Just like it says, does anyone know how to tune the vq30de using the safc II? Any input is appreciated, thanks

 

Dyno+Wideband. Adjust fuel until AF = 13.0/5

 

this may be a stupid question but what is wideband. I understand the AF 13.0/5 but would going to 11.5-12.0 hurt it?

 

this may be a stupid question but what is wideband?. I understand the AF 13.0/5 but would going to 11.5-12.0 hurt it?

 

sorry i didn't mean to double post

 

no replies?

 

Wideband o2 sensor gives you data which maps out a/f ratio, and then you tune accordingly.

Why would want you tune that rich? Yes it will hurt power if you go that rich.(this is as.suming you posted in this particular forum for the right reason)

Delete one of them.

 

The point of getting the SAFC-II is to lean out your a/f mixture so that your not as rich, thus picking up much power.

 

Not necessarily, because it all depends on your a/f.. mines lean as sin, needs more fuel, so as I said, depends on exsisting A/F.

This is relative to kevlo's post. Aim for that # when in this forum.

 

I suppose I shouldn't have spoke for everyone, I was just speaking from my experience as I am rich as hell. This 00VI will be on tomorrow though, finally got all the pieces and I didn't spend over $130.

 

11.5-12.0 is an AF ration you would shoot for if your had FI. An NA max would want to be around 13.5ish. Unlesss your AF is much leaner of richer than 13ish then an SAFC is not gonna do a whole lot for you. You would get the most power by getting an AFPR, turning up the base fuel pressure to run rich...say 11.5:1 to 12.0:1 then taking fuel away via the SAFC. That way you can add a bit of timing as well as get your wanted AFR

 

How did you do that?

 

vq30de/k's run FPr at 3.0bar
vq35de run fpr at 3.5bar

do you need to turn up the FPR on 290cc dek injectors in a vq30?

 

Friend of a friend that works at a Nissan salvage yard in California. Got the Manifold and TB for $120 shipped to my door.

 

Definitly not, my PLX M300 wideband reads 10-11 AFR with the DE-K injectors.

 

As per I30Mike's post, which I think he was quoting, thus wanting to get the mentioned results, yes you do if you want the added timing.

You will have to lean it out some using some type of AFC though, but it's all explained in another thread, and Mikes post is suffecient enough.

 

As I30Mike said, you would richen the A/F to around 11.5-12. With DE-K injectors, which he has should put him at around 10-11. So turning the FP up would richen it more then 10. At that point, I just think it would be too much correction with a S-AFC. He would be fine with picking up timing and gaining power right now with the DE-K injectors and leaning it out to 13.5.

 

What do DE-K injectors have to do with this? 4th gen use side feed and 5th gen use top feed....

 

 

the 00VI people that have used both lower/upper intake manifolds would like to know once you put the DE-K injectors on from 259cc to 290cc would you need to raise fuel pressure to accommodate for 30cc difference O_O

 

.....

 

I would like to also know this as well.
I'm putting on a FULL 00vi kit and I think i'm gonna end up getting a VAFC to activate the VIAS as well as use it to tune the car out....


Mike

 

No you don't need to raise the fuel pressure. What happens is at WOT the injectors actually dump more fuel in than the 4th gen injectors. Which makes your af ratio richer than what it should be. My af ratio dipped all the way down into the 10's (untuned) right after the swap and I adjusted to almost 13 but mainly it still in the 12's. Thats why I need to go back to the dyno and get it to about 13.5 all the way across.

 

So Mike if your Air Fuel Ratio when dynoed was 11.9 the Apexi SAFC-II isn't for you - you recommend getting an AFPR, which is what? (Sorry to be ignorant, I can source an SAFC-II but have never heard of an AFPR)...damn acronyms.

Wouldn't an SAFC-II give you better throttle response and give the broadest possible power/torque band given your modifications?

I hope you say no because it will cost me $1,200NZD (around $850USD) to buy/install/tune the SAFC-II in my SMX.

Cheers Mike.

 

The further away from 13.5 your A/F, the more you need the SAFC.

FPR = Fuel Pressure Regulator. More info here re: Mikes post. http://www.forums.maxima.org/showthread.php?t=434821


Throttle response wont be affected by the SAFC, unless you tune part throttle frm 1000 RPM or wherever idle is, and even then it's a shot in the dark..

The gains from a SAFC all depend on how far your A/F is from 13.5 ....typically.

 

That's odd...when I dynoed with the DE-K, my AF ratio was mostly between 13-14. Even though the JWT ECU isn't programmed for the 290cc injectors, maybe it has the ability to compensate, or maybe it's just that conservative However, the dyno operator advised against not spraying nitrous when running at this AF ratio, but I assume he didn't fully understand the JWT system, and I didn't feel like explaing at the time.

 

The difference is you have the whole DE-K engine (which might make a difference) and a JWT ECU that had an AF ratio mapped out and once you put your stock ecu back in you AF ratio's were in the 11-12. All I know is after the swap untune my AF ratio was in the low 11's. Each car is different so everybody needs to get on the dyno and tune for their needs.

 

Thanks for that Nmex. Either way the tuners are too busy leading up to Christmas to do my car so I'll have to wait until late January at least to do it for real.

 

Your post confuses me....not sure you understand


An SAFC won't give you better throttle response. In general it is not a good tool to use for anything but small WOT ARF corrections. An SAFC does not do much at all, it is an old school way of tuning and really is not used much anymore. There are much better tuning devices available these days than an SAFC.

You would be crazy to pay $850 to get an SAFC, have it installed and tuned. You can get used ones for $150-$200, and install takes only a couple hours and can be done by anyone with basic knowledge. The gains, if any at all, buy installing just an SAFC on to a bolt on maxma with not be worth $850. Trust me.

My post had to do with taking advantage of an SAFC's disadvantages. The disadvantage being that making corrections with an SAFC indirectly will change timing. Generally not a good thing because you don't want to mess with timing unless you know exactly how much your advancing or retarding it. But it can be usefull if you know what your doing. When you take fuel away with an SAFC you indirectly advance timing. Small corrections wont' do much, but when you get to -20% fuel or more timing will be noticeably effected.

For a basic bolt on NA maxima to take advantage of this one would need to richen up their AFR so that they could take fuel away with the SAFC. An easy way to do this is to use an Adjustable Fuel Pressure Regulator. Bring the AFR's down to 11.5:1 or 12.0:1, this way you can make the large corrections needed with an SAFC to bring the AFR's back up to the 13's and thus add in some timing at the same time. You have to bring the AFR's down to do this, you can go taking away 20% fuel with an SAFC if your starting at a 13.5: AFR.

The whole idea behind this is that it is a cheap way to go about adding in some timing. But that is negated if your going to have to pay an arm and a leg for install and tuning of the SAFC.

 

im assuming that by better devices you dont mean the SAFC-II...what can be used insead?

 

SMT-6/Greddy Emanage...

 

Is the VAFC considerably better than the SAFC? Or should they both be tossed for something like SMT-6/Greddy Emanage?

 

IMO vafc2 > safc2 but still limited compared to smt-6/emanage. the v has double the amount of tuning points and the ability to control the vias switchover for whoever has the 5th gen 3.0 manifold. not sure if others use it on the mevi. only cost me 10 bucks more for the vafc2 on ebay.

 

When I say SAFC, I mean SAFC-II. An SAFC is very basic, Can only adjust AF in 200 rpm incriments, can't really "tune" anything but WOT throttle, no timing control, doesn't really control larger injectors, doesn't data log, etc...


there are alot of choice in devices to tune a car besides an SAFC. Emanage, ROM tuning, SMT, stand alones, etc