PC-Pro replaced old Powercard - Set to max fuel, still running lean at dyno [Archive]

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Bamajets

02-20-2009, 08:37 AM

Hello all, (I thought about just calling Tom, but I thought my issue may be of interest to others)

I've got a 1999 with a BRP MP62 that has logged about 60K SC'd miles. I was running the original Powercard with an O2 clamp which worked OK, but around-town drivability was never great. I decided to upgrade to the PC-Pro based on many positive opinions from this and the "other" forum.

After installing, I immediately noticed improved drivability, but the factory settings for the PC-Pro were causing a lean condition under boost on my narrow-band A/F gauge. I added fuel in the Yellow-Blue (maxed at 8) and some in the G -Y -R zones until at least my narrow-band A/F was showing rich under boost. However, I wanted to dyno it to make sure before I did any more track days.

At the dyno, my first two runs were all around 13.5 A/F. I maxed out the PC-Pro with the following settings:

G -5
Y - 8
R -8
Y/B - 8

I still could only see barely under 13.0 A/F for two runs. The car did not ping, but obviously this is not quite where I want to be. I don't feel too confident for my upcoming track days. I attached the best dyno run below A/F-wise. (can't seem to embed the graphs)

Some more information on my car:

1999 10AE, 90K miles (60K with Supercharger)
BRP MP62, BTB, 95/65 pulleys (5-6 lbs boost)
Moss High Flow outlet
TDR A/A intercooler
Mazdaspeed Header, stock midpipe, Roadstersport Exhaust
Stock injectors, fuel pump, FPR
New NGK BKR6E plugs

Some thoughts and questions:

1) I should not have been "maxing" out the PC-Pro with my setup and power level (177 hp), right? Others with my similar setup don't seem to need as much fueling on the card.

2) I really wish I had brought the old Powercard to the dyno to swap it out. I have reliably flogged the car through 5 track days with it and now I am curious what A/F I was running with it. It would also tell me if it my stock fuel system was OK and it was a PC-Pro issue.

3) The dyno guy recommended an adjustable fuel pressure reg. I know at my power level, I should be fine without it, correct?

4) My fuel filter is old (like 50K miles old--new one is on the way). Could this have really made much difference?

5) My air tube connections to the PC-Pro seem sound, even under boost. My PC-Pro is T'd into my boost gauge conn. My boost gauge shows 6 lbs under WOT so I don't think it is leaking anywhere.

Any other things to check? Is my PC-Pro re-programmable to deliver more fuel?

Thanks for any help.

-Dan

Tom @ Fast Forward

02-20-2009, 08:54 AM

socal pat

02-20-2009, 08:59 PM

At 90k miles you should look at the fuel pump and filter. I would not change the regulator, but instead change to a 190hp or 255lph Walbro pump. This would eliminate any question of whether you are providing enough fuel to the injectors.

Gman7007

02-20-2009, 09:23 PM

Bamajets

02-20-2009, 09:49 PM

First, where are you getting the boost signal from? Is the vac/boost connection at the Dummy Throttle Body?

Second, I can re-flash the PC-Pro for you, if needed, to make it add more fuel but, it should have been able to add sufficient fuel as shipped for 6PSI.

The answer to question 1 is possibly the most important.

Hey Tom, yes I am getting the boost from the dummy throttle body. As I read in another thread, I believe it is one of the older cast ones that did not have the leak issue I read about with the welded ones. That being said, should I pick up the air elsewhere? I may go for the re-flash if I can't figure out what else is wrong.

Bamajets

02-20-2009, 09:53 PM

I am fighting a lean AFR as well. Awaiting to install my AEM before I run hard. We have a similar set up except I have 100/65mm pulleys and you have an IC.

I have recently replaced the fuel pump and the filter was replaced before the SC (15K miles ago).

Where was your AFR measured at?

http://www.fastforwardsuperchargers.com/forum/showthread.php?p=16973#post16973

Pat & Gman: I have a fuel filter on order. I am running the stock pump, but i do have a Walbro 255 gathering dust which I could try. I did not like the noise awhen I had it and at this power level did not think I really needed it.

I believe I tap the air/fuel signal for my narrow band gauge at the O2 sensor wire under the dash.

Tom @ Fast Forward

02-21-2009, 07:43 AM

Normally, the problem you described is the hookup. The actual boost is higher than the boost gauge and PC-Pro sees and it puts in less fuel. If you don't have enough adjustability, return the card and I'll up the fuel.

jwalton

02-21-2009, 10:59 AM

Hey Tom, yes I am getting the boost from the dummy throttle body. As I read in another thread, I believe it is one of the older cast ones that did not have the leak issue I read about with the welded ones. That being said, should I pick up the air elsewhere? I may go for the re-flash if I can't figure out what else is wrong.

Pick it up at the back/top of the intake manifold. There should be a elbowed nipple there where the cruise control gets it.

Bamajets

02-23-2009, 11:08 AM

I'll investigate the different boost pickup location and see where that gets me. I may also send the card back in for reflashing. More to come...

-Dan

Tom @ Fast Forward

02-23-2009, 01:56 PM

I would be happy to do whatever it takes to make it work right for you.

MarkB

02-24-2009, 09:27 PM

re-flashing the card may fix everything - could be that its not offering enough gain. i'm running 105/65 and needed to reflash to increase the gain. there was no difference on my car when moving the vacuum tube from dtb to i/m.

Bamajets

02-25-2009, 11:16 AM

Thanks Mark for the information. I think it is a good idea to re-flash even if I see a boost/vacuum change.

Tom, any special requirements (packaging, notes, address) when sending back? I have the old Powercard, so I am still able to stay on the road.

Thanks to all who replied, special thanks to Tom. I'll update with results in a couple weeks.

-Dan

Tom @ Fast Forward

02-25-2009, 11:27 AM

Nothing special about the box. I will turn it around within 24 hours of receipt.

Bamajets

02-25-2009, 05:54 PM

It's on its way...UPS ground (insured).

Bamajets

04-24-2009, 01:18 PM

Thought I would update the thread for closure. It looks like the reflash corrected things, giving me access to more fuel. I now have a 105mm pulley vs. the 95mm. I am running below 12.0 A/F until about 6500 rpm when it looks like my injectors are wide open and I am maxed out. 180.3 hp on a hot day was the final number. I'll try to get the dyno plot attached later.

Thanks Tom for the great service!

-Dan

Tom @ Fast Forward

04-24-2009, 04:22 PM

FormerDatsun510Man

04-24-2009, 05:03 PM

Dan,

Once you post the dyno, I am also interested to know what settings you used on the PC Pro.

Thanks,
Bill

Godless Commie

04-25-2009, 08:18 AM

180 is about as far as you can go with stock injectors. They are probably not wide open but close to it. I'm guessing you are pushing 8-9 PSI now as well? If E-Cool actually worked ;), I would recommend a bigger pulley and ECool.

I'm a bit confused here..
I am at 190 WHp.. Does that mean I have reached my maximum power level with the stock injectors, as well?
Tom, you had mentioned a possibility of well over 200 in my case (110/65 combo, TDR, E-Cool, BBK t/b), should I just forget about it then?
I was under the impression I could "go places" with a Walbro 255 pump, and adjustable FPR, and your hi flow rail.
Like I said, I am a bit confused. :confused:

tann3r

04-25-2009, 08:36 AM

Bamajets is not running E-Cool.

E-Cool, the 5th injector, supplies the additional fuel to support more power.

Tom @ Fast Forward

04-25-2009, 11:26 AM

Yeah, what Colin said. :)

With the 5th injector (the size of 2 stock injectors) 225/230 is not out of range.

rins

07-08-2009, 11:01 AM

I'm a bit confused here..
I am at 190 WHp.. Does that mean I have reached my maximum power level with the stock injectors, as well?
Tom, you had mentioned a possibility of well over 200 in my case (110/65 combo, TDR, E-Cool, BBK t/b), should I just forget about it then?
I was under the impression I could "go places" with a Walbro 255 pump, and adjustable FPR, and your hi flow rail.
Like I said, I am a bit confused. :confused:

With AFPR you can raise fuel pressure and make those injectors shoot more, thru reaching higher whp.....