AVCS - Intake and Exhaust Timing

[Nah]

Originally Posted by Wayno

Have used used the avcs tables from the OFH maps?

Nah I'll go check that out now

[shr133]

Originally Posted by Wayno

Why so many changes? How do you test it all so thoroughly that you don't lose power?

If I cared about Stg1, which trust me I don't, I wouldn't make so many changes, besides restore the AVCS under 3000 where the OEMs new what they were doing.

I test 1 area of the map at a time and I've been tuning for a long time...
I keep it simple....
The engine is just an air pump so a change either helps or hurts....

Below 3000 rpm the map sucks, way too much exhaust timing...

I've smoothed out the map and fix all the faults...

I'm getting really close to a perfect map for a NA auto.....

[shr133]

Changed back to this map with slight mods... NA / Auto.....

I run simple maps the cams won't move as fast as the map so simple maps run very smooth with no lags or flat spots....

You have to bump up the timing at low rpm to get the cams to open faster over 3000 rpm....

Too much timing hurts power, sounds cool but won't pull as hard....

This is still my do it all map and comes on strong by 3000 rpm....

Slightly weak at 80% below 2000 rpm a bit of a trade off....

[KoolBRZ]

Originally Posted by shr133

Changed back to this map with slight mods... NA / Auto.....

I run simple maps the cams won't move as fast as the map so simple maps run very smooth with no lags or flat spots....

You have to bump up the timing at low rpm to get the cams to open faster over 3000 rpm....

Too much timing hurts power, sounds cool but won't pull as hard....

This is still my do it all map and comes on strong by 3000 rpm....

Slightly weak at 80% below 2000 rpm a bit of a trade off....

I'll try running your tables if you try running my tables, shown in this post, http://www.ft86club.com/forums/showp...&postcount=214 , but you would also need to change your Port Injection by reducing it to the bare minimum, as shown in the pic below. Like running E85, timing can be advanced more with less engine knock, since DI is less prone to pre-ignition. I'm running the timing advance map for 93 Octane, but burning 91 Octane, and my IAM stays rock-solid at 1.0. Now that I've got a good set of AVCS maps with DI, I'm going to start adding PI back in, pulling timing advance where it starts to knock. All the experienced tuners recommend tuning with DI first, then adding the PI back in.

[KoolBRZ]

Originally Posted by KoolBRZ

I'll try running your tables if you try running my tables, shown in this post, http://www.ft86club.com/forums/showp...&postcount=214 , but you would also need to change your Port Injection by reducing it to the bare minimum, as shown in the pic below. Like running E85, timing can be advanced more with less engine knock, since DI is less prone to pre-ignition. I'm running the timing advance map for 93 Octane, but burning 91 Octane, and my IAM stays rock-solid at 1.0. Now that I've got a good set of AVCS maps with DI, I'm going to start adding PI back in, pulling timing advance where it starts to knock. All the experienced tuners recommend tuning with DI first, then adding the PI back in.

@shr133, I've been working on AVCS tuning for a long time, and have concluded that, just like you say, too much timing hurts power. Too much timing wastes fuel as well. I have a question for you @shr133. Do you think there is a distinctive sound when part of a tune is just right? Because I think there is. I think of it like a double-beat island in the middle of a single-beat ocean. @shr133's tables haven't worked for me in the past when I was still using Port Injection, but using Direct Injection most of the time, like shown above, works perfectly with your tables. I think of it like a double-beat ocean with a few single-beat shoals here and there. I haven't run the tables long enough to find out if it stays in tune yet though. I think tuning by sound could make things a lot easier, if there was only a way to log it.

[freerunner]

Originally Posted by Wayno

These do fix for the most part the bogging/shifting to around 2200 in auto mode.

I wouldn't change the timing so much from shiv's dyno tuned timing at WOT for NA though.

Would be interesting to see if these would benefit uel and short el.



MT EL E0 Exhaust


MT EL E85 Exhaust

Quick report:
The E85 exhaust timings @3600 rpm should be default for any stg1 tune. Noticeable gains in the torque dip region.

Tested with 100 ROZ and catted stock header.

Here's a pic of my Frankenstein avcs exhaust map:

[KoolBRZ]

Originally Posted by shr133

Changed back to this map with slight mods... NA / Auto.....

I run simple maps the cams won't move as fast as the map so simple maps run very smooth with no lags or flat spots....

You have to bump up the timing at low rpm to get the cams to open faster over 3000 rpm....

Too much timing hurts power, sounds cool but won't pull as hard....

This is still my do it all map and comes on strong by 3000 rpm....

Slightly weak at 80% below 2000 rpm a bit of a trade off....

I really like your maps...., but not with conventional DI/PI tables. I really like the sound and the acceleration with the "DI-Mostly" table I posted above. I finally tried using conventional DI/PI tables with your maps, and it just wasn't as much fun to drive. @shr133, no matter what you think of me, you're missing out on something if you don't at least try your maps with some "DI-Mostly" tables in your tune. Remember, you can also use more spark advance with DI, than you can with PI, so, a tune with "DI-Mostly" tables can run with more spark advance.

[shr133]

Originally Posted by KoolBRZ

I really like your maps...., but not with conventional DI/PI tables. I really like the sound and the acceleration with the "DI-Mostly" table I posted above. I finally tried using conventional DI/PI tables with your maps, and it just wasn't as much fun to drive. @shr133, no matter what you think of me, you're missing out on something if you don't at least try your maps with some "DI-Mostly" tables in your tune. Remember, you can also use more spark advance with DI, than you can with PI, so, a tune with "DI-Mostly" tables can run with more spark advance.

Thanks.....

You have to adjust the cams, fuel and timing together....
I started by getting rid of all the holes and weird stock settings, that made a huge difference and now I just keep fine tuning.......

The DI/PI map is an example of what doesn't work....
You can't turn the PI on / off and on again, just doesn't work You have to run PI all the time just change the percentage or don't run PI but not both...
I like 20% over 2000 rpm...... toyota got that part right.

[shr133]

Originally Posted by KoolBRZ

I'll try running your tables if you try running my tables, shown in this post, http://www.ft86club.com/forums/showp...&postcount=214 , but you would also need to change your Port Injection by reducing it to the bare minimum, as shown in the pic below. Like running E85, timing can be advanced more with less engine knock, since DI is less prone to pre-ignition. I'm running the timing advance map for 93 Octane, but burning 91 Octane, and my IAM stays rock-solid at 1.0. Now that I've got a good set of AVCS maps with DI, I'm going to start adding PI back in, pulling timing advance where it starts to knock. All the experienced tuners recommend tuning with DI first, then adding the PI back in.

I may have to try running more DI at low RPM, It was working good so I have not messed with it for a while.......

[shr133]

Originally Posted by KoolBRZ

@shr133, I've been working on AVCS tuning for a long time, and have concluded that, just like you say, too much timing hurts power. Too much timing wastes fuel as well. I have a question for you @shr133. Do you think there is a distinctive sound when part of a tune is just right? Because I think there is. I think of it like a double-beat island in the middle of a single-beat ocean. @shr133's tables haven't worked for me in the past when I was still using Port Injection, but using Direct Injection most of the time, like shown above, works perfectly with your tables. I think of it like a double-beat ocean with a few single-beat shoals here and there. I haven't run the tables long enough to find out if it stays in tune yet though. I think tuning by sound could make things a lot easier, if there was only a way to log it.

You can hear it through the intake, definitely sounds cool when its working right...

This last map seams to run better and better with the computer learning....
I try a few maps than run it for a few weeks to see how it works...
This map is really close...
A few more tweaks and I'll move on to other tuning like MAF and other maps...

I've been tweaking the injection angle, that map was messed up also...

[KoolBRZ]

Originally Posted by shr133

You can hear it through the intake, definitely sounds cool when its working right...

This last map seams to run better and better with the computer learning....
I try a few maps than run it for a few weeks to see how it works...
This map is really close...
A few more tweaks and I'll move on to other tuning like MAF and other maps...

I've been tweaking the injection angle, that map was messed up also...

What do you think about the idea of tuning with sound? I think a microphone placed under the radiator, facing back, could pick up the tone of the tune, so to speak. If it could be logged along with the rest of the readings it could be used to tune with.

[Kodename47]

Originally Posted by shr133

The DI/PI map is an example of what doesn't work....
You can't turn the PI on / off and on again, just doesn't work You have to run PI all the time just change the percentage or don't run PI but not both...
I like 20% over 2000 rpm...... toyota got that part right.

How have you validated this statement, other than "feel"?

Originally Posted by shr133

I've been tweaking the injection angle, that map was messed up also...

Really.... you think the OEM spent ages figuring out injector angles (and DI ratios) to get it wrong? What specifically have you changed?

[KoolBRZ]

The OEM spent ages getting the best out of a restrictive exhaust system, once that is changed, a lot of the OEM tables become way off. Imagine the velocity of the charge with a Cat, and without Cats. That's why the tables need a change. The velocity has changed.

[Kodename47]

Originally Posted by KoolBRZ

The OEM spent ages getting the best out of a restrictive exhaust system, once that is changed, a lot of the OEM tables become way off. Imagine the velocity of the charge with a Cat, and without Cats. That's why the tables need a change. The velocity has changed.

Right, so how do DI angles and ratios effect "velocity" exactly? Or maybe the question should be that why does a change in "velocity" require a change to these tables.

Maybe showing an example and explaining changes rather than....."cuz I like it". If only we knew what these guys did.....

Or maybe I could test using the same technique.