I was dyno-tuning on the same dynapack which I used previously and noticed a drop of load values in my datalog.

Car is running 28psi tapering to 25psi, I was hitting 280-300 load values before but now my load values doesn't go pass 260 while running at the same boost.

The dyno settings are confirmed to be identical, and because of the loss in load, I'm making less power as well.

We checked and ensure there is no boost leak or fuel issue, spark plugs are fresh. There is no mis-fire or exhaust leak either. TPS is at 95% confirming TCU did not kick-in.

What else can you guys think of?

 

MIVEC settings can change you'rere load, were they modified in your most revised tune? Did you check cylinder compression?

 

MIVEC was not touched, compression is there.

 

Temperature maybe? On a stock car (tuned), my peak load is about 20-30 points less in the summer than the winter.

 

That's what I'm suspecting.

Normally at 28psi during cool days, I would be hitting 280 to 290 load cells.
But today at 28psi, I was only hitting 250 load cells.

Anyone else confirm the same experience?

 

not surprised, the weather conditions heat, RH,Baro does plays a big role.

same type of fuel ?

what are the power/tq diffs ?

just outta curiosity, why are you on dyno if nothing has changed or added/taken out ?

 

I put in a new BOV and needs a re-tune.

Same 94 oct fuel, same boost curve, same timing, fuel spot on at 11.0-11.1.

I was losing around 15% of power and torque, roughly the same percentage loss in the load I was hitting.

 

weather is most likely the culprit be nice to mother nature LoL stop polluting hahaha u need a HUGE CAT LVSBB6 j/k .

 

Why do you have it tuned so rich still post tune? 11 flat is very conservative IMO especially with 94 octane. Have you disabled your LTFT? Those could also be playing a factor if the car goes leaner/richer at times varying on your LTFT which would in turn probably reduce or increase your load.

 

I agree, change in temps/humidity.

Slightly off topic but shouldn't you be hitting more than 280 load on cooler days?

I ask because my stock turbo hits 280 load at 28psi if my temps are around 50ºF, I would've thought a Green could hit 320 at least.

 

Weather. Also, if your old BOV was a boost leak then that would make the load appear higher.

 

This morning`s temperature reduced by about 8 degrees so I datalogged a few back to back pulls, I`m happy to report that my load values has increased back to 280-290 range. Although I still find it`s a little under 1 to 10 ratio after a few hot pulls at 16 degrees celcius.

Looks like it is infact the temperature /humidity that were affecting my dyno pulls yesterday indeed.

 

It is possible that your wgdc is limiting your boost rather than load limiting your boost, causing you to have lower load values when the air is less dense. If you are logging boost error correction, and you see that it is maxed at 10, then your wgdc is your limit, rather than load. If you have a value less than 10, you are hitting target loads. (unless you changed your maximum upward wgdc correction)

 

I don`t recall seeing boost error correction during the runs. But in my case where the actual boost is already in-line with the the tune, I suspect that error correction won`t exist.

It was my load that was low, not boost.

 

Interesting point. My previous BOV did leak in high boost, I just replaced it with HKS SSQV-R which doesn't leak. And if your theory is right, maybe that also explains why my load is lower now in comparison.