Tuning a Classic FAST

xp works fine , you can actually run on even lower versions like95/98
program doesnt need a lot to run but if i were looking for a laptop i would look for atleast win 7 so you can go online with some security. win 7 netbooks are really cheap on ebay
 
I got my laptop yesterday. Dell latitude Win 7. 100 bucks and it works great thus far. Think it needs a new battery but...oh well.
So I hooked it up and connected the laptop through the c-com cable. That is 'A LOT' of info to digest. I dont even know where to start on it. The car runs and drives as is but it has a hard start issue when its cold and it also ( idle is set to 1,200 rpms) hesitates from 1500 to 2000 rpms when the car is driving. While in park the car has zero revving problems. Would it be in the tune or perhaps the rev issue has something to do with the torque converter?
 
if you switched from a chip and it idled and started fine before the fast and provided you had your tps , fpressure and iac set up correctly, no vac leaks ..then the tune could need some work .
if you click on HELP/contents... at the top menu bar of c-com youll get the fast manual , look at initial setup and read it and follow the steps
i can tell you if you are on a stock balancer make sure the timing base is set at 10 under operation parameters , if you have a bhj they are usually off (sometimes alot) ,once the car will idle fix the base idle timing cells to say 30 degrees and check timing (with a dial back timing light ) and adjust the base timing parameter as needed to achieve correct timing
if this is a new setup youll need to set the iac or tps just as you would with a chip but you need to get the idle down to see the iac true reading
the idle can be lowered (view/idle functions/ idle vs clnt) and you may need to lower the throttle follower value if the tps is set higher than whats normal. check that the min tps is set correctly ,( view/ idle function/ min idle) and that value be atleast 1 above whatever dashboard is showing for tps at idle (usually 10-13)
the ve can be adjusted so theres less wander around the idle cells (view/ fuel table/base ve table) and so its not too rich
if you havent already done it make sure the IAT sensor is installed and connected after the intercooler either in uppipe or plenum/manifold
 
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So.... much info to digest! How does someone remember it all?
The car was tuned prior to my ownership with the fast and was setup for drag racing. The original 3.8 is no longer there. It has a 4.1 bored .060. So its a 256. It has a T-60 turbonetics with an old school ATR intercooler. That is what the dashboard stated on the fast programming anyways. The car will not be drag raced since it has t-tops. I can feel the car torque up when power braking and I would like to keep it in shape. I did save the program that is in the FAST ECU but I have no Idea how to post it for someone to look at. I could probably figure it out though. I know it doesnt have vacuum leaks I replaced all the vac hoses and zip tied them. I also replaced the plastic vacuum block on top of the throttle body. Fuel Pres is at 43lbs at idle. Fuel feed line was also replaced. Has a brand new Deautschwerks 340 pump with kirbans hotwire kit and adjustable FPR. It also has headman super comp headers on it. I installed on of earlbrown's boost controllers. Boy did that change how the car drove. INSTANT spool. After the hesitation the car wanted to fly! The fuel in the tank was lower than a 1/4 tank so that also could have been part of my hesitation issue.
One thing I did do was try to adjust the idle mechanically. Have since found out that the screw on the throttle body isnt used for that purpose. :( That is for idle air adjustment. I believe I fixed that. I set the TPS switch also to .38 volts with the throttle closed. I also checked it at full throttle and it went to 4.4 v. That was where is should be from what I read on vortex Buick.
 
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You need to do some data logging of the cold start then you can start adding fuel to the warm up enrichment table and afterstart tables. It just too lean and stubling when cold. If you click the link in my sig you can read up more on the system.
 
norbs said:
You need to do some data logging of the cold start then you can start adding fuel to the warm up enrichment table and afterstart tables. It just too lean and stubling when cold. If you click the link in my sig you can read up more on the system.
Click to expand...

I actually copied the stuff in your link before I got into the tuning portion of the cpu. The car was not running when I bought it. At start-up the AFR is at 14.3. Says the data that on the tuning program. Unfortunately the data logger didnt come with the car. Of course the programming I downloaded from FAST will help with that.
 
After reading your link again. It turns out 14.3 is too lean. It says right in the link that a 13.1 or richer AFR might be needed to keep away from the car dying from putting it in gear or burping the throttle on cold starts. If I enrich the AFR that should mean I can lower the idle speed from the 1,100 rpm it is set at.
 
I changed the initial AFR from 14.3 to 13.1 at initial start up and the car starts and runs right away. In the graph all I changed were the 14.3's to 13.1's. Would I have to change the progression of the others to balance it out? I did some testing and put it in gear and the same hesitation that I had before is still there. So I will have to do some more digging. I also lowered the Idle speed from 1250 to 980 rpms too. I believe they idled it that high because of the hesitation/falls on its face at 1500-2000 rpm issue. Idle quality didnt change at all so I hope I dont need to increase it back to what it was.
 
Im also trying to figure out IAC P Term and IAC PD term. Im thinking that since I lowered the idle RPM that I would likely need to mess with the IAC as well since that controls the air/fuel mixture at idle. I read the booklet but Im unsure of how to figure it out.
 
iac is set same as you do with a chip , adjust the throttle blade screw and watch the iac target at operating temp
 
What would the target be? It has been fluctuating between 0 and -2.

I did some tuning and now the engine doesnt want to run with the original tune unless I change the initial blocks of tuning from the 14.3 to the 13.1. I also changed the spark plugs because I thought I may have fouled the UR5's (gap at 32) to ACr42ts (gap at 30). Would that have anything to do with it?
 
iac target should be 20-30 just like a chip at idle at op temp , if your IAC target is showing lower you need to turn the throttle blade screw to close the throttle blade, if its 0 and wont budge you probably have a vac leak
also make sure in the throttle follower table (under idle parameters) allows the iac to get to below 20 at the tps base position

my idle is at 13.1
my plugs are ac r42s at .024 so yours shouldnt be an issue at .030
 
If I have a vacuum leak Ill have to take the intake off and change the intake gasket. I have changed all the other vacuum sources that I could find. on top of the engine. I am seeing a bit of pooling oil on the valley area of the lower intake. I was a bit worried about that.
Might as well replace that before I try to tune any further. One leak like that changes everything in the combustion cycle.
 
i use the felpro 96033 and the rubber rail seals or a bead of right stuff rtv
cometic makes nice single gaskets but you need to install a valley pan to run a stock pcv setup
on my ttop i have the cometics and an aluminum valley pan from american machine
for taller ported heads (like the TA SE race ported you would need to run custom individual gaskets like TA perf sells and a seperate valley pan
 
How much of my closed loop AFR should be in the 13.1 range? Up to 100 Map (kPa)? I have it 13.1 from 0-1600 rpms up to 58 Map (kPa)

Im still trying to figure out how to get that file transferred so it can be looked at. I really dont want to sit here and block it all out and use forum bandwidth on it.
 
Here are some numbers I wrote down from the c-com program with the car Idling. Car still dies when cold on initial start-up. Second time it stays running.
A/F stays at 13.1 at idle (1,100 rpms)
TPS-5
Map kPa reads around 37-40
IAC target reads from 84-93 no matter where the idle air screw is set. Vacuum leak? Set wrong??
IAC PD Term -1-0
I read in Norbs link that the air temp probe needs to be in the intake tubing after the intercooler. That I havent done yet.
The other troubling thing is that Im not seeing any readings of the 'Actual" A/F ratios in the programming. I know what the computer is sending to the engine and its saying what it is but on the programming screens the "Actual A/F" ratio number is listed as 0.0 at all times. Shouldnt that be reading something?
 
pacecarta said:
iac target should be 20-30 just like a chip at idle at op temp , if your IAC target is showing lower you need to turn the throttle blade screw to close the throttle blade, if its 0 and wont budge you probably have a vac leak
also make sure in the throttle follower table (under idle parameters) allows the iac to get to below 20 at the tps base position

my idle is at 13.1
my plugs are ac r42s at .024 so yours shouldnt be an issue at .030
Click to expand...
Throttle follower has the minimum set at 24 at the (0 tps position) with a max of 66 at the 44 position for the TPS.

On the Start IAC Pos. vs Coolant Temp. page
The IAC opening starts at 224. It runs there until the temp reaches 61 degrees then declines until it reaches a position of 143 at a temp. of 140. At a 181 temp the number for the IAC position is 131.

This stuff is all greek to me. 4 corner idle carbs are mostly what I have worked with.
 
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