Fine Tuning JWT ECU - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

S14mc · 08-24-2007, 02:33 PM

I have a JWT set up for Z32 maf and 550s on my SR. I understand that Jim Wolf writes conservative programs. When I went on a dyno the other day I saw that my AFRs were running rich, I wanna say 12s-13s (Im at work and I forgot my dyno sheet). Can I use a safc to lean it out a bit or should I go wideband? I know I can cut some fuel but would I have to mess with the timing, since i'm leaning it out a bit?

Any help would be great.

Thanks.

bigOdom1 · 08-24-2007, 02:41 PM

safc to take out fuel but need a wideband when tuning always.

go get back on the dyno and take a little away where its rich after you set the points on the safc to coincide with different rpm ranges. when the a/f is where you want it then give some timing at 1 degree increments and see if it helps/continue tuning with safc if needed

GRIPPY · 08-24-2007, 03:48 PM

Man 12-13's is TOO LEAN if you mean that is under load. If you mean it is 12-13 afr at idle, then yes that is a little rich. An SAFC should be able to make those corrections, but yes you need a wideband to see what changes you are making. I wouldnt touch the timing, im thinking the JWT timing map is pretty solid.

Iceman00 · 08-24-2007, 03:52 PM

If CodyAce was here, he'd tell you a SAFC is a $300 way to hack up your wiring harness.

In truth though, from what I read so far, JWT ECU's Don't play well with the SAFC...

orion::S14 · 08-25-2007, 07:26 AM

Leave it be...messing with fuel will net you very little power for the $$$ spent.

The real key is the timing...which is conservative on a JWT ECU. But you're stuck with what you got, unless you wanna make a global change by rotating the CAS / distributor (SR or KA-T?).

- Brian

codyace · 08-25-2007, 08:33 AM

How can you tell that your car is running those AFRs? Any proof? What about the dyno output?

Also, don't blame the ECU tune right off the bat. Are you sure don't have any vacuum leaks? What is your base fuel pressure? Is your car timed correctly? There are a ton of small things that could potentially make you run richer than should be.

As far as being conservative, they most certainly are...but in the same aspect have you ever heard of a JWT car blowing up (well those who run sill setups don't count either...) Now compare that to other setups....

- In that same aspect, having a car that makes 350 whp, yet reliable, is much more fun than a 365 hp one on the edge

- Also, by the time you have a JWT ECU, get an SAFC, and tune it...you're looking at over 1000 dollars invested....with an extra 400 being involved with a new SAFC, and tune to gain few hp. If you're got hat money, why not get a standalone and have that tuned?

Quote:

Originally Posted by Iceman00

If CodyAce was here, he'd tell you a SAFC is a $300 way to hack up your wiring harness.

In truth though, from what I read so far, JWT ECU's Don't play well with the SAFC...

LOL. F-in A right man.

I'll maintain that unless you have a DSM car, or some oddball 250 hp or lower car that you turboed for fun, that an SAFC is about as useful as a narrowband AFR gauge. Throw them in the brush, all day everyday.

Quote:

Originally Posted by orion::S14

Leave it be...messing with fuel will net you very little power for the $$$ spent.

The real key is the timing...which is conservative on a JWT ECU. But you're stuck with what you got, unless you wanna make a global change by rotating the CAS / distributor (SR or KA-T?).

- Brian

Timing is a HUGE improvement for cars if they aren't on. A good friend of mine used to go around local Nissan meets and help set everyones timing with his N Probe, Timinglight, and tools. SOOOOOO many cars were off from kids playing with them and having no clue hehe.

S14mc · 08-28-2007, 02:28 PM

Yea, I think I'll go with like an PFC or AEM standalone. Anyone know who wants a JWT ECU set up for 550s and Z32 maf?

johngriff · 08-28-2007, 02:38 PM

Dont get the PFC and the AEM is too much money.

Haltech Plug and Play

I will even make you a free custom base map.

But whatever you do, DONT get the AFC.

Here is a write up I did a year ago.

http://www.zilvia.net/f/showthread.p...78#post1077578

John

steve shadows · 08-28-2007, 02:47 PM

Quote:

Originally Posted by johngriff

I will even make you a free custom base map.

derived from what?

08-24-2007, 02:33 PM	#1
S14mc Leaky Injector Join Date: Dec 2002 Posts: 136 Trader Rating: (0) Feedback Score: 0 reviews	Fine Tuning JWT ECU I have a JWT set up for Z32 maf and 550s on my SR. I understand that Jim Wolf writes conservative programs. When I went on a dyno the other day I saw that my AFRs were running rich, I wanna say 12s-13s (Im at work and I forgot my dyno sheet). Can I use a safc to lean it out a bit or should I go wideband? I know I can cut some fuel but would I have to mess with the timing, since i'm leaning it out a bit? Any help would be great. Thanks.

08-24-2007, 02:41 PM	#2
bigOdom1 Nissanaholic! Join Date: Nov 2005 Location: Auburn/Birmingham AL Age: 41 Posts: 1,817 Trader Rating: (4) Rides Gallery: bigOdom1 Feedback Score: 4 reviews	safc to take out fuel but need a wideband when tuning always. go get back on the dyno and take a little away where its rich after you set the points on the safc to coincide with different rpm ranges. when the a/f is where you want it then give some timing at 1 degree increments and see if it helps/continue tuning with safc if needed __________________ my car domain that good review thread

08-24-2007, 03:52 PM	#4
Iceman00 Zilvia Member Join Date: Oct 2006 Location: Around Posts: 170 Trader Rating: (0) Feedback Score: 0 reviews	If CodyAce was here, he'd tell you a SAFC is a $300 way to hack up your wiring harness. In truth though, from what I read so far, JWT ECU's Don't play well with the SAFC... __________________ * > Drifting JWT powered Altima

08-25-2007, 07:26 AM	#5
orion::S14 Nissanaholic! Join Date: May 2003 Location: Orange Park, FL Posts: 1,666 Trader Rating: (0) Feedback Score: 0 reviews	Leave it be...messing with fuel will net you very little power for the $$$ spent. The real key is the timing...which is conservative on a JWT ECU. But you're stuck with what you got, unless you wanna make a global change by rotating the CAS / distributor (SR or KA-T?). - Brian __________________ www.KA24DEvelopment.com

08-28-2007, 02:38 PM	#8
johngriff Post Whore! Join Date: Jun 2004 Location: Long Beach, CA Posts: 4,103 Trader Rating: (4) Rides Gallery: johngriff Feedback Score: 4 reviews	Dont get the PFC and the AEM is too much money. Haltech Plug and Play I will even make you a free custom base map. But whatever you do, DONT get the AFC. Here is a write up I did a year ago. http://www.zilvia.net/f/showthread.p...78#post1077578 John __________________ [email protected]

08-24-2007, 03:48 PM	#3
GRIPPY Join Date: Oct 2006 Location: Edmonton, Alberta Age: 39 Posts: 16 Trader Rating: (0) Feedback Score: 0 reviews	Man 12-13's is TOO LEAN if you mean that is under load. If you mean it is 12-13 afr at idle, then yes that is a little rich. An SAFC should be able to make those corrections, but yes you need a wideband to see what changes you are making. I wouldnt touch the timing, im thinking the JWT timing map is pretty solid.

08-28-2007, 02:28 PM	#7
S14mc Leaky Injector Join Date: Dec 2002 Posts: 136 Trader Rating: (0) Feedback Score: 0 reviews	Yea, I think I'll go with like an PFC or AEM standalone. Anyone know who wants a JWT ECU set up for 550s and Z32 maf?