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-   -   How can I tell if I'm running rich without a wideband? (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/how-can-i-tell-if-im-running-rich-without-wideband-683745/)

MmSadda 08-28-07 03:57 PM

How can I tell if I'm running rich without a wideband?
 
Just like the title says- how can I tell if I'm running rich without a wideband? I just had my engine rebuilt a year ago, and have yet to change the sparkplugs. I know I can look at those...
I can shoot flames out the exhaust; if I recall correctly, that means I'm running rich. However, I do not have catalytics.

Anyhow, is there a definite way I can tell if I'm running rich, and if I should get a wideband?

speaking of which, how much does a wideband cost? is it worth the price? and can I get one, or is there even a point, without going to a standalone fuel management system?

Sideways7 08-28-07 04:00 PM

You can get a narrowband a/f meter. It will tell you if you are rich.
As for getting the wideband, its really nto much use unless you have something to tune the fuel curve with.

stylEmon 08-28-07 04:48 PM

if you are running fat, your car will bog down down low, in the lower gears.

88t2romad 08-28-07 04:53 PM

its a fairly crude method, but how many miles are you getting per tank?

The Shaolin 08-28-07 04:54 PM

You're probably running pretty rich, but does it matter either way if you don't plan on tuning it?

Pick up a wideband and an SAFC, at least. Easiest and cheapest way to effectively tune, imo.

PvillKnight7 08-28-07 04:57 PM

PLX m300 $300

phoenix7 08-28-07 05:00 PM

fastest way? take it to a dyno.

Best way? get a fuel controller and THEN take it to a dyno and have it tuned.

COOLEST way? get a wideband, get a fuel controller, learn how to tune and do it yourself.

PvillKnight7 08-28-07 05:05 PM


Originally Posted by phoenix7 (Post 7280741)
COOLEST way? get a wideband, get a fuel controller, learn how to tune and do it yourself.

+1

u want to be cool dont u...DONT U??

MmSadda 08-28-07 05:34 PM

How much will a wideband and fuel controller run me? is it worth doing on an n/a, or should I stop spending on this car, and just start putting money in the bank for the eventual tII or FD?

cptpain 08-28-07 05:36 PM


Originally Posted by MmSadda (Post 7280521)
Just like the title says- how can I tell if I'm running rich without a wideband? I just had my engine rebuilt a year ago, and have yet to change the sparkplugs. I know I can look at those...
I can shoot flames out the exhaust; if I recall correctly, that means I'm running rich. However, I do not have catalytics.

Anyhow, is there a definite way I can tell if I'm running rich, and if I should get a wideband?

speaking of which, how much does a wideband cost? is it worth the price? and can I get one, or is there even a point, without going to a standalone fuel management system?

if you can smell your exhaust when sitting in the car with the windows down

Sideways7 08-28-07 05:37 PM

Honestly, a wideband isn't really worth it for an NA unless you are really trying to sqeeze out every last HP. An s-afc is, however. It can help your gas mileage as well as get you more HP with a good tune.

phoenix7 08-28-07 06:06 PM

and both can be removed later and reused in a TII or FD. ;)

Like it was said above: If you want to squeeze the most hp out of the NA and/or improve mpg then this is the way to go. You can always upgrade the parts that ccan be transfered into a TII so you don't LOSE your money.

make the choice now though. If you don't plan on keeping the NA then don't bother. If you see yourself with this car over the next several years then start putting money into it.

MmSadda 08-29-07 05:13 PM

Here's my story:
I had the engine rebuild less than a year ago, and a transmission swapped in. I bought the car for fun, and intend to keep using it as a daily driver in all seasons except winter- it'll probably get driven heavily for 8 or 9 months out of the year.
Like I said, I've already dropped a significant chunk of money in the car (far more than I could get out of it, I know) and intend to keep it until the engine dies; If we are still using gas in 15-20 years, I may even have the engine rebuilt again (but probably ported).

I know I'm not going to squeeze every last HP out of this engine- I didn't have it ported at all during the rebuild, (I was naive) and do not intend to port any time soon.

Can someone, if you have time, explain what an S-AFC is? How much HP and MPG do I stand to gain with one? how much should one cost me? I've seen the term thrown around, but really don't know much about modifications to the car; I've been more concerned with restoration. Now that I've finished restoring it, I want to get a little bit more power out of it before I start putting money away.

*edit* I know we're getting off the original subject a bit, but I think there's some good information here :D

phoenix7 08-29-07 05:32 PM

the S-AFC (super-Air Flow Controller) is an APEX-i unit used to control your injectors. When used with a wideband oxygen sensor you are able to take the Air-to-Fuel Ratio (A/F or AFRs) that the wideband reads and you (OR THE TUNER) adjust the injector's flow to add or remove fuel by a percentage at a certain RPM and/or throttle signal.

I'm sure you know that more air = more power but if you lean out your fuel mixture too much you can detonate and kill your motor. For regular gasoline the perfect AFR is 14.7:1, this is stoichiometry. The closer you get to 14.7 the more power you can make but the more likely you are to detonate. Some people tune their cars in the low to mid 11's while others go as lean as mid 12's. From the little reading I've done you CAN lean out the NA's a tad more than a TII but that's not something I feel 100% comfortable saying.

The amount of HP you can make differs from car to car. compression, modifications, the ability and confidence of the tuner. My car was dynotuned to 150WHP while others with the same or less mods have made closer to 170Whp. Mileage also differs. I get anywhere from 18mpg to 25mpg. I think I can improve on these things once I get the wideband installed.

I would not look into a gen 1 AFC because that is way too old now. I currently have the S-AFC and it works fine for me and these run anywhere from $100-$150. There is another model, the S-AFC II, which has extra features but in the end it does the same thing but at a slightly higher cost($150-$200). The newest generation of Fuel controllers from Apex-i is the AFC-NEO that costs around $300 (on sale here: http://www.extremepsi.com/store/cust...cat=946&page=1.)

The thing that caught my eye about the NEO was their Vtech controller incorporated for the Honda cars. I was trying to see if it was possible to take that Vtech controller and use it for the 5th and 6th ports (which is essentially the same thing a Vtech, vvt-i, mivec, etc., etc.) so you can control when they open. This popped into my head as I post this so it's not thoroughly thought out yet. I have to read/research some more to know if it's even possible..

There ARE other companies that sell fuel controllers but they go by different monikers besides AFC or S-AFC.

phoenix7 08-29-07 05:40 PM

I can get into why the piggybacks are considered bandaids, IMO, but it doesn't apply to NAs as much as it does to TIIs. This is mainly because the NAs rarely make enough power to justify changing the injectors as opposed to a TII.

BTW re-read my post above because I went back and edited several things since I posted it.

PvillKnight7 08-29-07 06:08 PM

you should be able to buy a wb02 and a safc for together for less than $500. I know its kinda pricey but they are good investments and can be used on any car you want to tune.

MmSadda 08-30-07 11:24 AM

Phoenix7 and PvillKnight7-
Thanks for your input, guys!
Phoenix7, That was a lot of very useful information for someone who is as inexperienced with tuning as myself; You did a great job of explaining the benefits and risks associated with S-AFC tuning, as well as what it does.

MmSadda 08-30-07 11:25 AM

Phoenix7, I just re-read your post again; Are you saying you're running an AFC-II, without using a wideband? If I was to do what you're doing, would I be putting myself at significant risk of detonation?

CRYSTON 08-30-07 12:02 PM

you can tell if your running rich if you smell the car burning the gas

The Shaolin 08-30-07 01:03 PM

Get an SAFC used from here for like, $160.

Get the AEM WBo2 brand new from www.qksltwo.com for $265.

phoenix7 08-30-07 01:15 PM

I have the S-AFC, not the S-AFC II, and I'm not running a wideband yet. I did, however, get my car dynotuned. I chose to buy a wideband so I can do my own tuning instead of spending 300-500 each time at the dynotune.


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