Best Bang For Your Bucks

[paulr33]

it might actually focus some time n effort on the 6000 dropoff

i could feel the power drop on the dragstrip at heathcote

changing past 6 grand felt slower at the strip.

[Cubes]

it might actually focus some time n effort on the 6000 dropoff

i could feel the power drop on the dragstrip at heathcote

changing past 6 grand felt slower at the strip.

annd... what did you manage to run?

as per the 0-100 times thread the first 60ft is pretty damn important.

[paulr33]

i posted it up before, 13.7 @ 105.mph was my best

with a busted lsd and cold track

raction 0.6933

60ft 2.13

et 13.75

mph 105.5

ambient temp 16.1

humidity 60%

[Quinny]

it might actually focus some time n effort on the 6000 dropoff

i could feel the power drop on the dragstrip at heathcote

changing past 6 grand felt slower at the strip.

I am surprised that is has taken so long. That would piss me off if I realised a flat spot like that.

[dezz]

my bog stock s2 R33 made 182rwkw, so I beat you all

[justin911]

ive got a question relating to all this.....

when i used to have my safc2 i made 195kw or so at 10psi...

and with my powerfc i make like 195kw on 12psi.....

Now i no the airflow setting in the pfc is pretty much the same as the safc2s main function... so ive never understood why it makes more... ?

and also with the pfc if you up the timing it adds power etc... but how come i made the same power with the less boost and i didnt have to changing the timing with the safc2 ????

also before anyone ses 'crap tune' the pfc was tuned by the same mechanic who tuned the safc2 originaly.. same dyno etc etc...

and also previous differant mechanics tuning my pfc got the same result.. around 195kw

so yeah how does that work ?? cause ive seen other ppl with safc2's and they also seem to make in the 190kw mark with only 10psi.... ???

[Quinny]

my bog stock s2 R33 made 182rwkw, so I beat you all

182rwkw is not stock.

C'mon, out with it...

[dezz]

stock as a rock. didnt even have an exhaust at the time

[Quinny]

stock as a rock. didnt even have an exhaust at the time

Really? Sounds like a happy dyno, considering that a stock R33 puts out 187kw at the engine...

[Tangles]

quinny - what mods have you decided on?

over or under budget?

[Sydneykid]

ive got a question relating to all this.....

when i used to have my safc2 i made 195kw or so at 10psi...

and with my powerfc i make like 195kw on 12psi.....

Now i no the airflow setting in the pfc is pretty much the same as the safc2s main function... so ive never understood why it makes more... ?

and also with the pfc if you up the timing it adds power etc... but how come i made the same power with the less boost and i didnt have to changing the timing with the safc2 ????

also before anyone ses 'crap tune' the pfc was tuned by the same mechanic who tuned the safc2 originaly.. same dyno etc etc...

and also previous differant mechanics tuning my pfc got the same result.. around 195kw

so yeah how does that work ?? cause ive seen other ppl with safc2's and they also seem to make in the 190kw mark with only 10psi.... ???

When you lean out the A/F ratios with the SAFC it also advances the ignition timing at the same time. Remember all the SAFC does is to change the voltage from the AFM that the ECU sees. Usually that means reducing the voltage to lean out the A/F ratios and overcome the Rich part of the Rich and Retard ECU mapping. By reducing the voltage the ECU thinks the engine is operating at a lower load and hence stops (or at least reduces) the Retard part of the Rich and Retard mapping.

This means that you have to compromise the tune, sometimes you want to go a little bit leaner but you can’t because you get pre-ignition from the advanced ignition timing. Up to a certain power level (usually 185 – 200 rwkw on an RB25DET) this is not too much of a compromise. But once you go over that power level, the compromise starts to get greater, exponentially.

That’s the advantage of the Power FC you can control the fuel and ignition independently, no compromise required. This really comes into it own once you get past that power level. As yet I havn’t been able to find the upper limit of a Power FC, certainly 1100 bhp is not it.

The power output of an engine can be considered to be like a chain, only as good as its weakest link. For example if you have an exhaust that will only flow 195 rwkw of air, then tuning the engine slightly better won’t make anywhere near as much difference as if it had a 300 rwkw capable exhaust.

In relation to the 10 psi versus the 12 psi, the standard turbo really gets pretty inefficient at 12 psi and starts to heat up the airflow. If the intercooler isn’t up to it (removing that excess heat) then the extra boost won’t actually manifest itself in extra power. This is particularly noticeable on the dyno when you have only a fan, not 180kph air flow as you would have on the road.

cheers

Edited June 16, 2006 by Sydneykid

[mad082]

his dyno runs were also done at different times of the year. pfc in summer, safc in winter, so there would be a bit of a difference there as well, even if it is only a few kw.

[justin911]

thanks SK that clears that up

[justin911]

yeah had the safc in winter.. but also had the pfc done in summer and in winter... have had the pfc retuned a couple of times now for various reasons hehe

his dyno runs were also done at different times of the year. pfc in summer, safc in winter, so there would be a bit of a difference there as well, even if it is only a few kw.

[paulr33]

i can make any dyno figure you like at the end of the day as well

stick the air inlet temp up the exhaust and then remove the shootout mode parameters. or even just dial in more manual correction, change the ramp rate and so on. the dyno is useful as a tuning tool and good for back to back comparision when used on the same dyno with the same settings. this is the point of shootout mode, to lock those settings and compensate for airtemp changes.

if you have a run and it says RR015 and then a run of RR013 the results will be different, same with AT and IT.

Ramp rate

intake temp

ambient temp

[justin911]

not sure if your implying my safc2 figures were doctered up abit by the tuner by like i said i did get the 13.4 with the safc2.. which is pretty much onpar with what youd get with a pfc..

anyways not stating one is better than the other... was merely asking a question

[Quinny]

quinny - what mods have you decided on?

over or under budget?

Most likely over budget - but I should be used to that by now.

Power FC

ARC Turn-Flow FMIC

EBC

I am undecided yet if I should get a hi-flow. I could get a GCG one, but that would blow the budget completely, or I could get a Slide Performance one, but I am not sure about using a bush bearing turbo.

I will either:

1: get the above mods and a GCG hi-flow. Get as much power as i can with the standard fuel system then retune it later when I get a new pump & injectors

2: Get the above mods, maybe a Slide Performance hi-flow and spend the rest on giving the car a tune up (new coilpacks etc).

I need to sell my Commodore first (hopefully soon), once I have the money I will make up my mind.

[paulr33]

i guess at the end of the day

if you turn the car off unexpectedly or you have to

then theres a big risk youll kill the bearings in the plain bearing turbo

[Quinny]

i guess at the end of the day

if you turn the car off unexpectedly or you have to

then theres a big risk youll kill the bearings in the plain bearing turbo

That is what I am thinking, I have been burnt using cheaper parts before, hence the reason I am going for good parts rather than cheaper parts.

Ultimately, my car needs to start first time, every time. I can't afford to have the car off the road for any reason, so if I have to spend a little more money to ensure that, then so be it.