SAFCII vs Power FC

[gtstii]

If planning on having an r33 gtst with the following:

- full exhaust (dump/front/rear)

- pod & CAI

- stock intercooler

- EBC (11psi)

what is the better way to go (considering I dont want to blow mega bucks) a Power FC or an SAFC?

I know overall a power FC is a better unit, but wanted to hear opinions from people who know or those who have gone from an SAFC and upgraded to a Power FC (with similar mods)?

Is it worth the extra $$ to go for a Power FC considering the std turbo & cooler?

The main thing in terms of making power I guess is the ability to tune ignition with the PFC, will the ignition map really be that bad with the above mods?

How much extra over the SAFC will the PFC give in terms of kW?

thanks

[dabigbolf]

definatley go for a saf-c if thats all you want to do to your car. But in terms of bang for bucks.... I'd say spend the money on a front mount intercooler, to replace that side mount heater box. You have to spend an extra $300 to $400 over a saf-c but you will not regret it.

And then later down the track you when saf-c's are becoming cheaper you could snatch that up for $300....

Only reason i say go a front mount, is because if you are considering a power fc, i take it you are willing to spend money, and a front mount intercooler is your next best investment, as far as power wise.

can get some good quality second hand ones at a decent price. Gtr ones, or something a bit smaller if you must...

best of luck,

[4 Doorz]

mate, go apexi pfc.....full replacement the standard comp doesn't compensate ignition map for AF map...leading to more detonation

[Silver-Arrowz]

GTST's have a restrictive intercooler if I'm not correct??? Maybe that's the better option first. As for PFC or SAFC depends on how much your going to do to it later. Even still, get a SAFC then a PFC later as there are always people wanting a SAFC anyway.

[sewid]

Well yeah. I would go a larger intercooler first before the ECU. Then PowerFC.

Don't buy the SAFC because you will eventually want to upgrade to the PowerFC anyway (even if you don't know it yet). Since the price difference is only $300 anyway its not a huge leap.

Oh yeah, and buy it from Japan. www.greeline.jp or www.nengun.siteblast.com. All aussie retailers having amusing prices for this stuff.

[JimX]

Sewid, the price difference is a lot more than $300. Looking at the Greenline site you quoted:

SAFC-II: 32918 yen = ~$422

PowerFC: 79233 yen = ~$1015

That's closer to a $600 price difference. On top of that, if you want the hand controller for the PowerFC, throw in another $360. (although admittedly you may need a fuel cut defender for the S-AFC). The S-AFC is also a lot cheaper to tune. For someone on a tight budget, I don't think you can go past a second hand S-AFC.

There is a big market for second hand S-AFC's, so even if you buy one and want to upgrade to PowerFC later, you will make most of your money back on the S-AFC. Especially if you bought second hand to start with.

I've thought about selling my S-AFC and getting a PowerFC, but the upgrade will cost me around $700 (or more) plus tuning costs. I'm already getting over 200rwkw with no pinging, so I can't justify this massive expense. Once I upgrade my injectors and can break through the 220rwkw barrier, I will look again at upgrading to a PFC. My choice was a lot easier because my car already came with a fuel cut defender and EBC.

[EnricoPalazzo]

the SAFC has a fuel cut defender doesnt it?

[JimX]

Not sure. Version 2 might, but I don't think mine does. I just left the one that came with the car in place, and my mechanic hasn't touched it. It might be wasting space

[sewid]

Originally posted by JimX

Sewid, the price difference is a lot more than $300. Looking at the Greenline site you quoted:

SAFC-II: 32918 yen = ~$422

PowerFC: 79233 yen = ~$1015

There is a big market for second hand S-AFC's, so even if you buy one and want to upgrade to PowerFC later, you will make most of your money back on the S-AFC. Especially if you bought second hand to start with.

Right, yeah shouldve looked at that. I was going off the price I had seen someone selling one for locally. Shoulda figured the Jap price would've been a lot better.

As you say, yeah there seems to be a good second hand market for them, although i cant see why. I have seen a lot of people selling them second hand (on these forums for example). A 2nd hand unit rarely goes for less than you can get a new one in from japan for. Silly but true. (Did a search for SAFCII in the For Sale forum, these are the prices i found from the top 5 hits: $500, $565, $350 (bargain), $650, $570). Is the moral of that story, buy SAFCII == Profit!? Or maybe, "do no research == get ripped off".

[rev210]

Originally posted by sewid

Well yeah. I would go a larger intercooler first before the ECU. Then PowerFC.

Don't buy the SAFC because you will eventually want to upgrade to the PowerFC anyway (even if you don't know it yet). Since the price difference is only $300 anyway its not a huge leap.

Oh yeah, and buy it from Japan. www.greeline.jp or www.nengun.siteblast.com. All aussie retailers having amusing prices for this stuff.

I can reccomend against the upgrade of the standard intercooler on a standard turbo setup. It's value for money sucks.

99% of the gtsts with upgraded intercoolers and standard turbos eat my dust, even with my little 205 tyres and 10psi of boost.

If you want to go pretty quick on a budget of say $2k then read the 13.4 second thread, page one.

I've spent about $2.5k so far without the NOS (add $500) and that package is good enough for a 12 on reasonable tyres (unlike the ones I presently have).

[Guest generic r33]

what is an safc?? (computer?)

[JimX]

S-AFC is short for Super Air Flow Converter (made by Apexi). In simpler words, it's just a mixture controller. Very popular on R33's because these cars don't have a reprogrammable ECU. It doesn't change the timing, but generally does quite a good job on mildly modded Skylines.

[rs73]

SAFC 1 dun have fuel cut defender. Not sure about SAFC 2.

However either someone said or wrote in some article somewhere that there was no fuel cut for over boost in R33, so buying a fuel cut defender for hi boost application for your R33 is a waste of money? Maybe the ECU just retard the timing when it senses higher boost to a point that it almost felt like a fuel cut?

[gtstii]

so, with the mods listed above - what differences would you expect to see in rwkw with:

- adding an SAFC

- adding a pfc?

what I want to know is if the ignition map is really that bad when you are only running about 11psi (0.75bar) or is it mainly the A/F ratio which goes haywire?

If with those mods and 11psi, there isn't that much power to be gained ($800 dollars or so worth) with a PFC, then I will go the SAFC!

[JimX]

Most of the power gains are made by the mixture map. Timing allows for a smoother power curve and slightly better economy and power. The PowerFC also compensates for temperature so you don't have to run "safe" (richer than optimal) mixtures to cater for summer heat. It also has a few other bells and whistles like a knock sensor readout.

If you have the bucks the PowerFC is worthwhile, but on my last S-AFC tune I got around an extra 30rwkw, at which point my injectors were maxed out. I couldn't get any MORE top-end power out of the engine with the current setup, although I could gain more in the lower rev ranges with a PowerFC where my injectors aren't at full duty cycle.

If/when I upgrade my injectors I will look at upgrading to a PowerFC.

[gtstii]

how do you mean you would get more out of the lower rev range with a pfc, by tuning the timing?

Is there much there to be gained is what i want to know?

[Guest Robo's]

Most of the gain is in the fuel, but dont discount timing. Timing with the PFC can be added/retarded throughout the rev range. There are gains to be had there. If you have the money, get PFC, if you dont have the money get SAFC.

Most people are getting 15rwkw with A/F mixtures adjusted and about an extra with timing changes. But there maybe some midrange etc.

[JimX]

As Robo's said, the timing (PowerFC) will help in the lower rev range. This is assuming you set your timing based on the upper rev range where you want your peak power. That will leave the lower rev range uncatered for, and the PowerFC will help.

In theory, both the PowerFC and S-AFC will give you almost the same peak power - for the latter you just set the timing to the optimal advance in the peak of your power curve. The PowerFC is still better all round, because you can run it slightly leaner with more safety.

With my car the AFR is around 11.5:1 at full noise - which is very rich, but doesn't bother me at all because I'm still maxing out the injectors anyway. I might be able to squeeze another 5kw out of it with a PowerFC by running it a little leaner, but I've already said above, this option would cost me over $700 (over $1000 including tune).

The real question you should be asking is how much money do you want to spend? If you've got lots to burn, get the PowerFC.