robof16
November 13th, 2011, 02:17 PM
So I set B2331 and B2232 all up to 150mm3 (hopefully that’s high enough), built TVPOS table in Scan Tool and proceed to do some logging.
Bottom line: It’s following the stock vane table within 1% point everywhere in the table! It’s the same on my near stock and race tune.
I was certain that the bigger turbo would need more closed (bigger #) vane positions to generate the same boost.
Contrast: With everything stock in 2331 and 2332, I had a LLY vane table loaded and the log showed vane target positions even greater than the LLY vane table. In many cases this was up to 30% more than a stock LMM vane table. Example: 86% vs 54% for the stock vane table. That seems like a lot to me.
Observation: At steady state cruise the lower vane positions commanded in the first example resulted in 0-2 psi of boost vs about 5 psi for the LLY tables (as expected I guess) but, the low boost (vane) settings felt just as responsive (maybe more) and would probably yield more MPG (less than ½ of the drive pressure too). I can’t say for sure but I think I liked the way the truck performed a little more with 2331/2 disabled.
Update: Vane target position still following whatever is in the vane table with 2331 and 2332 set to 190. Apparently it's not ignoring the vane tables as expected. I get a lot more drive pressure and only slightly better spool with the LLY table vs the LMM.
Bottom line: It’s following the stock vane table within 1% point everywhere in the table! It’s the same on my near stock and race tune.
I was certain that the bigger turbo would need more closed (bigger #) vane positions to generate the same boost.
Contrast: With everything stock in 2331 and 2332, I had a LLY vane table loaded and the log showed vane target positions even greater than the LLY vane table. In many cases this was up to 30% more than a stock LMM vane table. Example: 86% vs 54% for the stock vane table. That seems like a lot to me.
Observation: At steady state cruise the lower vane positions commanded in the first example resulted in 0-2 psi of boost vs about 5 psi for the LLY tables (as expected I guess) but, the low boost (vane) settings felt just as responsive (maybe more) and would probably yield more MPG (less than ½ of the drive pressure too). I can’t say for sure but I think I liked the way the truck performed a little more with 2331/2 disabled.
Update: Vane target position still following whatever is in the vane table with 2331 and 2332 set to 190. Apparently it's not ignoring the vane tables as expected. I get a lot more drive pressure and only slightly better spool with the LLY table vs the LMM.