Dixit

iTrader: (1)

So Bink and a few others mentioned that I should use .0320 for the ETC scaler for a 90mm TB instead of using the stock .0255 scaler. Well I put the .0320 in and it worked great.

But then I read Phil99's post about adjusting the ETC Scaler till I get as close to the MAF/Dynamic Airflow.

Well at .0320 is off by about 1.50 g/sec. When I dropped it to .0275 I noticed it was only off by about 0.75 g/sec. Im sure if I drop it back to stock value of .0255 it will be almost dead on with the MAF/Dynamic Airflow values. Why is this?

BTW Im using a LS2 90mm TB that was high ported and well done by Tony Mamo.

Dixit

Phil99vette

iTrader: (11)

Mine is @ .0225 and the numbers are pretty close to dead on.
Phil

Dixit

iTrader: (1)

So then the whole .0320 scaler figure that everyone says to "set it and forget it" (Ronco ) is basically wrong.

Wierd how you got .0225 and its dead on and its lower than stock.

Dixit

SideStep

WAIT a minute??

I thought the below was accepted as the correct settings:

-For a C5 the "ETC Scalar Area" is adjusted - not the effective area.
-For a 90 mm TB a value of .0320 works well for most.
-Ported 78 mm TB would be between .0255 and .0320 ??

Dixit, what parameters (PIDs) are you scanning to see the error?

I was getting ready to buy a 90/90 setup and I thought I had done all the home-work...

Dixit

iTrader: (1)

Well I guess that accepted number may be wrong. Cause using Phils method of aligning it as close to the MAF/Dynamic Airflow definetely put the number close or lower than stock.

I had it at .0320 and it ran fine. But when I set it to .0275 it idled fine but didnt drive it. Im going to set it back to .0255 tomorrow and see if that puts me inline with my MAF/Dynamic Airflow and see how it drives. Im using MAF Airflow g/sec, Dynamic Airflow g/sec and Idle Desired Airflow g/sec.

Dont get me dont SideStep, the .0320 worked fine, but if the idle desired should be as close to Dynamic/MAF then that number aint what I want on there. I will let you know tomorrow how it drives going to work.

Dixit

Phil99vette

iTrader: (11)

The big key with the C5 is the idle learn so you can be off and still have it idle. Here's my thoughts....
If a 90mm flows more air than a 75mm
I.e. 275cfm vs 250 cfm @ same step....
To get it to see the same CFM @ the same step....
You would need a smaller number to scale it back.

I am probably wrong but just my .02...

Bink

Depends on IAC Park Values, RAF values and LSA of cam (RAF is LSA dependant). Stock IAC Park values and Big cam (stock cubes) with narrow LSA don't work well with lower ECT scalar values. RAF values larger than IAC Park values don't work very well on my car.

Dixit

iTrader: (1)

Well just drove to work with .0255 as the scaler value and its almost dead on, its off about 0.20g/sec right now at idle compared to the MAF/Dynamic Airflow values. Idle seemed to hunt for the first 5-10mins when I'd come to a stop but after that the idle stuck everytime at my set 900rpm value. My IAC Park values are stock. RAF has been tweaked to be on point as well, but will have to do it again since looks like the .0255 scaler is the one Im going to stay with.

Dixit

SideStep

Guess I am waiting until March to figure it all out... tax returns... also replacing current cam with 226/230 112lsa (+0) XE-R type...

Phil99vette

iTrader: (11)

Whats ironic.....
If your airflow is .20 high....
lets say 1.90 to 1.70
= 89.4% off....
.0255 * .894
0.0228

Which is about what mine is...

Dixit

iTrader: (1)

Right but is odd is that during startup the Desired Idle is high about 1.00g/sec and then the MAF/Dynamic becomes high by about 0.20g/sec. I imagine this is because of the startup initial that adds. I got a feeling if I go to .0225 the startup going to be off by about 2.00g/sec and maybe dead on warmed up, dont know if there is any harm in that.

Also if you use smaller values the percentage will be lower, IE, if you go 8.6 compared to 8.8g/sec you are only off by 97.7%

Dixit

Phil99vette

iTrader: (11)

One thing that I have found is that all of the tables need to work together. It will be interesting to see how my current tune works with the new camshaft in my 346"(254/260 .650 112 + 2)
Phil