BlackSport0187

Considering the fact that many NAs can be bought for less than 2k why would a person invest in a S-AFC? I'm sure they'd rather stay "offensive" than blow that kind of cash.

Isaac

MikeL

Fine. Just don't tell people that the reason their car spews offensive odors is because they have no cats.

Tell them the truth, which is, that the car is not tuned properly.

SPDST3R

the question is - do we really need to get an S-AFC to tune our car (lean/rich)?

BlackSport0187

No, I won't tell them that, because I think rotary engines are by nature more offensive in odor than an equivalent piston engine. Some cars may run too rich and that may cause most of the smell, but I don't think that is what is causing all of it. Even if the culprit is a need to tune the car properly I don't think the only way to do so is by the use of an aftermarket controller. So, are you saying that when brand new all RX-7s were set to run too rich, if so then wouldn't that mean that RX-7s in stock form do make offensive odors? Then wouldn't opening up the exhaust on a stock RX-7 tend to make the smells more obvious?

Isaac

MikeL

Okay.

rxspeed87

when I put my header on my car I noticed a little bit of a smell.... it was real bad to start with but I put new plugs in, and bought a TPS (my car didn´t come with one) and also played with the variable resistor thingy and it seems that the smell has died down a bit... now if I put my hand RIGHT ON THE TIP I can smell it but other then that even if I let my car idle for a while it is not that bad.... and I have no cats....

but it was worse when things where not adjusted right and my plugs where bad



same thing that would happen on my 71 camaro when things where not adjusted right

scathcart

]

By nature more offensive? Incorrect. How about we get things straight. Cars are not about what a person thinks, its about facts.

FACT: If any engine stinks, its b/c its running too rich. It will often smell of rotten eggs

FACT: Catalytic convertors help allow the exhuast to keep burning before it heads out the tailpipes, thus killing how rich the fuel is (and thus flames, and smell).

FACT: All RX-7's, and most every other car, were set from the factory to run rich as to give more longevity to the engines. Engines don't last near as long tuned on the edge of detonation, so they are set rich from the factory.

FACT: Opening up the exhaust on an RX-7 doesn't allow the fuel mixture to keep burning as well, thus, more unburnt fuel remains in the fumes. This is what allows "flames" and the smell. Tuning the car to avoid the smell will result in more power, and it will be tuned better.

FACT: If your car stinks, its running too rich. Deal with it: You need to tune it. Rotaries are tuned rich from the factories, usually more-so than other cars due to their tendency to detonate and blow motors. However, its not the nature of the rotary to stink, its the nature of how they are factory tuned.

Now, from now on, if you don't know the facts, keep your mouth shut, b/c you obviously don't.

"Rotaries stink, its just the way they are".... Nothing more than utter ignorance.

Felix Wankel

You write some of the best replies ever.

MikeL

Thanks man!

Here's the deal...,

BlackSport0187's posts only matter if I care and, I don't give a ****.

boostmotorsport

My T2(W/out cats) at idle doesnt smell bad but does make eyes water, I mean sting!.

Felix Wankel

Lean it out with your S-AFC.

qwerty

You know, I found this forum by chance looking for parts & actually found a few good tips by using the search engine, but 99% of this forum is pure garbage. Over 193000 posts & ~192900 sound like a bunch of high school kids pointless chatter.
You've got someone like MikeL who has a clue what he is talking about & a bunch of people who don't flicking him ****. No wonder there are 193K posts here. If you're car smells w/o cats the solution is simple, put them back on. If you don't know how to keep the thing in tune, why are you messing with it in the first place? I've bought too many dirt cheap RX7's & see too many perfectly good rex's in junk yards because some shade tree mechanic thinks he is smarter than the engineers at Mazda.

Turblown

iTrader: (12)

wow thanks guys, damn i can now get rid of that smell! sweet, i always wondered why those old muscle cars never stank.....

rx_7_driver

cats r for tree huggers

Scott 89t2

I have a cat and leaned out 8% at idle (any more and it gets rougher) and it sill stinks a little bit but not when I still had the air pump and ACV and no AFC.

Zach McAfee

I don't know why I'm fighting back. I could save myself the trouble ignore people like Mike does.

Anyways, Isaac, I consider a "tuner" to be a person who has alot of experience with RX-7s, has enough money to try different upgrades and buy the best upgrades, and knows how to adjust their cars for optimal performance.

Why do I know MikeL is a tuner? He has a 400 RWHP 2nd gen, he has gone through a couple different engines, he obviously has enough money to support his RX-7 passion, he has more than one RX-7, he has friends who have bad *** 2nd gens, and he races and TUNES his car. He also has a website so you can see for yourself, which is how I know.

I think I'll just say "OK."

What was this thread about again?

Zach McAfee

I'd also like to throw this in.
I come to the gen specific/ performance forums to learn something. Rarely do I get on a tech subject and begin to argue with no end. The lounge is here for bickering, threats, ect.
At the same time it is also OK to argue your opinion on a tech subject. It's a grey line, and it's your call.

Thanks for listening to me vent.

GuidoCat

I did a little tuning myself. I mean my mufflers rusted off. And now my car stinks like a fat woman in a mini van with no air condition on a hot day. I was thinking about instead of tuning it just put some pipes going straight back and putting some ignitors on the end. That should fix it.

BlackSport0187

Lol. I always find it amusing when guys like you rant and rave about the facts, and how they are such rotary masterminds. Calm down, no one will think you are a better person by knowing every little detail and spending all day on the internet.

Now back to the subject, everyone knows that the Series 1 RX-7s came with thermal reactors and were tuned to run really rich because it helped the operation of the reactor. Was this for emissions reasons or to avoid detonation? Obviously the former, because on the Series 2 cars the reactor was eliminated and was replaced with a series of catalytic converters. It is well documented that the fuel mixture was then adjusted to not run as rich (no reactor) and a resulting boost in fuel economy was achieved. To avoid detonation or to meet emissions requirements, probably a little of both? So, like you said if you don't know all the facts keep your mouth shut. The whole truth and nothing but the truth bro.

As you stated, rotaries are tuned rich from the factory, more so than other engines. Could this be, as history shows, that rotaries are not as clean running as piston engines (in some respects) and that is why they have to run rich to pass emissions? Wouldn't that mean that in stock form the fuel settings on a rotary are set to run more rich than others (we already knew that), thus they create more of a smell than others, and the smell is amplified more so when the exhaust is opened than on others? Huh, so one might say that rotaries are "by nature" a more stinky engine in stock form? I think I proved my point.

Isaac

BlackSport0187

Forgive me if I'm wrong, but isn't this forum for talking to other RX-7 owners and sharing ideas and knowledge? If you have a problem with that go back to looking for parts.

Oh, and one more thing, how can opening up the exhaust on a car cause it to be sent to a junk yard? What adverse effects can it possibly cause? There is no need to lean out the fuel mixture as you claim, because let's face it the engine will probably last longer via the use of a relatively safe factory settting.

Isaac

BlackSport0187

I consider a tuner to be anyone who can work on cars fairly well and knows from experience how to correctly modify a car. Do I fall into that category at this time? No, but I am learning and someday I might. I'm sure MikeL was in the process of learning when he was going through those engines. Since when does a person have to have a large bankroll to be considered a tuner, what about the guy who saves his $75-a-week paychecks for months to buy an Apexi S-AFC? Would you consider him to be a tuner? Or is he not rich enough to be a tuner?

Isaac

eViLRotor

iTrader: (2)

This is an interesting argument!

I have a 3 inch custom exhaust, no emissions!

My car smells like fuel at idle = running too rich = needs leaning out with the Wolf3d = not stinky just because its a wankel.

Just MO...

BLUE TII

iTrader: (9)

MikeL and Felix Wankel- you guys know your stuff, but sometimes you get stuck in a mindset.

Haltech manual chapter 7 "cold starting and running" - read it.

Your car NEEDS to run quite rich on start up and cold running condition in order to combat manifold whetting.

Did you go in and Zero out the factory loaded cold cranking and fuel correction vs coolant temp maps?

A modern car w/ close coupled cat or pre-cat like our cars gets that cat up to temp pretty fast. I think the smell of our catless cars on start up could arouse suspicion since it smells like raw fuel, not that sweet-ish sulfur-ish smell cat equiped cars have.

Runnig in close loop- yes, it should not smell. Ian

Aaron Cake

iTrader: (1)

I have a dead cat, running 4 TII injectors and an FD fuel pump. My car doesn't stink at idle because I took the 30 seconds to tune S-AFC at idle. Not hard.

However, most FCs will run rich at idle due to various problems (leaky injectors mostly), and the vast majority of them have a dead or flaky ACV, so....you get the stink and dead cats. Keep the car running like it was designed to (clean those injectors, check that ACV, etc.) and it won't smell.

My 3 cents...

BlackSport0187

I can respect your opinion. To each his own.

Keep those rotors spinning,
Isaac