Heres a short clip after I recorded a boost run. Stock sequential in good working order. Std PFC boost control (no boost control kit). I think the onboard PFC boost control works quite well once you have played around with the duties. My duties arent far off the stock default values. there is a bit of change between winter and summer but I just set two diffrent set ups for summer and winter. first gear primary doesnt get to the set boost of .90 bar but thats pretty common but after transition its very consistent.

http://s42.photobucket.com/albums/e3...fdboostwmv.flv

or

 

kerry have you tried to change the transition RPM point?

 

yeah I changed the low settings but the high is still the same.
I think its set at:
3600
3520
3520
seem to work well for my mods.

 

thanks....

the reason I asked was that I got to ride in a stock working FD and the Primary seemed to spool up much quicker and at a lower RPM than my car with the PFC.

My sequential system seems to work perfectly with 10 9 10 setup on low boost with 99spec turbos.

Right now, they feel like I am in a car with a single despite the faster spinning primary.

Have you dropped the low setting to 3000 or less? I was thinking 2500.

 

I thought the "low" setting affects when the twins go back into sequential mode after switching into nonsequential mode? how would that really help spool in your situation?

 

I have not experimented with this as my engine was non-seq when I got my PFC back in 1999. According to a few, dropping the high rpm point by about 500rpms helps with transistion from 1 to both turbos with modded engine.

I have not read anything about lowering the low point.

 

eh crap...let me re-read that section in the manual.

for a working sequential, the car just feels "laggy".

Chuck, I probably need to set up a weekend with you to give me the PFC tutorial and tune the PFC.

 

Have you dropped the low setting to 3000 or less? I was thinking 2500.[/QUOTE]

Have tried lowering the low setting less than 3000 but what you get is a big flat spot/lag when fast shifting, when revs has gone passed the 5000rpm and revs doesnt drop down low enough between shifts.....worse on freeway speeds. Istill get that flat spot with the 3000 low setting and the 3500-3600 seem to work very well for me.
mods are:

3in d/p
m/p
catback
Greddy SMIC
HKS RS filter
PFC

Chuck knows plenty than most people in the forum when it comes to PFC and FDs
wish I live around the corner from him. He sent me his seq map a while back before I had my DL and would have liked to use his map as starting point for tuning but my PC crashed and I lost that map . I think he got 350rwhp+ from that map

 

many thanks...

I am going to make sure the precontrol rod is set correctly.

 

The turbo transition works by switching from sequential to non-sequential mode based on the RPM and the throttle percentage. The confusing area is the “Low” and “High” in setting 1 of the Datalogit software. The low and high is NOT the low and high point the RPM switches on and off the sequential mode; rather, it is the setting for low and high BOOST CONTROL settings. An important key to note is that the high rpm settings need to be higher than the low settings—if not the higher of the rpms are chosen. The on and off are with respect to the RPM setting and the TPS percentage setting. I have below a pic of what happens at the TPS % and RPM for my current settings. Also below that is a pic of my settings.

I'm putting together a write up on this to better explain the transition confusion when I get a chance.

 

wait, what does TCN mean?

 

Turbo control valve ...don't know why there is a "N" after TC

 

Thanks Nashman....that write up would be great.

 

If this is right, it is very helpful! Nashman, What is the low and high boost control that you refer to. I assume if I have and EBC the low and high boost control would have no effect because boost is controled by the EBC, but the transition settings would still control the opening and closing of the TCV. I know how most all of this turbo system works, but this setting has still confused me. . .I look forward to your write-up.
--Jeff

 

Yes, the boost control is for high and low boost settings that , because of your EBC, have no effect for you. The transition settings would still work for the TCN though.
If you look under "boost control" in the above pic, there is a 1 and 2. This is for low and high boost, respectfully. So for your case just make sure that you have the settings you want in the appropriate column of the transition control. If this is confusing, sorry.

 

I had time to work with this over the weekend and just want to report it's as if I have a new car! I've been working with the turbo transition settings since I got BNR stage 3 (sequential) and the car just hasn't been quite happy. I don't know whether it's because the BNR primary pulls better than stock or what, but the settings above (4,000 5,000 6,000) give me all the power I need when not at full throttle, yet really brings it on when I do hit the throttle. Basically, I have noticed since getting the BNR's, when not at full throttle all sorts of weird s__t happens once you enter transition. ..it's like it just doesn't know quite what to do. Also (could be my imagination) it seems the transition is much quicker and smoother (I use profec b, type s EBC hooked up in "type 2" configuration for those that have this controller with sequential turbos). Anyway, thought I'd share since this has made the single biggest difference in anything I have done for really getting the BNR sequential setup to perform well.
--Jeff

 

so for a sequential FD running about .90 boost (for the high setting) on stock turbos, using the PFC to control all aspects of boost control, would you guys recommend trying the 4000-5000-6000 combination?

 

As with anything, try at your own risk, but I would say give it a shot if you are unhappy with your current transition. Not sure if the result will be the same with stock wg, ps and turbos, but it appears nashman is using the stock boost control system above. I never tried this setting with stock turbos, so I don't know if the stock primary will carry the load to higher rpm's under lower throttle percentage. Let us know how it works out. . .

 

try my settings first...My peak boost with my settings is 12psig. I have stock twins with CAI, 3" straight exhaust all the way and of course the PFC. My maps are unchanged(stock Apexi maps). I find that I'm running rich under boost. Be careful and take it easy though to be safe. I haven't fine tunned the transition numbers but they work pretty good for now. Try the settings I have for boost 1. If you want more boost or less just tweek the primary and secondary numbers in small increments.

 

Just to clarify (and I have searched!):
The normal PFC can control boost on a stock sequential FD, right?
If so, is the boost control kit simply to improve response?
Cheers

 

The PFC controls boost the same way the stock ECU does, but gives you more flexibility to set the duty cycles that control the wastegate. An aftermarket EBC takes one or both of the wastegate and prespool solenoids (depending upon how you set it up) out of the system and regulates boost based on real-time feedback as opposed to static duty cycles. This is a very basic explanation, you will find more on here by searching and reading, but it is hard to find everything in one spot sometimes.
--Jeff

 

Ah cool. Yeah I get what you're saying. So it's a pre-programed response that the system has to controlling boost.

That is - it doesn't have the negative feedback to control boost in real time like an EBC. Thus one might expect it to overboost in the cold and underboost during the hotter weather?

Do people generally find it works well?

 

It basically works as good as the stock system did as it uses the same solenoids, it just allows you to set it where you want it.

It should be fine if you are modded alot and don't want to run a lot of boost. An aftermarket controller is just more sensitive and designed for the extra pressure where the stock system wasn't.

 

Question. So I gather I can control the boost on my '99 twins with the PFC. Maybe not the best but it works. So if I were to buy the boost controller kit for the Apexi would it be beneficial? Would it provide real time control or just provide new solenoids for the same function that the PFS already provides? I am looking to get the boost as high as I can while still being "reliable"

 

PM'd you.

:-) neil