12200411 - A Few General Questions

Thanks David- Yes, it appears my table is correct per your 'Returnless' screen shot.

Quote:

---

Originally Posted by ScottP

I ran into the same issue when I retrofit a 12200411 PCM to my 455 Pontiac. The problem was that the VE table I started with was far too low for my application. The 411 uses a VE table whose entries are proportional to engine displacement, so if your engine is much larger in displacement than the stock calibration you started with, you will need to scale the VE table accordingly, just to get in the ballpark. In my case, the finished VE table for my 455 was nearly 2x that of the L31 calibration I started with in the idle/low load areas that you'd be using when transitioning from startup fueling to the VE table. This meant that before I made the correction, as the PCM transitioned from cranking fueling to run fueling, it would be VERY lean and would stall. -Scott

---

I have not touched the VE tables and am currently using the stock LS1 Corvette table- How do you know where and how much to adjust? Is it more trial and error or is there a methodology? Thanks! Elm

To start with, you could scale the VE table by the ratio of your engine's displacement (409ci) to the stockLS1 (346ci) whose VE table you used, so in this case, x1.182.Once its running, you'll need to datalog your trims to begin fine tuning the VE table. Both EFILive andHPTuners have excellent logging utilities that bin your trims into the same cell structure as the VE table.

Quote:

---

Originally Posted by ScottP

To start with, you could scale the VE table by the ratio of your engine's displacement (409ci) to the stockLS1 (346ci) whose VE table you used, so in this case, x1.182.Once its running, you'll need to datalog your trims to begin fine tuning the VE table. Both EFILive andHPTuners have excellent logging utilities that bin your trims into the same cell structure as the VE table.

---

Do I want to modify just the 'Main VE' table or also the 'VE While Cranking' table (EFILive)? Thanks! Elm

So how did this thing come together?

Quote:

---

Originally Posted by dfarr67

So how did this thing come together?

---

It's slowly coming together.
I was on a roll until I was diagnosed with cancer so unfortunately everything else in life has taken a back seat.

I did get the car running and got the idle dialed in pretty well but had to put the project on hold before I could get out and get the 'driving' tables dialed in. I am still hoping to get it wrapped up before Winter- I REALLY need to get this thing on the road, it's been too long.

The advice I've received so far has helped quite a bit in getting the tune closer to where it needs to be. I've only taken the car around the block but I can already tell is has a ton of power so I'm excited to get it finished.
More to come- Hopefully!
Elm

Yes the big C- was rushed for tests last year, the cancer hospital has got to be the most depressing place I've ever been- best wishes. As for the project- my conversion parts are almost together, but time flies.

Quote:

---

Originally Posted by dfarr67

Yes the big C- was rushed for tests last year, the cancer hospital has got to be the most depressing place I've ever been- best wishes. As for the project- my conversion parts are almost together, but time flies.

---

Thank you-
I'm actually temporarily living in Houston for this round of treatments but hope to be back home in October to finish the Vette.
What is your conversion?

Finishing up my air cleaner set-up..
Attachment 13204

Man, nothing like a big smack to the back of the head. I wish you both the best.
-Carl

Mine turned out to be negative, still it gives you pause for thought about the bullet dodged.