i see that most of the maps are changed in the injector duty. do i have to change the leading and trailing or do they change respectively? do i have to let my car idle after changing maps? your thoughts.
kris

 

What is the goal that you're trying to accomplish?

 

well i just picked up the PFC used. i reset all and went back to the base map. i have an apexi intake, RB dual tip, and hks dp. im looking for a reasonable map that will control this on the safer side. also i have played with it and can not control boost very well. i have it set for .70 and .85, which from my conversion are pretty close to 10 and 12 lbs. they creep a lot. i dont see the car learning it much. any insight? i think i may just take it to the dyno shop and let him toy with it. for now though, what can i do?
kris

 

I think the base PFC map should be safe for your mods.

Have you tried adjusting the duty cycle with the boost level? It should change your boost response.

People get boost creep when the intake and exhaust is opened all the way up that can only be fixed by adding restriction and/or porting the wastegate, but I don't think that is your problem. Boost creep can be identified by the boost control working fine in lower gears at lower RPMs, but in high gear the boost rises despite the wastegate being fully open because it can't flow enough to control boost. I believe that you have a boost control problem that causes the boost to rise over the pre-set level (and could thus be called creep), but I think it is a control problem rather than a mechanical limitation.

-Max

 

do you thing that i should remove my pill in the line. i remember seeing it and putting it back in when i did the silicone hose job. any other tricks that might work max????? thanks max and others, you guys are so helpful.
kris

 

Hi superfast, I just got a PFC as well...it came bundled with the base map from the RX7store.net...Jason said that the bas map will be fine for IC, DP, CB, & MP...Tuning will be needed after the MP install though...However I think I am going to have someone do that for me...

 

max, you mentioned injector duty cycle. what do i need to change that to. right now under the boost option i show
PR .70 54%
SC .70 64%

PR .85 62%
SC .85 70%
i played with them to make them 10 and 12 pounds but it seems to not be working at holding the boost. here is injector data if it means anything
100% on all options with 0ms in time. this is the version i am running also
PFC=5.08 and commander is 5.00A.
if there is a new BASE map that i should go with let me know. i just dont want to spike and i want to get everything set up for this weekends autoX.
kris

 

Hey Superfast,

The "base duty" is what the PFC starts with everytime you get into boost. PR is actually the duty cycle on the precontrol gate and SC is the duty cycle on the Wastegate. The PFC will adjust this a little bit to try to hit your target boost, but if you have them set too high, they will look a lot like boost creep. Each system is different.

for your second setting try something more like
.70 42%
.70 54%

.85 56%
.85 64%

and let us know how it goes.

oh, and leave your pills in place.

 

cool, thank you very much. i will let you know how this goes. id love to see the computer regulate boost the way its supposed to. also, whenever an electrical load is put on the car the idle surges. it will fix itself in about 20 seconds after the load was put in place. lastly, how do i set the PFC to kick the fans on at a lower TEMP?

 

You need to buy or borrow an FC-Datalogit (www.fc-datalogit.co.nz) and use a laptop to change the fan settings. But if you do that there are a bunch of other features you get. Either that or send the unit to a Power Excel Dealer (XS Engineering or SR Motorsports)

 

If you are lowering or increasing the boost with the PFC don't you have to keep the duty cycle the same ratio that it started out with...like for instance I got my base maps with the

PR at .80 and 56%

so if you divide .80 by .56 then it's 1.43...so for the PR if you lower it to say .70 then the duty cycle would be

.70 x 1.43 = .48 or 48%

PR .70 and duty cycle 48%

My math may suck *** but is the idea to keep the boost consistent with the duty cycle? ie. if you raise the boost then raise the duty cycle...if you lower boost then lower the duty cycle? Right? If I am totally wrong is there a formula for calculating this?

Thanks.
David

 

That's the idea,

But each car is different, so for .80 56% may produce spikes on one car, and lagging boost on another. The first car would reduce the duty to achieve the same boost level and the second would increase it.

With the Datalogit you can log the PC and WG duty cycle, and watch the car adjust the duty cycle to determine what a really good base duty % is. For example if it started at 56% but then rose up to 64% and held, that would be a good indication to raise the base duty.

 

so if we set out overall boost to one point(.70) and it rises to .76, would we just lower the inj. duty till it only hits .70ish?
kris

 

No.. you need to adjust the percentage on the solenoid duty cycle. You are not doing anything to the injector duty when you are playing with the boost settings.

 

oops, thats what i meant
kris

 

I figured you did.. too much stuff to play with on the PFC to keep it straight all the time.

I'll have to look you up in December, I'll be cruising the FD up to Modesto to visit my parents for the holidays.. that is if I get the thing started by then.

Matt

 

sounds sweet man. my buddy and i would be more than happy to run terror on the streets of modesto.
kris

 

Ok, so if I want to knock the boost down to .5 (for my #1 setting) then I should decrease the %'s as well.

How does this work with a Profec B? (which is still giving me 10psi with all of it set to min....aaarrrggg)

I am trying to get my car to 7psi with all the gizmos I have and then start adjusting up from there. I can't figure out where the 10psi is coming from...

Any thoughts?

 

Coop.

Stock turbos and wastegate? If not, what spring are you using? You might be on the wastegate's lower limit (if single turbo).

 

Yea, stock turbos and WG...I was wondering if the WG was slightly open in 1st gear to let out the exhaust...and then in higher gears the WG gets closed...is this possible?

Is there a way to see if the Profec is working? (I did get it used)

 

Also, here is my list of mods...

 

I don't know the profec very well, but there are two things to think about.

1) Ive heard that if you turn the profec off that you will just get the wastegate spring - or 7 lbs. Maybe give that a try.

2) I've seen two different install instructions - one with the profec t'd into both the WG and PC actuators, and the other only into the WG. The second is - I believe, the correct way to operate, but then you are not really controlling the bost on the first turbo (<4500). The PFC would still be doing that. In this case reduce the target boost to .5 on the primary trubo and the base duty % to something really low.

 

but if you reduce the boost on the primary turbo, won't the PFC cut fuel when it sences .25 kg/cm higher than the setting?
so wouldn't you want the primary set high to advoid fuel cut, and then the secondary set to a reasonable value?