I've just started my real tunning with the link 2 and turbo. The car bogs severly at 3500rpm and at 4500rpm and at 5500rpm. It almost feels like a revlimiter. So I start leaning it out. I decresed those zones by about 60 and it still bogs, but not as bad. The egt's during this time keep going down. Then I take a look at my O2 and it is reading stoich. If I was stoich I would be pining hardcore and I'm not and the car still bogs. So tomorrow I'm gonna run out to autozone and pick up a narrow band z28 bosh O2.

-Chav

At what Kpa range and what kind of timing are you running?

130kpa max and 8-12 degres over the base 10 between 2000-3500 and then up to 15 over the base 10 to redline.

-Chav

I think you may not be running enough timing..

Try 35 degrees of timing by 2500 rpm and ramp down to 30-35 degrees of timing after 4500 rpm.

Are you sure? The stock timing map goes up to 28-29 degrees at redline. So I decided to take that and retard the timing a little bit. That is how I came up with my 25 degrees max at redline/WOT. The map you attached; are those the values before or after the built in 10 degrees advance? Thanks for the suggestion, you may be right though. After I posted I thought that maybe I am running stoich, a very scary thought.

-Chav

Its a base Tec ignition map for a MY00 RS-T running premium gas.

Take the values and approximate them for your rpm curve and take out the 10 built in and plug that in.
Ignore or approximate the values at 110Kpa and up. They are extremely conservative.

Don't forget to listen/feel for knock.

Thanks Revision I will try that.

-Chav

Edit: Your numbers in that map are close to what I'm running. Your map has 14 degrees of advance at 3850rpms and then up to 24 dgrees of advance at redline. I'm running 18-22 degrees of advance (including 10 degrees built in) between 2000rpm and 3500rpm and then 25 degrees to redline (including 10 degrees built in). Let me know if I'm missing something. Thanks

I just went out and picked up the Z28 O2 sensor today. Slaping it in tomorrow and I'll see how big the difference is.

OK. I tossed in that Z28 O2 sensor, but the readings are not all that different. It did say that I was running a bit leaner that what the stock O2 said. My big concern is that the reading is still all over the place. I would like to know if this is common, or is my tuning way off, or is my sensor hooked up all wrong?
My understanding was that the Z28 O2 would not drop off like that. I also did not get the Boch one. It's some other brand, but it still was not cheep.
Here is a screen shot of the O2 reading (O2 is in blue)
http://home.pacbell.net/punkidd/o201_web.jpg
And yes I did see that spike in the Knock count. I blasted off from a dead stop. I'm guessing that the IC was a little hot from sitting there for a while. Can that be adjusted for w/ the AAtemp sensor setting?

Chav,
Sorry about hijacking your thread.

I just picked up the O2 and I'm about to install it. It is part number 15703. 50 bucks.

Punkidd, your run time plots look like mine. When I first dip into the throttle the a/f goes lean and then comes back. The only thing that is different is that once the a/f comes back it usually holds it's value. Your's jumps up and down a bit.

-Chav

Yeah, it is that jumping that bothers me. It doesn't seem verry acurate that way.

Just got done tunning for the day. I don't think the camaro O2 is any better than stock. I fixed the 4000-redline harsh stutter, but I don't know how. I just started yelling at the laptop and changing a few things and it works. :confused: I still have the 3200-3500 rpm stutter, but I will do some more yelling tomorrow.

One quick question. On the configuration should the priority be cyl or sync? Thanks

-Chav

Default from AMR is synch.

thanx Midwayman!

-Chav

Another couple hours of tunning and I'm running at 97% IDC @ 4.5psi on stock injectors, dual feed fuel line, and walbro fuel pump. I'm not running incredibly rich because if I lean it out it pings. My timing is very conservative it starts at 12 degrees of advance at 2000 rpm and reaches 18 degrees of advance by 4000rpm and then slowly increases to 25 degrees of advance at redline (all advance numbers include the built in 10 degrees). I thought i'd see 97% IDC if I was running 6-7psi, is this normal? Also the EGT's are 55 degrees ferinhight above stock. Stock was incredibly rich at about 1436 @ WOT redline in 3rd from 25mph. Now under the same run it is around 1500 F.

-Chav

P.S. What range of BSFC should I expect for my car?

Originally posted by Revision
I think you may not be running enough timing..

Try 35 degrees of timing by 2500 rpm and ramp down to 30-35 degrees of timing after 4500 rpm.

http://forums.i-club.com/forums/attachment.php?s=&postid=2463122

So simple, it should be considered a toy!! :lol: :lol: ;)

If you don't run enough timing, you will see higher than normal EGTs. If you run too much timing, you will start pinging.

Keep timing close to stock while off boost then go real conservative while on boost. Once that is done then start slowing increasing timing.

Yeah, I've got the Haltech holding timing in the 'safe' range right now and see generally higher EGTs. I think it's due to the combustion happening just as the exhaust port opens and causing some flash in the exhaust manifold?

Was that 97% duty cycle? That's not a good thing. IIRC You shouldn't be going past ~80% duty cycle on injectors unless you like taking chances.

My narrow band seems to do an OK job. The only times it gives me bad readings is when the ground to my A/F meter comes loose. I always compare A/F readings to my EGTs and they always seem to agree with each other. And with how rich I've been running lately (like .85v) you'd think the O2 sensor would start sliding.

~Garrett

What voltage are you tuning to at idle with your master fuel value? Or maybe I should just ask what master fuel values people are using along with fuel pressure and injector size.

Garrett: Ya, I believe that is what happens when you retard the timing. Yup, 97% @ 4.5psi, I need new injectors bad.

Midwayman, the voltage I aim for at idle is .7v with my master fuel at 110. Stock injectors, walbro fuel pump, stock fpr, and dual feed fuel line.

-Chav

I aim for .835 idle voltage, though I don't know why. It still seems to work well. Maybe my O2 was already reading on the rich side.

How are you getting 97% duty cycle on 4.5psi? I'm running stock injectors on 5psi (was 8psi in the mountains) and only get up to 85% duty cycle. What would cause them to peak that high? Like I posted in another thread I've got 45k miles on the turbo 2.5 and haven't had injector problems even when I was running piggybacks. Now I can easily log peak duty cycles and I'm still not running that high. There might be something else going on like one of them gumming up or something?

~Garrett

I think something maybe wrong. They hit 97% at around 5500 rpm and hold that to redline. Without the turbo I was hitting 85% IDC with the stock ecu (I have a IDC monitor). Now with the Link it shows 97% as does the IDC monitor. Hmm, this brings up some scary thoughts. Such as if one injector is stuck closed/not firing correctly than the others have to dump a lot of fuel in to get the a/f ratio at the o2 sensor correct. That doesnt make sense though since my EGT's would be threw the roof with all the extra fuel. The egt's are hitting 1500 F at WOT/redline in 3rd from 25mph. Stock they hit 1440F. Also the injectors hitting 85-90% IDC with the stock ECU leads me to believe that they would be maxing out with 4.5psi. Also if one cylinder was running lean from a stuck injector the knock sensor would pick up the knock, but it doesn't pick up anything (just engine noise). If I was running really rich than when I pull fuel out it shouldn't ping, but it does even with my conservative timing and the EGT's go up. But after considering all the worse case senarios the one that makes the most sense is that the stock injectors just can't support 4.5psi. With the fuel worksheet on www.rceng.com it indicates that the stock injectors are good for 210-230hp based on 48-54 psi fuel pressure. One thing did cross my mind though. Garrett, you have a 99 right? Do the 99's have the same size injectors as the 00-01s (280cc)?

-Chav

I'm getting into the 90s on 4.5 too. I just assumed that it was the FMIC causing a more dense air charge. I'm also in the bay area so I'm right at sea level. Does that make sence?

Yea, being a sea level the air is denser (denser even a word?). I'm at sea level as well. I'm going to change the plugs tomorrow just in case since they are so cheap. I don't really understand what could cause the injectors to run such high IDCs. I just looked over some old datalogs when I was n/a with the Link 2 and the max I hit was 82% and most of the time it was 78-79%. All my calculations show that I'm running between 210-230hp. Which is also the max for the injectors.

As per www.rceng.com worksheet.

stock:
43 psi fp, BSFC .5, IDC 82% = 174hp

Turbo:
*48 psi fp, BSFC .5, IDC 97% = 217hp
**54psi fp, BSFC .5, IDC 97% = 230hp

* 48 psi, because 43 psi + 5 psi boost = 48psi
** 54 psi, because I've heard that with the walbro fuel pump the stock fpr is a restriction and causes the pressure to rise to 54psi.

A 15% increase in Fuel over stock (82% to 97% IDC) = 200hp, but with the 11% increase in fuel pressure (43psi to 48psi) the hp number goes to 222hp. So from these calculations i'm estimating 210-230hp. Which is also the max for these injectors. Seem right?

-Chav

Your BSFC is off for turbo.
Its more like .6-.65 for turbo cars, so you're making considerably less power than you would think.

Originally posted by Chav
stock:
43 psi fp, BSFC .5, IDC 82% = 174hp

Turbo:
*48 psi fp, BSFC .5, IDC 97% = 217hp
**54psi fp, BSFC .5, IDC 97% = 230hp

* 48 psi, because 43 psi + 5 psi boost = 48psi
** 54 psi, because I've heard that with the walbro fuel pump the stock fpr is a restriction and causes the pressure to rise to 54psi.


-Chav

Midwayman, I tried the calculations for .6 BSFC, but they are incredibly low hp numbers.

48 psi fp, BSFC .6, IDC 97% = 181 hp
54 psi fp, BSFC .6, IDC 97% = 192 hp

I'm not running rich enough to use the .6 BSFC. I'm running close to the same ratio as I did stock according to the EGT and the narrow band o2. If these figures were right though, then it would indicate that the injectors couldn't even support 200hp turbo charged.

-Chav

Here's the math I'm coming up with using .55 as BSFC since a low-boost set-up falls almost between forced induction and NA (.55 is the low end of FI).

fomula for injector sizing:
flow rate=MaxHP x BSFC / #injectors x IDC
(flow rate in lbs/hr, multiply by 10.515 for cc equivalent)

Thus:
280=MaxHP x .55 / 4 x .85
MaxHP=~227bhp

That seems about right. It's hard to really determine what fuel consumption actually is in these cars. Anyone have a way to measure it? I suppose we could get good dyno results right from the crank and do the math to figure out BSFC from duty cycle, brake horsepower, and injector size. Anyone have a dyno run from a turbo 2.5 right from the crank with all the necessary numbers?

~Garrett

I just tried that formula again, but I get different numbers.

(227 x .55) / (4 x .85) = 36.72

36.72 x 10.5 = 385cc injectors

I think the problem is that in your calculations you didn't do the max hp x bsfc and 4 x .85 first and than divide.

http://www.rceng.com/formula-1.gif

with a .55 BSFC

48 psi fp, BSFC .55, 97% IDC = 198hp
54 psi fp, BSFC .55, 97% IDC = 210hp

-Chav

Why isn't this making sense though? I guarantee the Haltech is giving me the correct IDC values when it logs since it is the unit controlling the injectors. On top of that I am running 5psi max boost on stock injectors (which I'm quite sure are still 280cc). Haltech says even at high RPMs at full boost I'm only peaking maybe to 90% duty cycle.

Now consider the HP rating for a WRX. I think my car's weight is very close to that of a Rex, yet my car is considerably faster. It can't have that much to do with gearing could it? I assumed since they weigh about the same that I am putting more power to the wheels than a Rex so I'd be doing better than 227bhp. What isn't making sense?

~Garrett

Garrett, I can't help but feel like these equations don't take everything into consideration. You are with out a doubt making considerably more than the 280cc injectors at 90% IDC should be making according to those calculations. The only way to solve this is to, at the very least, put a car on a dyno and watch the power vs. IDC. The best thing to do is to put an engine on a dyno and watch the power vs. IDC.

-Chav