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View Full Version : It drives!! I started tuning...need advice...



EvilSpeeder
02-03-2005, 03:12 AM
I finally drove my car tonight!! It's still not 100% together, the bumper still needs to be put back on, and I have to hardwire some stuff in thats just stuck together right now.

I left the 440s in it to see if I could tune it that way. It idles nicely at about 12.5:1. I've got the regulator turned all the way down and the afc leaned out a bunch, so I think it's safe to say that I have too much injector. AFR jumps around a little but it's 12.5: or richr everywhere and never gets richer than 10 or 10.5. I need to hook up the rpm and throttle inputs to the logger before I try to tune any more. Right now I'm just running off the wastegate. It's supposed to be an 8lb spring, but I'm only seeing about 7 showing on the gauge. I'm not sure how much more boost the clutch is going to take. It's not slipping right now, but it feels a little iffy. I'm not sure where the timing is at becuase I haven't gotten my timing light in the mail yet, but I retarded it about 10deg from where it was, so that should put me around 7deg advance (I ran a lot of timing, I know, that motor loved it).

I'm not sure what route I should take with the turning. I really didn't intend to do any huge adjustments with the AFC, I really wanted to use it only to smooth out the curve. With the huge injectors in there, I've got the regulator leaned out, the regulator gain turned all the way down (so its running on the stock regulator only), and the AFC a full 50% lean on the low throttle and varying from 40% lean to 20% lean at high throttle (gets richer with higher rpm, should probably add some regulator gain).

What I'm thinking is that I should switch back to stock injectors and jack the fuel pressure up so that I'm not making drastic adjustments with the AFC. This should also solve some of the part throttle driveability issues I'm experiencing, although they're mostly due to the fact that my similated narrowband output isn't hooked up to the ecu yet, so it's in open loop all the time.

Anyway, what do you guys think? Keep the 440s, ditch them for the ~200cc stock injetors, or shell out some more cash for something in between? I suppose I could do the math and acutally figure it out if I wanted to, but that sounds like work!

Cliff notes: Car is fast, makes wooshy noises.

Snafu
02-03-2005, 03:53 AM
Haha, love the cliff notes.

So, if I'm getting this straight, you can't turn down fuel pressure with your FPR? If you could, I would do that, then add fuel using the afc.

You also have to think about the cycle duty your stock injectors would be going through.

If I were you, I would invest in an Aeromotive FPR so you can turn down your fuel pressure, then raise it on the 440's with the AFC. If not, snag some lime tops or brown tops and call it a day.

EvilSpeeder
02-03-2005, 04:13 AM
Yah, I really need to do the calcs to figure out where I'm at. The regulator I'm running is a rising rate regulator. It can't go lower than the stock regulator as it doesn't replace the stock regulator. I don't really think turning down the fuel pressure will solve much, it's definitely possible that I would have to turn it down *too* much and would start getting bad idle because of poor atomization. But at the same time, like you said, I need to make sure if I switch to the stock injectors that I'm not running them much past 85-90% duty cycle.

nuclearhappines
02-03-2005, 04:22 AM
the 8# spring for the wastegate is never daed on ... usually an 8lb spring means wastegate starts to open at 8psi... which means full open at 9,10,11 psi.. then you take out a few psi of pressure drop (intercooler) and you get what you get... don't worry too much about what the exact number is as long as you're not running into spikes or creep.

Injectors. You could do a few things... check with someone that has a normal 7afe and see what their total timing is ... then check your total timing and see how different it is and pull that much timing out ?

Or Do what snafu said. I'm with him on that. The setup you're using (more fuel capacity, less duty cycle) is typically a good N/A setup because you're adding timing ...

good luck with it

-nuke

ChrisD
02-04-2005, 03:38 PM
The stock ~200's would be way too small imho...

Personally I'd keep those injectors, get a good 1:1 FPR to replace the stock one, lower the fuel pressure a few psi, and do the tuning that way. You should be able to get decent atomization at as low as 30-35psi. That should buy you enough room to only need to make small adjustments with the SAFC. But the smaller the adjustments, the higher injector duty cycle you will run. Even the 3SGTE ECU allows up to 100% duty believe it or not. Whether or not that causes ignition advance, depends on the ecu and how it is wired (I'm not familar with your ecu too much).

Luni
02-04-2005, 04:06 PM
Yeah Id definately do what the others said.. Drop base fuel pressure and ADD fuel with your SAFC so you arent advancing your timing inadvertently.

EvilSpeeder
02-04-2005, 05:22 PM
Ok, I've been tuning on the 440s for two days now. I've got a decent AFR everywhere and the car runs great except for a small missfire that i still need to chase down. Heres the weird thing tho. I had a fuel pressure gage on it when I first started tuning but it was just a generic pressure gage. It never read much higher than 20psi. I thought, no way that can be right, the gage must be hosed. So I bought a new autometer gage. I put it in and it reads the same. Never over 20psi and the pressure drops when you blip it from an idle. If this is accurate, I don't see how the car can even be running right. Furthermore, I don't see how fuel pressure this low could even exist....the stock regulator is still there, still hooked up, still operational. I should not be able to lower the fuel pressure below the stock value. Stock on the 7a is listed as 38-44 IIRC in the BGB. How can this be??

Hooligan
02-04-2005, 06:38 PM
Is the gauge before or after the stock regulator?

Sean
02-04-2005, 07:09 PM
Is the stock FPR a rising rate regulator?

Your typical FPR will raise fuel pressure in a one to one correspondance with boost pressure. 1psi of boost, is going to net you an additional PSI of fuel pressure.

EvilSpeeder
02-04-2005, 09:06 PM
Is the gauge before or after the stock regulator?
:lolhittin
I can't believe how much of an idiot I am. Please disregard my previous post. I can tell I've been working on this thing for too long when I start doing shit like that.

Hooligan
02-05-2005, 06:12 PM
:lolhittin
I can't believe how much of an idiot I am. Please disregard my previous post. I can tell I've been working on this thing for too long when I start doing shit like that.

:)

At least it was an easy fix!

nuclearhappines
02-05-2005, 06:58 PM
On my next car, i'd like to do something like this. Except i want to do it on the bolt that where the fuel feed meets the rail so you have the gauge sticking off the end of the rail instead of off the end of the filter

http://www.clubcivicquebec.com/site/technical/Performance/005.html

quick google yields this:

http://www.automotosports.com/diy_misc.asp

http://www.automotosports.com/Productimages/fftap_thumb.gif

EvilSpeeder
02-05-2005, 07:48 PM
On my next car, i'd like to do something like this. Except i want to do it on the bolt that where the fuel feed meets the rail so you have the gauge sticking off the end of the rail instead of off the end of the filter

http://www.clubcivicquebec.com/site/technical/Performance/005.html

quick google yields this:

http://www.automotosports.com/diy_misc.asp

http://www.automotosports.com/Productimages/fftap_thumb.gif

I need one of those, but of course, it's the one thing on the page that doesn't link correctly to the shopping cart. WTF,

nuclearhappines
02-05-2005, 08:11 PM
when you buy a b&m FP guage it already comes with that fitting.

call b&m and just get the bolt alone maybe ?