight 93.oct pump. And with a forged Viper motor if you start hearing some detonation (which is very rare)...no problem, she'll live, LOL.

I figured tune the final set-up at 91oct. pump gas so should I ever get a less than ideal tank of 93oct which is all they sell around me I'll be fine...more margin of safety against "a bad tank of fuel." So essentially, for reliability's sake, I want to make ~500RWHP on ****-water 91oct* not even 93!

I WILL say though...i did take quite some time to carefully read through your entire alcohol thread with your person car/experiments. Where no matter how much higher you were going on the boost your EGT's would stay the same (or even go lower! lol) And you virtually couldn't get the thing to detonate if you wanted to. Very interesting and encouraging results which show me that perhaps AI benefit a rotary motor design MUCH more so than even piston motors.

**It appears to me that with rotary's, the most important thing is avoiding detonation at any cost. Basically unlike a piston motor, ANY detonation at all spells engine failure. And because of their nature, rotary's run much hotter to boot. A bad combination when u consider the previous statement i just made.

So HERE IS MY ROUGH SET-UP considering all that has been said...

...with regarding to tuning...I can already see that I'm going to be a lot more to the rich-side to help with the combustion-chamber cooling. Also, pull MAD timing. All while keeping IAT's down as low as possible with a big front mount and an efficient single turbo (GT40R). A good 'street race port' + slightly extended redline (~9K)to go with all i just mentioned could possibly do the trick to crack that magic 500rwhp figure. (on pump) Higher revs help keep cylinder pressure down (when keeping HP a constant). Which also go to helping to elimate detonation. And last, but definitely not least, throw in a set NRS's latest 'gray material' ceramic apex seals and WALA, that should do it (and "should" be able to run a lot higher than 15PSI on 91 reliably. like~18-19psi.) Either that or i'll be holding a bunch of rotary scrap metal on the side of the road saying to myself "i guess my calculations were incorrect"


So Howard, and experienced rotary heads, reading thru my novel & raw set-up ideas here....are my calculations correct? Or will I be sitting on the side of the road with an eccentric shaft up my butt* ..lol Knowledgable feedback highly appreciated.

 

vipergtsr your in maryland and not to far from a very good rx7 tuner Ray wilson of pfsupercars in frederick and he also sells and tunes cars with meth injection might want to give him a call. check out ErnieT 's car and see what he does

hey turboedrx7 you werent the only 7 at college park and my car will be back in 2 weeks! now im the only 7 going?

 

Those apex-seals would be a cool upgrade, but I wouldn't trust them to consistently provide you "high-boost" safety.

 

I just don't see it happening honestly with straight 91 or let alone 93. While a couple people can do it, its far from the norm around here. I'm guessing it would no longer be a street port, but probably a bridge if not a peripheral engine. 400rwhp to 450rwhp on pump is probably a more realistic goal. Of course, I'm talking without the aid of AI. Just my .02, CJ

 

This is not a question of "if" it can be done....because it really isn't that hard to make 500 on pump gas alone. To me the question is why? Why take such a risk for "bragging rights"? Why would you set out to build a time bomb? Why would you want to build a $15K set up that's life relies on a sticker that says "93 oct" on it? Pump gas is sooo unreliable and unstable especially @ the boost levels needed to to make 500rwhp.
I love to prove people wrong, make a stand, prove a point or do what someone tells me cant be done but I'm also trying to go about it in an intelligent way as well.
And I don't believe pump gas @ those levels is "intelligent". My $0.02 AI ftw!

-J

 

Since all this stuff is kinda new to me what kinda boost are we talking about to make 500whp?
The eggnog has finally soaked in!

 

Hmm, I would say 14-16 psi?

 

For 500RWHP, I would say a GT40R kit would have to be at ~17-18PSI...on a half-bridge or big street port.


HOWEVER, it appears that this thread is going to die pretty soon becuase the more I research the topic and feedback i recieve...it simply appears 500rwhp won't be "reliable" for extended periods of street use...anyway you hack it. And being I'm a road racer at heart, it's even less practical doing hot laps around our local 2.2mile road course/race track.

My stipulation was to see an 500RWHP, but also be reliable at that level on the street as a daily driver. It's appears AI is the way to go with these rotary motors...they seem to benefit the design of a rotary far more than piston engine making a 13B a very formidable opponent when running with AI. I have to thanks several of you guys for making the suggests about it, particularly Howard C. for his in-depth thread on the subject matter on the AI section. Nice work datalogging the results for us all to see...amazing how night-and-day the benefit of AI are to these motors.


Moving on......

I'll probably start a seperate thread on this, but now I have even more questions about AI...for you guys other running the stuff. How precise is the tuning behind it and can it be effectively used in a corner-to-corner road race situation. Where part trottle/on-and-off throttle is paramount*

And what boost levels are safe to run to with 2mm seals on AI...for every day reliable use?

Being that in my circle, i'd be "cheating" using AI now...the new goal is 550RWHP on pump gas & AI. I think a GT40R kit will require ~22PSI to achieve this power on a ported 13B. So....is THAT new goal using AI practically achievable? Is 22PSI as an everyday street boost setting (daily driver) and 550RWHP completely practical using AI?? Any eccentric shaft, 2mm seal, or other weak link i need to be concern with in the motor at an everyday 550rwhp...?? Thanks.

 

Thats funny they've been in testing on the same motor for over a year with over 50lbs of boost. Is that enough? The same car just went 6.97@197mph
And you can get away with straight water injection without the meth. The water has better cooling properties and acts as a displacment adder which will give you even more power. Not to mention, you will have NO carbon build up.

 

Ernie, do you run water injection? Have you considered alcohol/water inj 50/50 mix. Also, r u running the NRS seals? A GT42R like urs at ~39+lbs should do ~800RWHP! And those seals can easily handle that.

 

You could easily make 500whp on pump gas...












With something other than a rotary int here. j/k. all jokes aside, with how pissy this motor is with detonation (See-Time bomb) I would not even bother pushing it that hard!

 

AS far as your question for how precise you can tune AI check out http://www.fjoracing.com/products/waterinjection/

I can't offer real time usage as I haven't tried this system yet but I intend to use this setup driven by the haltech e8 along with the autronic 500r. Its fully mappable like a fuel injector.

Unlike yourself I will not be anywhere near 500rwhp as my turbo setup only netted me 410rwhp at 15psi. (Turbonetics T04B 60-1 .96a/r etc) Increasing the boost did nothing but increase bottom end power/torque.

All the best in your build.

Ian

 

We were in the Speedtech tent with the black RHD FD and red FC . We ran brackets because couldn't make in time on Saturday qualifiying. So yes indeed Ari ran street and Karl ran Quick 16 (in which he won)

 

You missed my point (which is very basic) but should be clarified for someone unfamiliar with rotary-engines.

Having stronger apex-seals doesn't (in it's own right) give you the ability to safely turn up the boost from a pump-gas safe level of around 15psi to a higher PSI... Just because the apex-seals can withstand detonation doesn't mean you should subject them to it. And (of course) detonation can do damage to more than just apex-seals.

 

Hey Viper, I think you should seriously consider the benefits of a 20B-swap.

 

You said withstand boost, not detonation. Nothing will withstand that. Sounds like your in need of a good tuner.

 

Yes to all your questions...NRS seals are ordered for a fresh motor for this coming season. And yes I run water/meth injection. This year will be strictly water though as NHRA doesn't allow the meth injection in the street class.
I could only run 32lbs of boost with the bridgeport cause I was out of fuel injector. This year 2 more injectors will be added with the NRS seals and straight water injection. Should be close to 800ish. Motor is the easy part. Drivetrain, on the other hand is a different story, lol...

 

Fixed for clarity.

 

Let me introduce you to my friend/tuner 'FISH'!!!!
Anyone can tune a piano but not everyone can tunafish!
I'm so lucky my tuna comes in a can.
Still stuffering from the side effects of corn fuel!!!

 

Shhhhhhhhh!
Displacement increase is only a tap away.

 

Ahhh... The implication was unclear I suppose.

 

For pump gas numbers there's a benefit there...but for me considering AI technology now, a 13B is a FAR superior motor of for an FD RX7 looking for no more than ~550RWHP. It's lighter, more compact, far more cost effective as its the OEM motor, and easily capable of my intended ~550RWHP. With AI it's all upside over a 20B as I see it. It's only worth looking into a 20B for HP numbers well over 800rwhp IMO...(even then I've heard of reliability issues related to their longer e-shafts)

 

here's an attaboy to Viper GTSR on the 13B-20B comparo.

prior to AI, 13Bs were pretty much stuck around low 400s on the street. a 20B did provide an major performance margin.

w AI you can run low 500s if properly fixtured. if you have driven an FD w 500 rwhp you will know that ponies above mid 500s are a little nutso. the car is pretty much out of control w 500+hp.

at that point you ask yourself.... do i need a 20B w another 200rw?

the answer is of course yes if you drag race, seriously drag race... as in $5000-10,000 transmissions etc.

if you road race/street race.... no you don't need more than 500 or thereabouts.

this is not to say you shouldn't do it.. just the returns of another 200+ hp from a 20B are declining in the real world. there a people that are on, or have been on this board that have built 600+ hp street monsters and have been bummed to the point of selling their FDs as they just go sideways at any speed.

550+ street FD = drifting anytime you want.

there is a sweet spot where you can pretty much run w anything and still live happily w your car. while that spot varies for each of us, the top of it is probably mid 500s.

13B + AI = 20B without all the hassles.

hc

 

We put down 575 RWHP at 14 lbs of boost with a 20B. I would say its well worth it if you have the money.