steven121

iTrader: (27)

I guess im confused a bit, does my timing affect the vacuum at all? Or does timing in the vacuum load area affect mpg?

I dont have any leaks, it has to be my timing, im not sure how to tune timing in vacuim, only boost levels and loads above 100

Raptord

iTrader: (10)

Yes, more cruise timing should result in more vacuum since the engine produces more power at a given tps and rpm.

No, simply exceeding the maximum scale of your load won't trigger boost cut. You'll know if you need to rescale your load axis by looking at your load when logging. If it's higher than your current max in the map, time to rescale.

steven121

iTrader: (27)

[QUOTE=Raptord;10821479]Yes, more cruise timing should result in more vacuum since the engine produces more power at a given tps and rpm.

Ok so when do i stop increasing timing till it knocks like your tuning for boost, or is there a specific timing degree per load like 50-100?

mines5

Today after 600kms of running in a started to give the engine some boost, the engine felt a bit heavy from 3500 rpm till 4200ish rpm. Didnt go past it. Running on low octane today.. Does every rebuild engine responds like this ? or the ecu is still going through the patterns which were followed when the car had no boost ? Or this heaviness will go away once the motor is past 2000 kms ?

domyz

iTrader: (6)

You shouldn't feel that during break in.

Do you mean that you low octane gas or you mean you are on main map which is less agressive?
What is your AFR during those "heavy" transitions?
And post your timing map.

mines5

Hi octane


Low octane



I am using 91 octane pump gas. Sorry but didnt log the AFR, i am new to flash so i dont know how to log AFR, i just dumped the old hand held innovate wideband, i will order an NGK AFX or AEM wide band.

mines5

According to my less knowledge, the evo's ecu learns from previous patterns of ignition and fuel and adapt according to the conditions. The car hasnt seen any boost since 600 kms, can this be a reason of this sluggish /heavy feel ? below 4k revs the car is just so smooth .. OR may be because of the change in compression is causing this. from 8.8 to 8.5 ..

Because of crappy fuel the ecu is just not following neither low nor hi octane fuel maps. Is this possible ?

Raptord

iTrader: (10)

Not really. If the ECU detects excessive knock, the octane flag gets decreased (from an original value of 100). As octane flag decreases, the ECU uses more of the low octane map when calculating what timing and fuel to run.

mines5

any idea about the engine feeling heavy from 3k to 4k?

211Ratsbud

iTrader: (1)

What load do you see at 3-4 k rpm?

domyz

iTrader: (6)

2 things possible for heavy engine out of boost:
Wrong AFR
Wrong timing

Post a log, you can't go blindly on that one.

steven121

iTrader: (27)

anyone for timing on cruise when? My loads look really know, just don't know when the threshold is

domyz

iTrader: (6)

I cruise at 42* for your information, open loop. Stock is 40*.
Cruise timing = Map timing + EGR advance.

42* combined with a leaner AFR seems the consensus for best fuel economy .
15.6:1 for VIII
16.2:1 for IX.

Raptord

iTrader: (10)

Where did you get 16.2:1 for IX's?

domyz

iTrader: (6)

I remember reading Aaron from english racing telling the results from his testing. Somewhere deep in a fuel economy thread.
It was not this particular post, but here is another post where he wrote that: https://www.evolutionm.net/forums/5211099-post8.html