Modified IDM and tuning

[907DAVE]

Originally Posted by Colt

If all the expansion is taking place in the combustion chamber, you lose heat in the exhaust which means you lose expansion that would be used to spin the turbo.. So yeah, you'd have better fuel economy, but the turbo would spool slower...

So I was looking into ways to exploit this a bit and realized the majority of the base SOI maps already have a pretty significant drop in the low RPM - high MFD ranges - then timing picks back up as the RPM's climb.

Is this in there just for this reason (turbo spool), or is there more to it?

Sorry Colt, little off topic.

[Colt]

Bah, I never believed in staying on 1 topic, when things get off topic, thats when ya really start learning things and how they relate to one another. I could never stay on just 1 topic anyways, too many other things to talk about

[907DAVE]

To those who have not seen the stock PMT1 base SOI map, here is what I am talking about.



Then from there on out the timing advances to a whopping 7 deg. - then factor in the delay (18ish) and you are up to around 25 BTDC @ 3200 RPM.

Mods, I am not sure what maps I am allowed to post.

Please delete if necessary.

[cleatus12r]

Post away. I've gotten much more in detail than that.

Wanna know why the SOI map does that?

Take a look at the desired ICP map and ask yourself what ICP does to the start of combustion event depending on pressure.

[Shaw]

hmm, since you brought that up, Ive been wanting to ask. Why the drop in the middle of desired ICP map? Does it have to do with the stock hpop not being able to handle it?

[cleatus12r]

[907DAVE]

LOL.........

Originally Posted by cleatus12r

Take a look at the desired ICP map and ask yourself what ICP does to the start of combustion event depending on pressure.

When I raise or ramp up the ICP I will try and drop SOI a degree or two in those ranges because of its affect on SOC.

Based off the stock SOI map it appears that they are dropping close to 10 degrees. Is this drop ALL because of ICP, or could some of it be for turbo spool?

[cleatus12r]

I certainly wouldn't worry about dropping the base SOI map due to ICP changes.

I'm stupid-conservative when it comes to my SOI. I smooth out the map and give it a nice, flowing look which will raise the map ever-so slightly right in the center but lowers it a little in others......just so it looks like a smooth, rolling wave. As far as values go, none of them are changed more than 2 degrees in either direction.

[Shaw]

First off I like to know about the fritos dip - is it any good?

Next why wouldn't the map look like this? HPOP is my guess.



When I run it with this map It doesn't seem to have any problems but I do have big oil?