Jump to content
SAU Community

Recommended Posts

im running a 18 pound actuator and a brand new PFC boost control kit.

attached is a dyno print out showing the wave.

i have installed a 2mm restrictor in the feed line to the solenoid and the results are on the printout.

before i installed the restrictor it was even worse.

the boost settings are on 1.6 kgm cm

and the duty cycle is on 83 %

its a built rb25det with the new gt3540-iw

if i go any higher with the boost the wave gets bigger, and longer.

does any one have any other solution?

cheers Darren

post-24852-1163580810.jpg

Edited by dangerman4
Link to comment
https://www.sau.com.au/forums/topic/143365-r33-pfc-boost-controller-issues/
Share on other sites

how are the results varied when you adjust the duty cycle?

how is the solenoid connected? (draw a diagram)

where is the map sensor connected to (diagram would help)

the map sensor i joined with a T fitting into the line to the EBC from the plenum

and the wires plug directly into the pfc

the solenoid is wired up as you suggested in your pfc thread.

and checked with a multimeter.

if i go any higher with the duty cycle it becomes even more unstable.

the map sensor i joined with a T fitting into the line to the EBC from the plenum

and the wires plug directly into the pfc

the solenoid is wired up as you suggested in your pfc thread.

and checked with a multimeter.

if i go any higher with the duty cycle it becomes even more unstable.

What Paul suggested plus.......

Since you aren't using the EBC, reduce the amount of vaccum tubing, it's just buffering the signal to the PFC map sensor.

:O cheers :)

What Paul suggested plus.......

Since you aren't using the EBC, reduce the amount of vaccum tubing, it's just buffering the signal to the PFC map sensor.

:O cheers :)

Sorry Gary you have lost me.

i have a bad headache.

what ebc are you talking about?

where do you recomend running the lines from for the ebc?

should i get a fitting put into the outlet of the comp cover?

or what?

also should i plug the map sensor into the bov instead?

cheers

also to note the FC has a boost cut protect mode which may be activating, if the boost spikes 0.25kgcm2 over the value you dial in under SETTING, BOOST it will perform boost cut and back itself off. you may be hitting this, i would expect the engine check light to come on however

Looking at the boost curve it appears that the initially required duty cycle (at 3500 rpm) is not set correctly to meet your boost target of 1.6kg/cm).

1) At 3500 rpm your turbo is finally making enough pressure to overcome the actuator spring pressure. Prior to this your 2mm reducer and bleed off valve have no effect.

2) The sudden reduction in boost pressure after 3500 rpm is due to the solenoid bleeding off too much pressure. The duty cycle is too low at this point (even at 85% open) and the waste gate has opened too much due to too much pressure on the actuator. This suggests the reducer is incorrectly sized and you need to reduce the duty cycle (overall) in order to gain some control at the onset of boost - 3500rpm. My guess is that a bigger reducer would give you better control of boost at this point. The 2mm reducer cannot relieve enough pressure fast enough at this point and the waste gate is opening too much.

3) The boost response from say 4500 rpm to 6000rpm is fairly normal.

4) To retain a flatter boost curve after 6000rpm a multi channel boost controller might be needed to pull down the duty and open the waste gate as this turbo really starts to come on steam. A simple proportional controller as per the PFC may not be able to act fast enough in this sort of situation.

Holy f**k Sticks Batman!

Have a look at the boost of the Gizzmo!!

It's almost vertical!

What was that like to drive?

as its my wifes car she loves it, and my 2.5yr old daughter squeals out "More Boost Mum"

Being a auto it gets very interesting very quickly.

Steve might be able to shed some light as he made 320 something rwkw through a HKS3037 + all the nice bits to get there with 20 something psi with perfect boost control

You 'may' want to give Shaun a buzz as he tuned Steve's many years ago and knows them like the back of his hand.

Just like the AVCR they can be a hassle to setup.

Can anyone post the top attachment as I can't seem to view it. I also have the PFC boost kit and my boost curve is also like a wave and its affecting the whole power graph, im not sure if the self learning thing has changed it since the tune ill have to get it on a dyno again to check it out.

are you referring to 255 on the boost screen? its not used but apparently its part of the logic control. the manual doesnt say shit about it, datalogit cant touch it and the hand controller cant touch it

also to note the FC has a boost cut protect mode which may be activating, if the boost spikes 0.25kgcm2 over the value you dial in under SETTING, BOOST it will perform boost cut and back itself off. you may be hitting this, i would expect the engine check light to come on however

as stated in the original post the boost is set at 1.6kgcm2

yet boost is only making 21 psi! how would boost cut be activating?

does anyone have english instructions for the pfc boost kit?

i have posted the dyno graph in the original post

cheers

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • I know why it happened and I’m embarrassed to say but I was testing the polarity of one of the led bulb to see which side was positive with a 12v battery and that’s when it decided to fry hoping I didn’t damage anything else
    • I came here to note that is a zener diode too base on the info there. Based on that, I'd also be suspicious that replacing it, and it's likely to do the same. A lot of use cases will see it used as either voltage protection, or to create a cheap but relatively stable fixed voltage supply. That would mean it has seen more voltage than it should, and has gone into voltage melt down. If there is something else in the circuit dumping out higher than it should voltages, that needs to be found too. It's quite likely they're trying to use the Zener to limit the voltage that is hitting through to the transistor beside it, so what ever goes to the zener is likely a signal, and they're using the transistor in that circuit to amplify it. Especially as it seems they've also got a capacitor across the zener. Looks like there is meant to be something "noisy" to that zener, and what ever it was, had a melt down. Looking at that picture, it also looks like there's some solder joints that really need redoing, and it might be worth having the whole board properly inspected.  Unfortunately, without being able to stick a multimeter on it, and start tracing it all out, I'm pretty much at a loss now to help. I don't even believe I have a climate control board from an R33 around here to pull apart and see if any of the circuit appears similar to give some ideas.
    • Nah - but you won't find anything on dismantling the seats in any such thing anyway.
    • Could be. Could also be that they sit around broken more. To be fair, you almost never see one driving around. I see more R chassis GTRs than the Renault ones.
    • Yeah. Nah. This is why I said My bold for my double emphasis. We're not talking about cars tuned to the edge of det here. We're talking about normal cars. Flame propagation speed and the amount of energy required to ignite the fuel are not significant factors when running at 1500-4000 rpm, and medium to light loads, like nearly every car on the road (except twin cab utes which are driven at 6k and 100% load all the time). There is no shortage of ignition energy available in any petrol engine. If there was, we'd all be in deep shit. The calorific value, on a volume basis, is significantly different, between 98 and 91, and that turns up immediately in consumption numbers. You can see the signal easily if you control for the other variables well enough, and/or collect enough stats. As to not seeing any benefit - we had a couple of EF and EL Falcons in the company fleet back in the late 90s and early 2000s. The EEC IV ECU in those things was particularly good at adding in timing as soon as knock headroom improved, which typically came from putting in some 95 or 98. The responsiveness and power improved noticeably, and the fuel consumption dropped considerably, just from going to 95. Less delta from there to 98 - almost not noticeable, compared to the big differences seen between 91 and 95. Way back in the day, when supermarkets first started selling fuel from their own stations, I did thousands of km in FNQ in a small Toyota. I can't remember if it was a Starlet or an early Yaris. Anyway - the supermarket servos were bringing in cheap fuel from Indonesia, and the other servos were still using locally refined gear. The fuel consumption was typically at least 5%, often as much as 8% worse on the Indo shit, presumably because they had a lot more oxygenated component in the brew, and were probably barely meeting the octane spec. Around the same time or maybe a bit later (like 25 years ago), I could tell the difference between Shell 98 and BP 98, and typically preferred to only use Shell then because the Skyline ran so much better on it. Years later I found the realtionship between them had swapped, as a consequence of yet more refinery closures. So I've only used BP 98 since. Although, I must say that I could not fault the odd tank of United 98 that I've run. It's probably the same stuff. It is also very important to remember that these findings are often dependent on region. With most of the refineries in Oz now dead, there's less variability in local stuff, and he majority of our fuels are not even refined here any more anyway. It probably depends more on which SE Asian refinery is currently cheapest to operate.
×
×
  • Create New...