Need help tuning cammed 5.3
#1
Need help tuning cammed 5.3
First off im using HPT, and this is my first vehicle ive tuned with a cam. Cam is a 224/224 581/581 on a 112. Ive read and read and i understand some of it but i still need ALOT of help. It idled fine for about 10 min. then started running horrible. My LTFT's and STFT's went crazy. Im also throwing a P0300 misfire code. I have 5 min. of scanning but i dont know how to post it. If someone could tell me how to post it that would be awesome and we could go from there. Thanks, Eric.
#3
The missfires are probably from the springs/cam, i have always lowered those test values or zeroed them out... Do you have a wideband? Also have you tried dialing in the VE, MAF and Desired Airflow table or are they stock?
#4
The cam is less efficient than the stock one at lower rpms, thats why the trims are crazy. You are likely going to have to decrease the values in the ve and maybe the maf too to get the lower rpms leaned out some. I'd say below 2600 rpms or so. A little more spark may help at idle as well. Zero out the misfire tables, even changes in an aftermarket torque converter can make it throw the p0300, hell, you'll know when its really misfiring imo..lol.
Idle airflow is where alot of people overdo it. I would either crack the throttle blade a bit more (or drill the hole out....i rarely do this). Then you can use the desired airflow and startup airflow tables to fine tune it. Too much on these tables as well as the throttle cracker and you'll be hunting some serious bucknasty surging. I usually end up lowering the throttle cracker airlow table too, because once you've manually introduced more airflow, the added flow from this table will cause a cruise control effect. SO will too much air in the desired airflow table. That cam should idle at 850 or so pretty comfy.
If it is dbw, there is alot less to mess with, the base table will get you where you need to be in most cases.
Idle airflow is where alot of people overdo it. I would either crack the throttle blade a bit more (or drill the hole out....i rarely do this). Then you can use the desired airflow and startup airflow tables to fine tune it. Too much on these tables as well as the throttle cracker and you'll be hunting some serious bucknasty surging. I usually end up lowering the throttle cracker airlow table too, because once you've manually introduced more airflow, the added flow from this table will cause a cruise control effect. SO will too much air in the desired airflow table. That cam should idle at 850 or so pretty comfy.
If it is dbw, there is alot less to mess with, the base table will get you where you need to be in most cases.
#5
Its a cable TB. Also i posted over at HPT forum, but just tryin to get as much info as possible.
Here's what ive done so far: Added 2 g/sec to idle airflow across the board both in P/N and in gear, added 4º of idle timing 1200 rpm and under and 0.08 – 0.28 g/cyl inclusive.
Multiplied the Main Ve Table column 400rpm by 60%, column 800rpm by 80% and column 1200rpm by 90%. Smoothed 1200rpm through 2000rpm columns.
Added 2 g/sec to the Start-up Airflow Initial table across the board.
Added 50 camshaft rotations to the Idle Start-up Airflow Delay vs. ECT, deleted rear O2's and evap.
Here's what ive done so far: Added 2 g/sec to idle airflow across the board both in P/N and in gear, added 4º of idle timing 1200 rpm and under and 0.08 – 0.28 g/cyl inclusive.
Multiplied the Main Ve Table column 400rpm by 60%, column 800rpm by 80% and column 1200rpm by 90%. Smoothed 1200rpm through 2000rpm columns.
Added 2 g/sec to the Start-up Airflow Initial table across the board.
Added 50 camshaft rotations to the Idle Start-up Airflow Delay vs. ECT, deleted rear O2's and evap.
#6
Do you mean you reduced or increased the values in the ve? 2g/sec might be ok on the startup table but you can adjust the set screw on the tb to try and keep the desired airflow table lower. What are your values in that table above 150 ect??
#7
Also keep in mind that too much timing can cause a high idle condition and you will get some funky **** going on when the pcm trys to pull air and timing to get the idle back to the desired rpm. I wouldn't add any more timing than you already did, in most cases on a cam that mild, airflow and fuel will line it out on its own.
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