Can NA/TURBO FC's be Semi-Reliable & Produce Low-End Torque?

[bl4rg]

I am pondering purchasing a rotary but I am plagued by a few very cruicial questions.

1) CAN THE FC BE SEMI-RELIABLE?
I am almost 100% sure that expensive rebuilds are inevidable with the series of engines that come in the FC chassis. But is there a way to tune them to become more reliable?

2) CAN I GET LOW-END TORQUE WITH A NA ROTARY?
My father is an engineer who was around when the rotary engine was pantented and sold to GM and Mazda back in the 70's. He explained to me that one of the major problems with the rotary engine was that it is hard for it to produce low-end torque which is cruicial for auto-x/drifting. He also explained to me this is part of the reason why GM bought the patent, deemed it as a waste of money and basically canned the idea and never looked back. (other than poor gas mileage) Mazda has spent years trying to perfect the rotary engine, only to have created a high maintenance problematic engine.
I am definitely leaning towards a NA engine. Due to the fact that turbo's have such higher maintenance, and a whole other series of parts that can fail.

3) ARE TURBO ROTARY'S THE ONLY WAY TO PRODUCE REAL POWER?
We all know that turbo rotarys are nightmares if tuned improperly, so is a higher reving NA (if possible) rotary a viable solution?


I am selling a Integra show vehicle right now to purchase a FR vehicle for drift/auto-x use. 240SX's are always a possibility, it just seems like they would cost a fortune to swap out the engine for the prefered SR or CA, LSD, and suspension. Also due to lack of parts living here in the dead center of Canada (204 WPG BABY w00000) it would end up costing me a fortune. A 86 is a VERY viable solution to my problems, although finding one is the major problem. I could very well buy one off a yuppie with rust all over it and cut my own sheet metal and do all the body work but like I said, its all about finding one. The last generation MR2 (not MR-S.... love those togue monsters) is a beautiful vehicle but, most likely not in my price range. I hear lots of drifters knocking them for obvious reasons (MR). Dont forget the drift bible though, the king WAS drifing a MR2 in it. (with some difficulty I might add) I want a vehicle that I can put elbow grease into the engine/suspension, drive like a madman and beat the exterior like a redheaded stepchild only to go to scrap yards, cut, paint, bondo, and create my own fiberglass. This is all off topic though. Importing a 1990 cefiro is also a viable solution, but a rather expensive one. As I am working with a limited budget. I WANT TO DRIVE HARD THIS SUMMER AND I NEED YOUR ADVICE!!! DO PEOPLE HAVE FC's WITH MINIMAL PROBLEMS? CAN THEY PRODUCE LOW-END TORQUE? CAN I GET HP WITH A NA???



THANK YOU AND I HOPE THIS STARTS A INTERESTING THREAD

[malcolm]

1) CAN THE FC BE SEMI-RELIABLE?

yes. it all depends on your engine builder.

2) CAN I GET LOW-END TORQUE WITH A NA ROTARY?

not a lot... but because there are so few moving parts, it's not too difficult to rev the piss out of them to make your power that way

Mazda has spent years trying to perfect the rotary engine, only to have created a high maintenance problematic engine.

so if you know this, why are you asking these questions? You're plain wrong, I might add. Look at the RX8. Good gas mileage, and good power... all quite reliable. It's uneducated people who spread rumours based on people that know very little about rotaries having obvious failures when they try to make lots of power from them, without doing their research.

3) ARE TURBO ROTARY'S THE ONLY WAY TO PRODUCE REAL POWER?
We all know that turbo rotarys are nightmares if tuned improperly, so is a higher reving NA (if possible) rotary a viable solution?

You can make about 320 bhp max with a N/A rotary. That's with a either a huge bridgeport, or a peri-port. Both are bad for gas mileage, bad emissions, and don't make ANY power below about 7000 rpm or so.

Turbos aren't the only way to make power, but they're the most sensible way. An FC, with 10-12 psi of boost, BIG intercooler, slightly bigger injectors, revs kept below 7500 rpm... you'll have an engine that will last a fair while. It will produce about 300 bhp, and won't be near as stressed as an N/A rotary. With hard driving, I'd suggest a rebuild every two years or less, if you can afford it.

[bl4rg]

Hmm, links I need links. I know the RENESIS has been reliable up to this point. It has also not been really tuned much up to this point as well, and it doesnt have the low-end torque either. Im not asking info on how to build some MONSTER DRAG 300+HP rotary. I want a good torquey ride and around 250hp Naturally Aspirated. Can this be done without blowing engines left and right? I was told by a race engineer that has built a open wheel racecar in the 70's when the rotary was patented, that rotarys have some serious issues to them. That is why GM bought the rights to use the patent, but a GM rotary was never produced. I have also heard rumours that if massaged just right, the series of engines that come in the FC can be reliable. BTW this whole thread involves the FC, no other series.

P.S Can someone speak from experience and not heresay and/or provide links to builds/mod lists/dyno charts etc.

Thank you but instead of flaming, just help me with my questions and stop treating me like a dummy.

[malcolm]

Can someone speak from experience

I do speak from experience. I raced a turbo FC for over a year, and learned a lot from it.

For a turbo with 250 bhp, what you want is to keep your porting stock. Raise the boost to about 9 psi. Still, I advise going with a big intercooler. Helps with power AND safety. You can't go wrong. Don't block off the entire rad, but definitely go with a front mount that's bigger than the stock intercooler.

For normally aspirated, you're going to need to do some porting, which will lower your bottom end. A mild bridgeport would do the trick for you, but you will still lose a lot of power down low.

As far as good info goes, I'd suggest racing-beat.

I was told by a race engineer that has built a open wheel racecar in the 70's when the rotary was patented

ooooh, the 70's. you do realize that mazda has come a LONG way since then, just like how in the 70's they didn't understand or implement ground effects on racing cars, nor were turbos well understood, etc, etc. I have two friends that put well over 150k miles on their FC's.

Hmm, links I need links.

http://www.google.com

there you go. that will guide you to more info than anyone on here could suggest. look up RX7 sites, mazda sites, anything you can get your hands on.

Also, the rotary was patented LONG before GM or Mazda even heard of it. The famed german engineer, Wankel, worked for NSU, used the rotary in one or two models, and they sold the patent from there.

Thank you but instead of flaming, just help me with my questions and stop treating me like a dummy.

perhaps instead of propagating misinformation, just ask simple questions without letting other peoples anti-rotary bias show through.

[SidewaysGts]

The rotary is actually pretty reliable- its when you come to that rebuild point do you start to encoutner problems.

Maitenence and work on them is over hyped and played up as well, bayond basic know how, the only 2 things crucial to keep in mind are to change the oil about 2000-2500 miles using mineral oil (synthetic leaves carbon build ups in the housing i believe), and avoid over heating like youd avoid a sledge hammer after your balls. Over heating is bad, and since theyre hot engines to begin with- thisi s why many people run into problems.

As for the low end torque and autox and drifting... well, i just point to the miata. Owners of the auto x- and the 86 for drifting. If you dont make low end power, dont stay in the low end.. you have a transmision with gears for a reason, use em.

added: btw tsuchiya never really had trouble drifting that mr, dont you find it odd how he says what NOT TO DO everytime before he makes that mistake? its supposed to be educational, he warns you what not to do- then shows what happens when you do, same goes for when hes in the mr2.

[bl4rg]

Malcolm you have a bad attitude,

'That is why GM bought the rights to use the patent, but a GM rotary was never produced.'

I am fully aware Wankel patented the rotary. Then GM and Mazda paid to use the patent. Like I said. GM saw no future in the engine due to numerous problems so their concept car never made it to production. Mazda saw a possible future in it for the JDM so they put lots of R N D into it. Dont pop the google thing on me either, I posted on this site in the hopes of someone posting a link to THEIR tuned NA/Turbo FC and THEIR comments on the reliability factor but clearly you havent produced a link. So why dont u stop flaming and actually help someone out.

As far as anti-rotary bias, its a known fact that FC/FD rotary engines when boosted/driven hard need to be rebuilt quite often if they are not tuned right. This is not propaganda, this is fact. Im not trying to be a asshole here, I just want specs/charts/pics etc.. REAL INFO..

DEFINITELY NOT
"I do speak from experience. I raced a turbo FC for over a year, and learned a lot from it.

For a turbo with 250 bhp, what you want is to keep your porting stock. Raise the boost to about 9 psi. Still, I advise going with a big intercooler. Helps with power AND safety. You can't go wrong. Don't block off the entire rad, but definitely go with a front mount that's bigger than the stock intercooler."

btw: by saying the king had some difficulty drifting the MR , I meant that it was basically the only unintentional fux-up on a drift in the whole flick. I believe the narrators comments were something along the line of 'even the king makes mistakes sometimes'...

Be a tree hugger and if you dont have anything nice to say dont say it all....

[bl4rg]

btw thx for info SidewaysGTS..

[theflatlander]

1. FCs are generally reliable as long as they are taken care. The average n/a will last well over 200k miles and Tii average about 150k miles. And yes you can mod them to be more reliable,bigger radiator, thermal pellet bypass, and pre-mix are a few.
2.if your looking for low-end torque in a rotary get a 20b, but with the 6-port 13b and add lets say a stock Tii turbo setup it'll defiantly add power down low (spool at around 2k rpms even less with port work done)and if your thinking of buying an rx-7 dont bother looking for good gas milage. FCs aren't that high maintenace compared to FDs.
3.How much power is real power? I'm currently working on turboing my n/a and will be looking at 250-270 whp at 10psi which will be jsut fine for me until i decide to throw my 13bt half-bridge into the engine bay which i'll be looking at an excess of 450whp which should make things interesting.
ANd yes there are tons of Fc owners that dont have problems, i've owned mine for over 2 yrs and haven't had any complaint except for the owner before me not taking care of the motor and have it upchuck an apex seal later. But that led to new and better things for the car.

[SidewaysGts]

What accidently happened in the mr

Added: btw, ive never seen the "Average" na fc run 200k with the "Average" tii running 150, more like 100 for the tii and 140-150 for the na

[Hollywood]

the NA motors will last a while, I had over 250K miles on my NA when it blew and I beat on that car every day.
you can get more power out of an NA, I have a friend who slapped a holley 4 barrel carb on his with a header, no internal work to the motor, that car moves real good, its a good drift car.
I do know guys that drive bridge ported motors every day on the street, so you could always go that rout.
as for torque, I have never found it a problem in any of my Rx7s, I do own a corvette that makes ofer 450ft/lbs. I have actualy beat my vette on the hwy while driving my TII. the rotoary revs much faster.
if you are worried about reliability, just buy a brand new mazda reman, they come with a 2 year warranty
but go drive one, and you will under stand!

[Jeff Abbott]

I am a big fan of the rotary. I have had an 80,86 and 87. My father had a turbo FC. I beat the s*** out of all of them. They all ran very well. Just change the oil every 3k. Dino oil, they use it and because synth leaves a deposit as mentioned above.
As for a rebuild(this is from experience) I did one with my father on the turbo engine. I would def rather rebuild a rotary than a piston engine. It was a pretty simple task just following a manual and making sure all the clearences were correct. I have never rebuilt a piston engine though. I am obviously biased. I love the wankle and so do many others. A lot of people say its a poor engine because they just dont understand it and/or never worked on one.
My .02
-Jeff

[pez2k]

If you have a limitless budget, apparently RE-Amemiya and Greddy built a custom '24A' quad-rotor from two old 12A's, which was making rumouredly around 700bhp N/A.Wouldn't surprise me, with the crazy RE-Am/Greddy series of Mazdas (AWD FC, check, 20B AZ-1, check...).

[malcolm]

Can someone speak from experience and not heresay and/or provide links to builds/mod lists/dyno charts etc.

if you just want links, then don't put an OR in your question. You asked for someone to speak from experience, and I did. Don't like it? Don't take it. I am not forcing it on you.

Besides, if you are planning to build your engine with info found on the internet, don't expect your engine to last long. A simple dyno sheet won't prove a thing (I am sure you've heard of the tricks pulled with putting heaters next to temperature probes, then plotting the "corrected" power outputs, which are on the order of 30-50 whp higher. word to the wise: if your engine builder prints you out a sheet, ask for the uncorrected plot. If it differs by more than a few bhp, then you know they're pulling a fast one on you). A lot of people can provide legitimate-sounding advice with seemingly logical evidence, yet they can be totally wrong.

I've given you all the info I have. I have no more, as I didn't do the engine work myself. Also, I could make a page, and then give you a link, but that wouldn't give you any added info. What I told you was supposed to be a **general outline** of what you could expect, based on my experience, and the experience of some of my friends who have raced rotaries (N/A and Turbo). If you want a detailed technical review of every little thing, then why are you at a general drifting site? Wouldn't it make more sense to email a few engine builders, or perhaps go to a rotary-specific forum to ask people with greater knowledge than drifting.com?

As far as anti-rotary bias, its a known fact that FC/FD rotary engines when boosted/driven hard need to be rebuilt quite often if they are not tuned right. This is not propaganda, this is fact.

nope. propaganda. ANY engine that is "boosted/driven hard" as you say needs to be rebuilt quite often, not just rotaries. At about 280 bhp (we never had it on a dyno), our engine went for two full seasons (someone raced it for a season after we sold it) with no problems. That's under full racing conditions, which is torture compared to the street with a bit of track/drifting use on the side.


Attitude? I would say that you have more attitude/incorrect info than I do. Let me go over a few of your quotes:

Mazda has spent years trying to perfect the rotary engine, only to have created a high maintenance problematic engine.

in the 70's when the rotary was patented,

followed by:

I am fully aware Wankel patented the rotary

so which is it???

P.S Can someone speak from experience and not heresay

you rudely blow me off, inferring that I am just spreading hearsay.

Finally....

Thank you but instead of flaming, just help me with my questions and stop treating me like a dummy.

At that point, I didn't flame you. You said the rotary was problematic. I disagreed, and gave my evidence. If anything, you are the flamer, with a fair amount of attitude.

Also, what I said about uneducated people was not directed solely at you. Read it over. Too many people pass off cars/engines/parts because one or two people have claimed that they had problems. I've seen many a V8 explode, but I don't go around saying that V8's are prone to explosion, because I know there are always mitigating factors behind their demise.

I did answer your questions, as I saw fit. I didn't know you wanted a detailed technical review, so I just gave a general outline from my experience.

*When you ask a general question, expect a general answer.*

[twcfc3s]

BoooOOOOOYaaaAAAAh!!!

[Jeff Abbott]

Malcolm is right. In General hahaha.
I want a turbo'ed 20B in my car
-Jeff