BklynRX7

Hey i was just wondering if it would be worth it to get a used safc and lean out the N/A a bit since everyone goes on about how they run rich stock. Ive searched and see everyone suggesting it but noone whos done that alone and shown a proven dynoed gain. Does anyone have any hard info or atleast and intelligent guess on about how much power could be freed up by simply leaning it out a bit?

koukifc3s

iTrader: (3)

https://www.rx7club.com/2nd-generation-specific-1986-1992-17/gtus-dyno-day-159hp-121tq-261173/

RarestRX got 15hp from it.
I've yet to tune mine.

Sideways7

iTrader: (7)

Plus you'll get better gas milage.

Icemark

The drawback is questionable engine lifespan.

See at upper RPMs primarly the unburnt fuel and only a minor amount of injected oil, become the lubricants for the apex seals, so while leaning does make for more power and better combustion, it also runs the drawback of possibly more engine wear.

Now I don't have long term proof of this, nor can I say without any doubt that running leaner will result in increased major seal wear, I am only saying from short term (20K miles) test experience taht I have been playing with, that there is some increased wear (chatter marks and minor opened seal grooves) when comparing two motors with simular miles and one with a leaner burning, one with stock ECU settings.

koukifc3s

iTrader: (3)

so what AFR would you recommend?

BklynRX7

So if i lean it out to just richer than stoic I could theoretically reduce this wear right?

Also is it possible to tune a safc to this effct without a wideband? even close?

skatingsamurai

i pretty much speak for everyone when i say, not really... you can technically tune by feel as there people who do it but if you dont have experience with tunning, dont know the general "feel" of your car, have an exaust gas temp gauge, or wideband, i wouldnt true to "tune"

skatingsamurai

although im not a hardcore tunner, from what i have been told you shouldnt generaly go past 13.0 AFR at WOT

staticguitar313

iTrader: (2)

''The drawback is questionable engine lifespan.

See at upper RPMs primarly the unburnt fuel and only a minor amount of injected oil, become the lubricants for the apex seals, so while leaning does make for more power and better combustion, it also runs the drawback of possibly more engine wear.

Now I don't have long term proof of this, nor can I say without any doubt that running leaner will result in increased major seal wear, I am only saying from short term (20K miles) test experience taht I have been playing with, that there is some increased wear (chatter marks and minor opened seal grooves) when comparing two motors with simular miles and one with a leaner burning, one with stock ECU settings."

what about on premixed engines??

jacobcartmill

iTrader: (6)

premix saves lives.

staticguitar313

iTrader: (2)

yeah i have my safety net in place, i'm still running that OMP though, its going to go soon im sure.

Kahren

iTrader: (13)

s5, full rb exhaust, pineapple 6 port sleeves :/ and a cone filter
timign was left stock, only fuel was adjusted with the help of the afc
enjoy

Icemark

That I couldn't say, but any additional top end lubrication should help.

The motor that I ripped apart after rebuilding with the AFC and 20K was just run with the stock MOP system, and conventional fuel

Jager

iTrader: (10)

Thats awesome Kahren. I wonder what a Megasquirt would do with a stock car + bolt ons.

jpd3253

Could the engine conditions after 20K be attributed to driving habits, such as taking it beyond redline? Also, how was the engine used, daily driver, track, etc?