411 Swap 383 Vortec Newbie To Tuning. Where To Start?

[supspt454]

I have done a lot of searching and reading before posting. It seems all situations are different obviously. Did the 411 swap on my 383, so now my truck has the brains of a 02 Chevy Express Van. VATS disabled, some minor things already flashed when I got it. EGR turned off, bank 1 sensor 2 and 3 turned off, alt codes turned off. I corrected the cyl volume to 0.78451. EGR is still on the engine for now, pink wire on the connector is ran to the 411 as per Lextech spread sheet. Truck runs and drives excellent. Way smoother than the old black box. No misfires. Only issue is when you start it. It fires right up, then starts to stumble for a few seconds. Sometimes shutting off and having to re start. If I give it some throttle and let it run for about 8 seconds at 1000 rpm, then let off it will idle all day around 600. I did raise the idle on the tune to that from 550. Trans seems to shift fairly early. 1-2 will shift very soon, and the 2-3 shift is kind of soft, not firm like it used to be. So with all that being said, where do I start? I am reading and trying to understand the tuning lingo. Just clueless on where to start. Any help is greatly appreciated. Vehicle specs are in my sig. Thanks all!

SJ

 

[RDF1]

Post your tune and a datalog.

 

[supspt454]

Post your tune and a datalog.

Hi. Yes I will. How long of a drive should I do? Sorry, like I said, new to EFI tuning. I have to make a quick run to the store, be about a 5-10 min drive.

 

[RDF1]

Just of the starting issue.
Can go ahead ans post your tune tho

 

[supspt454]

Just of the starting issue.
Can go ahead ans post your tune tho

I know this is dumb, but I am searching on how to convert the .hpt files so I can share it on this forum.

 

[L31MaxExpress]

1st you need to copy the VE table from an untouched L31 file, then paste it back in after changing the displacement. The VE table will be reduced by the same percentage you increase the cylinder volume.

From there, you need to setup the Base Running Airflow. I setup a histogram to do this.

Once the BRAF is setup correctly, you may need to adjust the other startup airflow values.

 

[99xcss4]

if you look on the reply section to post you will see at

You must be registered for see images attach

tach file(s) click that and find the file on your computer and click the open and it should work

 

[supspt454]

if you look on the reply section to post you will see at

You must be registered for see images attach

tach file(s) click that and find the file on your computer and click the open and it should work

Already tried that first. This forum will not support the .hpt file. I was trying to find a way to convert it.

 

[supspt454]

1st you need to copy the VE table from an untouched L31 file, then paste it back in after changing the displacement. The VE table will be reduced by the same percentage you increase the cylinder volume.

From there, you need to setup the Base Running Airflow. I setup a histogram to do this.

Once the BRAF is setup correctly, you may need to adjust the other startup airflow values.

Are you talking about Primary VE ECM 12350

 

[supspt454]

1st you need to copy the VE table from an untouched L31 file, then paste it back in after changing the displacement. The VE table will be reduced by the same percentage you increase the cylinder volume.

From there, you need to setup the Base Running Airflow. I setup a histogram to do this.

Once the BRAF is setup correctly, you may need to adjust the other startup airflow values.

I made some changed and did the following one change at a time.
Pasted an untouched L31 VE Table, truck did not run very good this way.
So I put it back to the way it was when I changed the cyl volume to 383, when the program changes it for you. Truck ran good again.
Basically in small increments, doubled the BRAF to get the truck to start without throttle input. RPM was hanging a little.
Backed some idle spark advance off from 400 to 1200 rpm. Truck seems to like it so far.

There is still so much that needs messed with, but it is now running better than ever. Still trying to learn.