Knock fix with Australian Fuel 98/100 RON

[steve99]

Originally Posted by chickencornsoup

well done steve,

dumb question: will it cause any engine damage for the level of knock you have seen on OFT tune 1.5x ?

As I said in original post I'm not a tuner , however I think its unlikley that it would cause engine damage , the ECU manages knock in a couple of different ways. When the ECU manages knock it tends to pull way more timing than necessary. By removing about half the timing the ecu would remove you can stop or eliminate the knock. The ECU also tends to remove timing over the entire RPM/LOAD range (IAM Drop) even if the knock is just in the 2000-3000 rpm range . Even with the adjusted ROM the ECU is still able to manage knock in its usual way so if you put 95 in it it would still drop IAM and manage knock.

[w00t692]

Most stock tunes base their knock tables around a known fuel value that the manufacturer tunes them for, and then they scale back ignition timing based around knock levels.

For instance, Honda knock maps are tuned around 95 octane fuel, and scale back based on knock level, which is tuned with a "knock ignition limit" table that tells it how much it can retard ignition based on fuel quality.

[steve99]

Originally Posted by AL008

I installed my overpipe and new Grimmspeed Headers gaskets because there were little leaks. This is my new datalog in 3rd gear:

http://www.datazap.me/u/toy-sooby/3r...e?log=0&data=1

What ROM and fuel are you on ? standard headers cat ??

[AL008]

Originally Posted by steve99

What ROM and fuel are you on ? standard headers cat ??

I had one modified from Shiv to pull about 1-2 degrees of timing throughout the range of loads. I think Load above 0.8 had 2 degrees timing pulled.

Here are the differences in Timing Pulled:





I am running Revworks UEL, 2.5" overpipe, Perrin catted front pipe, Perrin Resonated Catback and drop in filter. All on RON 98.

[steve99]

Originally Posted by AL008

I had one modified from Shiv to pull about 1-2 degrees of timing throughout the range of loads. I think Load above 0.8 had 2 degrees timing pulled.

Here are the differences in Timing Pulled:





I am running Revworks UEL, 2.5" overpipe, Perrin catted front pipe, Perrin Resonated Catback and drop in filter. All on RON 98.

Yes thought it looked very good and thats why , think it was money well spent
They have probably made other changes to fueling, MAF as well.

[AL008]

Originally Posted by steve99

Yes thought it looked very good and thats why , think it was money well spent

Do you think it's worthwhile for me to either try run the stock stage 2 UEL tune again to see if it is better, or just advance 0.5 degrees of timing in those cells to see if I can squeeze a little bit more out of it?

Thanks Steve.

[steve99]

Originally Posted by AL008

Do you think it's worthwhile for me to either try run the stock stage 2 UEL tune again to see if it is better, or just advance 0.5 degrees of timing in those cells to see if I can squeeze a little bit more out of it?

Thanks Steve.

Mate I would stick to what the Openflash Vishnu tuning guys gave you its a custom tune based on your mods and they have years of experience.

[AL008]

Originally Posted by steve99

Mate I would stick to what the Openflash Vishnu tuning guys gave you its a custom tune based on your mods and they have years of experience.

It wasn't really a custom tune, but just a conservative one that he said will solve the knock problems.

[steve99]

Originally Posted by AL008

It wasn't really a custom tune, but just a conservative one that he said will solve the knock problems.

The Stage 2 EL tune runs more timing advance than stage 1
Maybe if you run 100RON fuel it might be worth trying the original Stage 2 tune.

[steve99]

Originally Posted by w00t692

Most stock tunes base their knock tables around a known fuel value that the manufacturer tunes them for, and then they scale back ignition timing based around knock levels.

For instance, Honda knock maps are tuned around 95 octane fuel, and scale back based on knock level, which is tuned with a "knock ignition limit" table that tells it how much it can retard ignition based on fuel quality.

Basicly that our problem in Australia. Our 98 RON is not as good as your 93 AKI that the OFT maps are tuned for.

we also get knock on the stock tune as well even on 98/100 RON

[Kodename47]

Originally Posted by AL008

Do you think it's worthwhile for me to either try run the stock stage 2 UEL tune again to see if it is better, or just advance 0.5 degrees of timing in those cells to see if I can squeeze a little bit more out of it?

Thanks Steve.

If you're running a UEL manifold, you could always copy the AVCS maps from the stage 2 into the map you have and see how that runs. From memory the stg 1/stg 2 maps don't differ much apart from the can timing.

If you're willing to take time and log the car, you could always slowly increase timing and then drop it back when you see knock.

[steve99]

Originally Posted by Kodename47

If you're running a UEL manifold, you could always copy the AVCS maps from the stage 2 into the map you have and see how that runs. From memory the stg 1/stg 2 maps don't differ much apart from the can timing.

If you're willing to take time and log the car, you could always slowly increase timing and then drop it back when you see knock.

They add about 1-1.5 deg timing advance and a bit richer AFR target 0.3 aprox from memory as well at cam timing


see here for graphic illustration of how poorly our fuel performs.

http://www.datazap.me/u/toy-sooby/ca...-11-12&solo=11

http://www.datazap.me/u/toy-sooby/3r...=0&data=1-8-12

[uncivilised]

good work with the tunes, ill keep a copy of this for the future.

[keen as]

Thanks. I will give the 98 tune a go.
On the OFT, I can see IAM to monitor.
What is the other parameter to monitor? Is it KC?
Thanks again for sharing