AFR's for jwt tunes

[spooled240]

I have a jwt tune, 555cc inj. blow-through z32 mafs and my car runs pretty rich. You can just smell the rich fumes every time I back into my driveway and my car puffs a little smoke from time to time when I blip the throttle. I don't have a wideband, but I know that I should get one in the near future but I'm still wondering if there is a flaw in my setup that is making my car run rich instead of just the tune. The car still runs ok and drives ok but it guzzles gas and making my oil black . The guy I called at jwt said that the afr at full boost is around 11:1 to 11.5:1 and I heard jwt tunes are generally more rich. For those of you guys that have jwt tune, what is your afr's at idle and full boost? thanks, this is a problem that's just been growing on me when gas is $3.57/gal for premium

[S13FX]

Get a Wideband, get a SAFC, and fine tune.

it's not really going to help you us telling you our afrs if you don't know what yours are. But the 11.1 to 11.5 in boost seems right.

Also is your bov recirculated or open?

[WDRacing]

^^^

What he said...every car is different. Do you have a adjustable FPR? You definitly need a wideband.

[spooled240]

well i wanted to know if you guys with the jwt ecu's are experiencing the same rich condition I am..I have an open at. bov/don't have an adj. fpr. My car just passed smog with the stock ecu and the nox and hc's were ok, so it's definitley the tune and/or my setup

yeah about the wideband and the safc: that's quite a bit of money and work (welding another exhaust bung, installing safc) so I'm gonna try to work out any possible bugs..These ecu's are plug and play, you shouldn't have to fine tune it IMO: especially when the reflash costs 600

[S13FX]

Like WD said. Every car is different.

You can have two engines rebuild exactly the same with the exact turbo parts, use the same JWT ecu on it, and I guarantee you will see differences in AFR's.

and nm about the BoV question I didn't notice you have a blow through.

Anyways, I ran a rom tune on my car which I tuned my self, and I still had corrections with my safc.

Plus JWT never drove your car, never seen your car, of course their going to tune a lil on the rich side to keep you safe.

I don't mean to be an ******* or anything, but I mean if your not willing to to do a lil work for a wide band and safc I shouldn't hear any complaining about how rich your tune is hehe.

I understand fully that time and money is something not a lot of us have believe me, Im work full time and Im a full time student.

[WDRacing]

well i wanted to know if you guys with the jwt ecu's are experiencing the same rich condition I am..I have an open at. bov/don't have an adj. fpr. My car just passed smog with the stock ecu and the nox and hc's were ok, so it's definitley the tune and/or my setup

yeah about the wideband and the safc: that's quite a bit of money and work (welding another exhaust bung, installing safc) so I'm gonna try to work out any possible bugs..These ecu's are plug and play, you shouldn't have to fine tune it IMO: especially when the reflash costs 600

I'm not saying you need to buy a safc and fine tune anything. It's just that without a wideband how are you supposed to know exactly how rich you're running. Maybe it's only rich on boost, maybe just at idle. If it's rich the whole time then a simple reduction in fuel pressure will fix that. Maybe the O2 sensor is bad, or getting bad. Point being, unless you know for sure, it's hard to actually diagnose if there's a problem. If it's to rich, you may rinse the oil off of the cylinder walls and scratch them, and get fuel in the oil.

JWT is historicly been tuned on the rich side of things. However, it should only be rich on boost.

WD

[spooled240]

I don't mean to be an ******* or anything, but I mean if your not willing to to do a lil work for a wide band and safc I shouldn't hear any complaining about how rich your tune is hehe.

don't worry s13fx, i know exactly what you mean. It's not the work, just the money wideband and a safc gonna be over 400 maybe i should just go to the local dyno and get the afr's there..wanted to get my hp numbers anyway

[WDRacing]

Bummer you can't just borrow one...a new O2 bung and plug is like $6.

WD

[DammitBobby]

I am running JWT ECU 740cc`s and the timing and AFR`s are aggressive. You need to atleast buy a fuel pressure gauge and make sure your fuel pressure is correct. Walbro fuel pumps have been known to raise fuel pressure above stock. JWT ECU is programmed to stock fuel pressure so anything above stock will cause it to run rich. By the way a gauge and fitting can be had around 25 bucks.Good luck!

[spooled240]

thanks for the help so far guys

do you mean "aggressive" like really lean? My fuel pump is stock. I pretty sure my car is a little too rich at idle, so I bet I can get away with just lowering the fuel pressure but there's no way in hell i'm gonna lean it out without a wideband..

I definitley can't afford a brand new wide band kit as of right now (got raped by college fees lol) but it'll do for now maybe i'll just weld another o2 bung and plug it for now when I get the chance to borrow/buy a wideband. Then maybe a safc if things don't work out..

First things first tho, need to find out my afr's whether it be via wideband or dyno shop..

[DammitBobby]

I blew 1 old tired engine and 1 stock rebuilt engine before I realized the timing ramped up to 19 degrees at WOT. AFR`s are around 12 at WOT. The only way you are going to know what is going on is to have your laptop connected to the ECU.

[Florida240sx]

I got an mdm techtom to monitor mine. But I have enthalpy ecu $500 and retunes are only $125 and take 3days.

[spooled240]

ok i checked the oil, it's dirty (so I have to change that soon) but doesn't look deluted or doesn't smell like gas-just smells like burnt oil, i'm guessing from the turbo..I've seen some pretty bad gassy oil and this oil is not too bad.

The smoke my car was puffing during accel. after idling at rest is white/blue (not black from a rich condition like I thought) probably from the turbo as well..so i don't think the tune is running crazy rich to the point where it's damaging my engine, just a little hard on the mileage

[spooled240]

My plugs were crispy brown so i think i'm good

This is a e-mail I got from Ben at Jim Wolf in case anyone else was wondering..

What are the default air fuel ratios (at idle and wide open throttle/full boost) you guys setup up the ka24de turbo ecu's with? thanks

When we upgrade an ECU for a turbo application, we set-up the program to run about 11.25:1 to 11.50:1 air fuel ratio at boost on wide open throttle. The idle and light throttle air fuel ratio is controlled by the oxygen sensor when the engine is warmed up and this is going to try to maintain about 14.7:1 air fuel ratio which is "[stoichiometric]". If you are on accel but not heavy boost and more throttle enough to get you out of closed loop operation then the air fuel ratios will be between around 12:1 to 13:1 range. Air fuel ratios leaner than 16:1 and richer than 10.5:1 will cause possible driveability issues depending on the air flow and throttle position.