PFC settings for 850CC primaries?
 

I am thinking about using 64.5 and 0.04 for the 850cc primaries. I tried 100/-0.04 but idled like caca.

Suggestions? Experience? TIA!

If you follow the instructions on pages 25-26 of the manual and it is too rich or turbo transition is crappy, then you will need someone with a DATALOGIT to tune the PFC. There are older post about this out there, search for them.

search on "850cc primary" and other purmutations yielded nada

I remember seeing the posts, but can't find them

Thanks Chuck. Two of the injectors are actually your olds ones!

Tony

For those that are wondering or searching in the future, here is how I got my numbers for the PFC:

550cc/min have a lag time of .73
850cc/min have a lag time of .76
Lag difference = .76-.73 = .04

Injector size adjustment = 550 / 850 = 64.5%

My search of 850 retrieved 20 posts, with about 16 being about injectors and not 850rpm.

One had these calculations for 850 primaries.
64.7 % with +.05 lag correction.

The 64.7% is mandatory with 850cc primaries. Just entering 850cc in the other box will not cut it. Now lag is a different topic all together.

Oh yeah, now I am getting alot more returns on the search. I was only getting about 6 before, and all the posts were current ones.

I am thinking someone fixed or changed something. I re-excuted the same searchs and am now getting more results.

Without adjusting any other settings (other than the 64.7 and .04) I am rock solid.

Did you enter 850 as the primary injectors? If not the then the staging of the secondaries will be off.

850 as primary. Transitions are smooth. Staging seems on.

How's it feel at throttle tip in?

Tim

Silky at tip in. No difference from the 550/850s.

My settings from ACCELERATE INJ (MS), SETTINGS 2 from the datalogit:
RPM AMT DECAY
5000 7.5 1
4000 7.5 1
3000 7.5 1.5
2000 8.0 1.8
1000 6.0 2.0

I hate the stock acc inj settings. I lean out the top end and make the curve smooth from 1000 .... ie 7.0 to 7.5 for 5000 to 1000.

Another question, what's the injector duty cycle at now with the 850's in all four at whatever boost you are running?
Thanks for the info on the 850 setup, lag time, and accel enrichment times. Good stuff to know.
Tim

I hit 70% running 1bar during some wideband tuning. That is with the 850/1300s and a walbro HIFLO in the tank. I am thinking about replacing the stock regulator with a SX 1:1 unit and adding a fuel pressure gauge. At little overkill for the stock turbos...but I am thinking of it as prep. for the a single...some day. ;)

bringing it back from the dead for people to use.

Tim

Has anyone needed to change the cold start enrichment settings?

No, but I had to play with crank time.

Can we discuss a little about the crank time and what it is actually doing? I havent messed with it but feel like I prob need to, dont really know much about it and couldnt really find any info on it though

STEPHEN

I'm running 4x 850cc with settings for primary injectors as 65.0 w/ .04 lag correction...
Car idles rich (low 11's A/F) and by changing the lag time to -.08 I was bale to lean out idle *but* accelarations were running much leaner...so I went back to .04.

Boostn7,
Have you tried just leaning out the cells at idle to help get rid of the rich idle? If so, what happened?

Tim

I'm also running a/f at idle of 11.0

Actually I've noticed that anytime I'm barely touching the throttle or sitting at idle my af is around 10.8-11.3. I thought maybe the air bleed screw was closed off so when the throttle plates were close there wasnt any air but I opened it almost completely and it didnt really help much. My idle did smooth out some but it didnt really help my af much. Its still low 11's. I've pulled out quite a lot of fuel from idle, I'm going to try pulling more just to see if it will help, but I've pulled a TON.

I'm also running the injector settings above.

Are you guys running O2 control???? I've got my O2 sensor unpluged, maybe I should plug it back in and let the PFC try and control it.

DOES ANYONE HAVE A NICE SMOOTH IDLE AND 14ISH A/F RATIO WITH 850's???? If so what is your exact set up? have you blocked off the idle control or is it still in tact?

STEPHEN

Good question Stephen, hopefully someone has some datalogit info on this or parameters for us to use.

Tim

I run both the FJO wide band and a 4-wire O2 sensor connected to the ECU.
@ idle it still runs in the low 11's so I assume the O2 sensor does not get involved with idle unless there's settings for it.
but during cruising/coasting I see A/F's in the 14's.

There is a setting concerning the O2 feedback loop, is it on for feedback or is it turned off, meaning it just reads off the maps and isn't in lean run mode at idle and low loads, part throttle driving?

Tim

I see 14's at idle, it is smooth'ish, but I had it smoother in the warmer weather. I think I know how to get it to rock-solid 750-800 without much of a waver, but I have not had any time to get to the car for a bit. It's ski season you know!

Again, a good tune should include temperature correction AND a good idle. A really good tune will give you passable MPG in freeway driving/crusing conditions.

If I give you parameters for idle and cruise, Stephen, I want a larger credit! :D

Well, Steve couldnt help it I ran out of dyno time. My WOT a/f started out in the 7's!!!!!!!!!!!!!

You must have added some "extra" fuel haha

It took us a while to get the a/f in place then I started running out of money haha

BTW - Its wierd cause my idle is actually decent it just is very rich, I mean its not glass smooth but its ok. And I'm actually getting about 20mpg on the highway which isnt bad either!!!! My cells that are rich are the P1 - P4 cells no matter if I'm driving or sitting and it seems when I pull fuel it doesnt really help.

Anyway, any help you can give as always is appreciated. I'll have to come up with some name for my map to give everyone credit HaHa

If you dont mind showing me some settings I can at least compare them with what I have to see how bad off I am lol

Oh yea, if you want to email me anything my address is SJWhite2000@aol.com maybe I'll come cut your grass this summer or something hehe

STEPHEN

Stephen,

If your cutting his grass, I'll wash and wax the car then.

Not that I would try to organize anything right now, but that barber museum race track is looking sweet over in Birmingham...wonder how much it is to rent for a day...wonder if its cheaper than Road Atlanta, which is up to $10000 per day plus your left leg, right nut and ear lobe last time I checked out their web page. Almost like Panoz wants to pay off his road atlanta purchase early with the amount he charges.

Tim

Just catching up with this thread ...

My idle AFR is now in the high 12 low 13, any leaner and the idle gets rough. Can still pull another 5-7% fuel out of the mix at idle but it gets too rough and throttle tip-in gets lean, would need to adjust accel enrichment. The idle speed control is disconnected, doesn't control idle speed and not worth replacing. Idle is steady and consistent with manual adjustment.

Question for those running O2 feedback, if I turn it on it will attempt to go into closed loop at all low throttle input conditions including idle! Frustrating as hell as it will die at idle conditions, would like to run with it on to improve cruise mpg. Cruise AFRs are in the 14's.

Geez, the guy breaks 400rwhp, then wants smooth idle?
 

Ok, I want to play since I plan on going 850/1600 to keep up with Stehpen :-) A couple of questions to ask - are you tuning your idle with or without a smog pump? If you have a smog pump, where is your wide band sensor in relation to the air pipe for the cat?

For me, I've retained the smog pump, and the air pipe is BEFORE the sensor. Therefore I get additional air when the pump is on, so my afr is not indicative of what is truly going on in the motor.

If this is how you are set up, you need to disconnect your air pump switch when you tune the NA area.

I'm using 550/1300, and with the air pump off I'm finding that right around 13 afr at idle is nice and smooth (I have o2 feedback turned on). Anything leaner gets lumpy, and anything richer than 12.5 gets lumpy.

Basically tune the na area with your smog pump disconnected to get the best readings.

Sorry I don't have any 850 specific stuff. Thanks for paving the way.

Beast

PS - Tony - I sent you an email re: voltage issues with the DIY wideband. Please check it out - I know you can help me!

Edit - SPO, it's not surprising that you have to pull out a LOT of fuel with 850s. That's a big jump from 550. In the upper rpm na range I'm running corrections as low as .875 because of the 1300cc injectors.

70% duty at 1 bar? Seems high
 

Tony - I'm only seeing 56% at 1.03 kg/cm^2 (1 bar) with an afr of 10.08. It's in the '130mph' log I sent you, check time 116.698. At 70% you should have been choking in fuel.

?

(I'm just trying to get you to look at my an1 vs. an2 voltages for my wideband:D But seriously, those are my duty cycles. I'm using 550/1300 setup, too (although rc flowed them at 1350).

Beast

I've ditched the smog pump a long time ago and I've got most everything striped from the uim. I'm basically running manual idle, ect.

My wideband O2 is in the end of the dp next to the mp. I watched it what on the dyno and it was really close, within .1 most all the time!!! Which is good considering thiers was $5000 and mine was $400 lol

I also checked the idle a/f on thier wb and it was right around 11-11.1, it stays like that till I get into P5, then it clears right up to 14ish. Its wierd cause the inj settings arent that far apart from P1,2,3,4 as compared to 5, they are lower and in stages but for somereson as soon as I get to P5 it clears. This is no matter what rpm from idle to 5K it wont matter.

Thats why I though the air bleed screw was closed and it was just choking when the throttle plates were closed. But I opened it all the way and it made no real difference. Then I started pulling a ton of fuel and it sill made no real diff.

I have noticed sometimes though at idle its at 14.7 but thats cause my rpms are so low and the alt is off and its not getting enough volts. Maybe some of you guys running 850's with 14a/f just dont ahve enough volts and the display is just showing 14.7. Is that possible???

STEPHEN

STEPHEN

Re: Geez, the guy breaks 400rwhp, then wants smooth idle?
 

Stephen,

I think it's power or more precisely, not enough juice for the heater circuit. Especially the colder it gets out.

Tony

Yea, I agree I've noticed that in the cold weather when my coolant temps are like 83C and the air temps are like 10C or less my display wont show a/f readings cause the heater isnt getting warm enough.

So, Tony are you actually getting 14ish a/f when in your P1-P4 lines??? If you are I'd like to compare some settings or something. There must be something I'm doing wrong.

Do you have everything striped off the uim? I know your air pump is gone. What about closed loop? You still running that with the O2 or is it gone as well? What do you set your O2 control at? on or off?

Thanks Tony,
STEPHEN

You know, it's been so long that I'll have to retest it again. The cars has been sleeping for 60 days. Well deserved rest.

NB O2 on, IGN and FUEL control on (can go into closed loop).

UIM is missing....um...the thing under there that gets in the way when doing the injectors.

I didnt know your cars been "resting" for 60 days now!!! I'm sorry to hear that but I know you'll like it all that much more when its back up.

I have a feeling your getting the good a/f ratios from the closed loop. For some reason I cant seem to control the injectors for that small amt of fuel.

If I have the O2 control and ign control off then PFC should look to the maps for all the fuel and ign info......right?

STEPHEN

Right. Disable the control and idle is all yours to muck with.

Car started on the first key turn, even with old fuel in it! Not a good way to store a car for the winter, but DAMN!

Tony

WOW, these are some OLD threads but its good they came back to life cause I have some info to add to them.

I could never get my idle super smooth and it was so rich you couldnt stand to be within 15 feet of the car while it was cranked. I had my O2 disconnected and the O2 and IGN control turned off.

Here is what I found, even with the O2 and IGN control off the PFC STILL messed around with it at idle. My guess is that its looking for a O2 reading to make these corrections with but since mine wasnt hooked up it just treated it like it was super lean. Actually I didnt have my O2 hooked up but when I looked at it in the PFC is shows .03 like its just SUPER lean. So my thoughts are that the PFC is seeing this .03 reading from the O2 eventhough its not hooked up and dumping insane amounts of fuel.

I hooked up my O2 and the car idles perfect just like it did (or better) than the day it came off the line. Standing at the back of the car you can barely even smell any exhaust at all.

I now suggest to people that they need to keep the O2 sensor and just let the PFC control the idle settings. It does a good job so why not, its just one less think for me to screw around with.

STEPHEN

Interesting. I have my O2 in, but the control for idle and IGN is off. Before that I had a "tear-jerker" idle too. Nothing like watching everyone in traffic get teared-eyed when at a stand still.

Tony

Yea, its wierd. For about 3 months I ran with no O2 sensor hooked up at all and I tried turning the 2 idle control setting off, on, turning on off and on one then swaping them, I tried it all and nothing made any differance at all. I could pull everysingle bit of fuel out at idle and my a/f and inj duty would ramain the same. I could adjust the timing to anything and it would stay the same.

I finally just pluged in my O2 and all was perfect. I did notice though that when my o2 was disconnected I was still getting a PFC O2 reading of .03. I'm thinking because of this the PFC thought the O2 was hooked up but just running extremely lean. Maybe there is built in software that if its a certain amount lean or rich the PFC takes over no matter what settings its on. I have no idea, just sharing what my experiences were.

Go figure
STEPHEN

Once you changed it to 64.7 / .04 for the 850 primaries, did you have to change the 20x20 bsse map or 20x20 injector map numbers?

Thanks

And, if you do have to change these two maps, what do you use/go by to do it?

Thanks

Does anyone have a datalogit file for a 850/1600 setup for a 3 bar map? That is all I'm missing for a tune!!! :)

I have tuned a litle different than what was said prior. I set my 850s at 82% and -.4 lag
and 1600s at .6. I leave the stock map alone until I put these setting in and then go after the fuel map. I find the acceleration is better and and you dont have to change as much on the base maps. I have and eddy current dyno and also run a wideband FJO in my car. I have played around with all different combos on fuel settings and found for my customers cars and my own they run the best. Why the settings work so well I cant say because
they go against the PFC manual. We run street twins up,- GT42r turbo setups
all this way. Just my 2 cents.

Here's my current setup:

NEW engine with 5K miles on it
ARC SMIC
'99 SPEC intake duct with STOCK airbox
Supra TT fuel-pump
Efini Y-Pipe
JDM downpipe (no pre-cat)
High-flow metallic cat w/air-tube
Magnaflow resonator
TRUST muffler
PFC with RX7Store BASE (non-dyno) tune for the above mods (injectors at 80% duty-cycle at WOT)

currently idle surges when below 40-F, otherwise fine

Would you recommend 850cc primaries ?

Also, I plan to make the 5-hour drive to Petit Racing for a Steve Kan tune.

What minimal settings on the PFC should I do, if I install 850cc primaries BEFORE my tune and for my drive ?

TIA,
:-) neil

just check the beginning of this thread, but 64 or 65% with .04 lag, set the primary settings to 850 from 550 and it should run.

Im currently having 850cc primary idle and starting problems. What did you do to the cranking times. A friend has told me i need to alter them

Scott

I never had any problems with starting or idle using 4x850cc injectors at stock pressure. I did have enough fuel in my oil to make a mess in my intake from overfull oil. I have since taken a lot of fuel out of my maps and reduced my cranking times to reduce the likely hood of this happening again. I found the 7 still started fine with the following cranking times...

Cranking (ms)
+80C 9.0
+50C 13.0
+30C 24.0
+10C 44.3
-10C 65.4
-30C 67.4

I haven't done much testing at a wide range of temperatures but this has worked for me so far. Your mileage may vary. Post back how they work for you if you try them.

Thanks for everyone's help!

I nowhave 850cc in the primaries, and she started right up after the adjustments, and is idling great.

Off to Pettit for a tuning with Steve Kan!

BTW: typically how much boost can I safely run with these injectors and the stock twin-turbos ? 13-14 psi ?

:-) neil