What steps do you guys use to tune lower RPM stuff to make the car more driveable
09-26-2002, 12:32 AM
#1
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Join Date: Nov 1999
Location: Columbus, Ohio
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What steps do you guys use to tune lower RPM stuff to make the car more driveable
Well, I finally got the car to a point where I can finally do my tuning.
I was playing with an Ed Wright program a friend of mine had for a combo similar to mine....let's just say the car was not happy with that.
I downloaded a heads/CC306 program off of Brent's site. The car seems to run pretty decently on that. I'm taking her to the dyno Saturday and tuning on the wideband. That is fine and dandy for the adjusting for WOT (car pulls fine to 7000 RPM on the current power enrichment tables, though is quite rich). So for the dyno, I'll just see how rich and subtract fuel where needed.
But closed loop tuning, and for that matter, open loop tuning is where I need help. The car doesn't have much cam surge, so I know I'm not too far off (it surged pretty badly on stock programming). From idle to around 2000 RPM or so, the car just runs a little rough. It will cruise alright on the highway in 6th gear, but in general the car just isn't real smooth in this area.
Also, when starting the car, I HAVE to rev the motor to get the idle to settle. Otherwise, it will stick at 500RPM and barely run for a while, and EVENTUALLY go back to idling normal. Not sure what kind of programming I can do for that; perhaps the cranking advance tables (I'm using LT1_Edit by the way).
I guess what I'm looking for is how do you guys go about dialing the car in for the street? I'm assuming do work in the Open Loop Temp vs. Load tables and more importantly, the 400-2000 RPM Vol. Efficency tables.
Basically, how do I go about adjusting those tables to make the car driveable? What steps do you usually take to do it? I'm looking for general guidelines, I'm sure it is kind of a guess and check type thing. I'm just trying to see how I can get this thing tuned in nicely. Maybe a webpage guidelining this. I already know how to USE LT1_Edit pretty well, and understand what most of the table are for, but it is the getting to the right values on some of these tables that gets frustrating.
I was playing with an Ed Wright program a friend of mine had for a combo similar to mine....let's just say the car was not happy with that.
I downloaded a heads/CC306 program off of Brent's site. The car seems to run pretty decently on that. I'm taking her to the dyno Saturday and tuning on the wideband. That is fine and dandy for the adjusting for WOT (car pulls fine to 7000 RPM on the current power enrichment tables, though is quite rich). So for the dyno, I'll just see how rich and subtract fuel where needed.
But closed loop tuning, and for that matter, open loop tuning is where I need help. The car doesn't have much cam surge, so I know I'm not too far off (it surged pretty badly on stock programming). From idle to around 2000 RPM or so, the car just runs a little rough. It will cruise alright on the highway in 6th gear, but in general the car just isn't real smooth in this area.
Also, when starting the car, I HAVE to rev the motor to get the idle to settle. Otherwise, it will stick at 500RPM and barely run for a while, and EVENTUALLY go back to idling normal. Not sure what kind of programming I can do for that; perhaps the cranking advance tables (I'm using LT1_Edit by the way).
I guess what I'm looking for is how do you guys go about dialing the car in for the street? I'm assuming do work in the Open Loop Temp vs. Load tables and more importantly, the 400-2000 RPM Vol. Efficency tables.
Basically, how do I go about adjusting those tables to make the car driveable? What steps do you usually take to do it? I'm looking for general guidelines, I'm sure it is kind of a guess and check type thing. I'm just trying to see how I can get this thing tuned in nicely. Maybe a webpage guidelining this. I already know how to USE LT1_Edit pretty well, and understand what most of the table are for, but it is the getting to the right values on some of these tables that gets frustrating.
09-26-2002, 03:07 PM
#2
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Join Date: Dec 1969
Location: Calgary, Alberta, Canada
Posts: 324
You might want to raise the idle speed by 100 rpm or so. That will help.
You may also want to remove some timing at the idle associated rpms, that may help a bit, it won't help the emmisions, but may smooth things out a bit.
These cars are normally MAF enabled, so changing the VE tables does little if anything at all to the mixture. The computer is going to the O2s and trying to keep them happy.
Hope this helps
LWM
You may also want to remove some timing at the idle associated rpms, that may help a bit, it won't help the emmisions, but may smooth things out a bit.
These cars are normally MAF enabled, so changing the VE tables does little if anything at all to the mixture. The computer is going to the O2s and trying to keep them happy.
Hope this helps
LWM
09-26-2002, 03:10 PM
#3
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Join Date: Nov 1999
Location: Columbus, Ohio
Posts: 645
Hmmm, maybe I'll just start yanking a couple degrees of timing all over the lower RPM's and see what happens.
BTW, emissions are NOT a concern. The only emission related item still left on the car is the charcol canister system. No AIR, EGR, or Cat.
BTW, emissions are NOT a concern. The only emission related item still left on the car is the charcol canister system. No AIR, EGR, or Cat.
09-26-2002, 03:24 PM
#4
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Join Date: Aug 2001
Location: Carlisle, PA
Posts: 874
Did you try VEMaster to see if that helps at all.
Check out this link.
http://www.akmcables.com/vemaster.htm
It can be downloaded there as well.
I made a copy of my bin file before I ran it through VEMaster because VEMaster changes the table values .
I don't know if that helps but I thought I throw it in the ring.
Check out this link.
http://www.akmcables.com/vemaster.htm
It can be downloaded there as well.
I made a copy of my bin file before I ran it through VEMaster because VEMaster changes the table values .
I don't know if that helps but I thought I throw it in the ring.
09-26-2002, 06:03 PM
#5
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Join Date: Sep 1999
Location: Kissimmee/Orlando, FL
Posts: 670
I'm no expert but all you can really do is play with the timing tables to try to smooth things out.
One of the evils with closed loop running is that it will always try to maintain 14.7:1 no matter what you do. You can play with the VE and MAF tables all day and the PCM will just adjust the BLM's till its back at 14.7:1. It doesnt care if the car would run better if it were richer or leaner, it wants stoich and it will do what it takes to get it.
Thats why closed loop = evil IMO
One of the evils with closed loop running is that it will always try to maintain 14.7:1 no matter what you do. You can play with the VE and MAF tables all day and the PCM will just adjust the BLM's till its back at 14.7:1. It doesnt care if the car would run better if it were richer or leaner, it wants stoich and it will do what it takes to get it.
Thats why closed loop = evil IMO
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