VEMS I5 Maps

[Jamo]

How come you haven't reduced the timing if it's knocking?

The timing is less than on A80avants car, it's subjective to the engine setup anyhow, if it's knocking it could also be your MAT is high.

Have you logged and checked what your EGT's and MAT's are around the knock area?

[th.b.w.]

EGT is about 800°C , MAT 30-40°C

I haven't noticed knock.....

Now i know i have on cyl 3 and 4 .....


Thomas

[GazzaG60]

my timing is about the same as Vas has. he has more in some areas than me but i think thats turbo dependent too. i got a few degrees here and there in the kit bag still i think.

i can tell this by the changes in cell to the egt.


illpost a map soon. probly not to many's taste my setup but there goes. also its 1.1.23rc. im yet to upgrade.

[A80Avant]

i have high timing on cruise and recently uped it a bit till 140kpa. Still working on how the car behaves in cruise. However as megatune does only have a generic IAT to timing curve reduction, it may be that you are knocking because it is not retarded enough for those temps.

having said that my motronic kept that timing up to 44C IATs which i somehow dont believe as i have seen some old vagcom logs

[Billman]

i advanced the timing and it sounds much better now but i was not able to make longer runs since is pouring today.

the EGTs are still very low (but still it is a short run so there is no time to raise much).

[Jamo]

i have high timing on cruise and recently uped it a bit till 140kpa. Still working on how the car behaves in cruise. However as megatune does only have a generic IAT to timing curve reduction, it may be that you are knocking because it is not retarded enough for those temps.

having said that my motronic kept that timing up to 44C IATs which i somehow dont believe as i have seen some old vagcom logs

He's on 1.1.64 I think so it's vemstune with the retard table.

30-40c is high, I need to get the 1.8t MAT in mine to double check but 1.7 bar and 17c temp, tribute to Wagner IC!

[A80Avant]

ah i see.
then ill have a look at the map soon

if pistons are OEM, then the knock could be because of them. I know of a stock rs2 with similar map to mine, and it knocks like crazy above 1.3bar

[loxxrider]

why do you think the knock is because of stock pistons? Do you mean because of stock compression ratio?

[Jamo]

Stock CR will be more sensitive to high MAT temps and increased boost causing knock / detonation.

Reverse manifold always help here and a good IC

Seen some cars tuned well on stock pistons however

[Billman]

Stock CR will be more sensitive to high MAT temps and increased boost causing knock / detonation.

Reverse manifold always help here and a good IC

Seen some cars tuned well on stock pistons however

Dont see how the reversed manifold helps there but i am with you on the rest.

[A80Avant]

he is referring to the IATs that the reverse manifold can help keep low

[loxxrider]

right, I was curious to see if he meant because of dome design or something of the sort. I understand how higher CR is more prone to knock. I have had some thoughts on this. I'm not an advocate of running lower CR unless its absolutely necessary to avoid knock. On race gas, meth, or E85 this is especially true. Thats for another thread however.

BTW Jamo, I decreased req fuel by about .57 and increased VE map by the same factor. The car runs exactly the same but seems to be more responsive to small adjustments to the VE map. I also increased the MAP samples to 10 as you suggested. I was able to turn the boost up to roughly 17psi (or 216 kPa) and did some more fuel tuning to get it closer to .85 lambda. Its still rough, but better than before. I'll post the map as soon as I get a chance to grab it out of the ECU. Still needs about 5 degrees all over the timing map and probably more in some places. I'll be sure to keep this updated with new and improved maps.

[Billman]

he is referring to the IATs that the reverse manifold can help keep low

Thats what i dont see. The surface of the intake path is very low in order to exchange enough heat and raise the IAT because tha air mass is very high.

[Jamo]

Thats what i dont see. The surface of the intake path is very low in order to exchange enough heat and raise the IAT because tha air mass is very high.

Datalog the the temps of a reverse car and then compare it to the same spec car without the reverse and you will see a big difference in temp.

The intake pipe heatsoaks badly on the stock setup, the plastic pipe isn't as bad on the RS2 for this even then.

[Billman]

check my log above. It is with 13 degrees outside temp and gives 22 at 1.3 bar. I have big IC.

apart my RS2 has no plastic pipe :-D (factory spec)