FAST Tuners, I need some tech help

[supremeefi]

Originally Posted by camcojb

The main thing is you don't want the IAC to be opened a bunch just to get the car to idle at temp with no load. Then you don't have anything left for load situations like the a/c turning on, or higher cold idle, etc. First, get the engine fully warmed. Shut off any idle timing compensation (timing trim) and set the idle speed to something well below your desired speed and what it will even idle at, like say 400 rpm. Also make sure all the timing tables around the idle speed are the same, so it's not bouncing back and forth between tables with different timing amounts.

Fire it up and set the throttle blade opening so the engine is at your normal idle speed, say 900 rpm or whatever it will be idling at normally. That way, the throttle body will have the right amount of air bypass to idle the engine without the IAC getting involved when it's warm. You'll then have full use of the IAC when you need it; cold start, a/c or other load kicks in, etc. Reset your TPS settings for idle, turn the timing trim back on, and re-adjust any timing tables you may have changed and you should be good to go.

Wow, and the Accel gets a bad wrap for being "hard to tune". At least on that you simply do "Forced Timing" so it holds it at any rpm etc. Then shoot for IAC counts of 8-10 at idle hot with no load. A lot of the rest of the IAC stuff takes care of itself from there, geez.

Anyway, I agree with Jody on most everything but a couple things to remember. I like a little IAC at idle when hot, sometimes it will decel a little better. With a cam that size the IAC isn't really stabilizing the idle anyway, your spark control is taking care of most of that.
Also your starting fuel will bleed over into your initial running fueling, keep that in mind.
And if possible, turn the key on, let the O2 heat up and then try to fire it while checking your air/fuels. Yes your fuel pump will cycle but it will restart the second it sees an ignition signal. That may help in directing as to which way to go. I agree, 42ms seems excessive.

[camcojb]

Originally Posted by supremeefi

Wow, and the Accel gets a bad wrap for being "hard to tune". At least on that you simply do "Forced Timing" so it holds it at any rpm etc. Then shoot for IAC counts of 8-10 at idle hot with no load. A lot of the rest of the IAC stuff takes care of itself from there, geez.

Anyway, I agree with Jody on most everything but a couple things to remember. I like a little IAC at idle when hot, sometimes it will decel a little better. With a cam that size the IAC isn't really stabilizing the idle anyway, your spark control is taking care of most of that.
Also your starting fuel will bleed over into your intitial running fueling, keep that in mind.
And if possible, turn the key on, let the O2 heat up and then try to fire it while checkng your air/fuels. Yes your fuel pump will cycle but it will restart the second it sees an ignition signal. That may help in directing as to which way to go. I agree, 42ms seems excessive.

the way I described has always ended up with some IAC at idle for me. I agree, you want a bit, just not half or more of your adjustment range being used up just to get it to idle when warmed up. And Accel was harder to tune for me than any other system I've tried (Gen VII anyway). Does not make it bad or not capable.

[supremeefi]

Originally Posted by camcojb

the way I described has always ended up with some IAC at idle for me. I agree, you want a bit, just not half or more of your adjustment range being used up just to get it to idle when warmed up. And Accel was harder to tune for me than any other system I've tried (Gen VII anyway). Does not make it bad or not capable.

Yes I know I hear that sometimes. But I gotta tell you, now that I've done both the XFI is cumbersome to me. There are whole lot more viable shortcuts on the Accel than the XFI. And I still think the software on the Accel is head and shoulders above the XFI, especially on the 3D graphs.

With the Accel, I've just always adjusted the throttle blades so that I get an IAC count of about 8-10 out of a possible 100 hot in neutral, done.
Having to turn this and that off, changing your spark table, that's a hassle. That's just one reason why I'm so amazed that the Accel has gotten such a bad wrap from time to time.

Oh well it is what it is I guess. Best of luck 67ragtp.

[camcojb]

Originally Posted by supremeefi

Yes I know I hear that sometimes. But I gotta tell you, now that I've done both the XFI is cumbersome to me. There are whole lot more viable shortcuts on the Accel than the XFI. And I still think the software on the Accel is head and shoulders above the XFI, especially on the 3D graphs.

With the Accel, I've just always adjusted the throttle blades so that I get an IAC count of about 8-10 out of a possible 100 hot in neutral, done.
Having to turn this and that off, changing your spark table, that's a hassle. That's just one reason why I'm so amazed that the Accel has gotten such a bad wrap from time to time.

Oh well it is what it is I guess. Best of luck 67ragtp.

I think it's what you learn on. My start was with a prom burner, but the program didn't give much to change. My first real EFI tuning was with the old FAST unit, which I still like. Nowhere near the capabilities of the new stuff, but a solid performer that was easy to tune.

We've spoken about Accel in the past. I think the reason the Gen VII got such a bad rap was that when it came out they made anyone with a pulse an EMIC. You ended up with a lot of untrained tuners out there, that could not tune the system. That made the system look like the problem, when it actually was the other way around.

[supremeefi]

Originally Posted by camcojb

I think it's what you learn on. My start was with a prom burner, but the program didn't give much to change. My first real EFI tuning was with the old FAST unit, which I still like. Nowhere near the capabilities of the new stuff, but a solid performer that was easy to tune.

We've spoken about Accel in the past. I think the reason the Gen VII got such a bad rap was that when it came out they made anyone with a pulse an EMIC. You ended up with a lot of untrained tuners out there, that could not tune the system. That made the system look like the problem, when it actually was the other way around.

Well put Jody, I couldn't agree more.

[GregWeld]

Something I always found helpful when trying to find an issue -- turning off the 02.... so it wasn't chasing the A/F ratio all over... Then I'd watch the A/F to see if it was at the number I'd set "on it's own". Ditto timing... set a non corrected # - and check that with the timing light... and make sure they match etc.