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      06-30-2011, 08:39 AM   #67
m3jasper
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Quote:
Originally Posted by Sal@Evolve View Post
Leaning out AFR is a huge misconception and a generalisation.

Yes, if you have a car that runs from somewhere in the 10's-high 11's, leaning that out to anywhere between say 12.2-13.0 will increase power.

This is used to be the case with much older cars and some modern cars.

Here we are going leaner but we are going from silly rich to AFR for best power.

The lambda target @ WOT for an MSS60 is set as from 13.6 (1000rpm) making it's way towards 12.5 (8500rpm).

Now that's very good for achieving best safe power already and more importantly, consistently.

Leaning out at the higher rpm will only give you a temporary increase in power and even then it will not be much. Even if there was a genuine power increase it's so small that it's just not worth doing.

Ignition timing of course always gives power but the MSS60 already has some pretty radical ignition targets for a stock car. You can see from a recent dyno day that we don't actually run much ignition timing over stock at all. I mean, the ECU is already targeting 32 degrees at WOT high rpm! How much more do you want!

On another post I have shown the full throttle target for ignition (stock). So you can make your own mind up from there if you want to add, or if it's even possible to gain, massive power from ignition.
You can set the targets to what ever you want, does not mean they will be achieved but it's not the best idea in the world to raise them too much.

A combination of CAM timing, ignition timing and changing the allowable maximum torque (these are calculations) gives a very nice safe power increase.

Just going back to the ignition timing again. Even though the targets are set pretty good in the first place, it does not mean that the targets will be met. To make more power more of the time you can 'force' the timing. You have probably seen one other tuner mention this also. This is done by increasing the preset ignition maps.

Some say it's a bad thing, some say it's fine but it all depends on where these maps are preset to. If it's very close to the targets then you already know what's going to happen!
Thanks for the detailed explanation, it's appreciated.

With your primary cat delete calibration, what do you do to compensate for the loss of torque that everyone experiences from 2-3.5k RPM? Are you able to get back the torque that is lost with the cat delete?
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      06-30-2011, 08:56 AM   #68
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Quote:
Originally Posted by Sal@Evolve View Post
Leaning out AFR is a huge misconception and a generalisation.

Yes, if you have a car that runs from somewhere in the 10's-high 11's, leaning that out to anywhere between say 12.2-13.0 will increase power.

This is used to be the case with much older cars and some modern cars.

Here we are going leaner but we are going from silly rich to AFR for best power.

The lambda target @ WOT for an MSS60 is set as from 13.6 (1000rpm) making it's way towards 12.5 (8500rpm).

Now that's very good for achieving best safe power already and more importantly, consistently.

Leaning out at the higher rpm will only give you a temporary increase in power and even then it will not be much. Even if there was a genuine power increase it's so small that it's just not worth doing.

Ignition timing of course always gives power but the MSS60 already has some pretty radical ignition targets for a stock car. You can see from a recent dyno day that we don't actually run much ignition timing over stock at all. I mean, the ECU is already targeting 32 degrees at WOT high rpm! How much more do you want!

On another post I have shown the full throttle target for ignition (stock). So you can make your own mind up from there if you want to add, or if it's even possible to gain, massive power from ignition.
You can set the targets to what ever you want, does not mean they will be achieved but it's not the best idea in the world to raise them too much.

A combination of CAM timing, ignition timing and changing the allowable maximum torque (these are calculations) gives a very nice safe power increase.

Just going back to the ignition timing again. Even though the targets are set pretty good in the first place, it does not mean that the targets will be met. To make more power more of the time you can 'force' the timing. You have probably seen one other tuner mention this also. This is done by increasing the preset ignition maps.

Some say it's a bad thing, some say it's fine but it all depends on where these maps are preset to. If it's very close to the targets then you already know what's going to happen!
Well said, there are also some #'s floating around that are a little 'inflated' for these NA cars. When all is said and done you will be able to feel a difference from a properly tuned S65 motor.
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      06-30-2011, 11:15 AM   #69
Sal@Evolve
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Quote:
Originally Posted by m3jasper View Post
Thanks for the detailed explanation, it's appreciated.

With your primary cat delete calibration, what do you do to compensate for the loss of torque that everyone experiences from 2-3.5k RPM? Are you able to get back the torque that is lost with the cat delete?
Hi,

no worries.

We change the angle of the inlet and exhaust cam at where it occurs and you have to add some ignition also but only in that region.

You can use just use huge amounts of preset ignition too and it's fine too. This is the easy way.

Any decent tuner should be able to do this. It's not very difficult.
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      06-30-2011, 11:16 AM   #70
Sal@Evolve
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Hi Omar,

Thanks.

Yes the numbers are high because tuners will use the first fews vs the later runs to show bigger gains. Did you see the example on M5board recently?
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      06-30-2011, 12:32 PM   #71
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Quote:
Originally Posted by Sal@Evolve View Post
(SNIP)...A combination of CAM timing, ignition timing and changing the allowable maximum torque (these are calculations) gives a very nice safe power increase...

Can you elaborate on "allowable maximum torque"?
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      07-02-2011, 07:18 AM   #72
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Quote:
Originally Posted by wesdobry View Post
Can you elaborate on "allowable maximum torque"?
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      07-02-2011, 09:34 AM   #73
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This is quite difficult to explain.

Let me write something that will make sense.

Just as a beginner - it's to do with the ECU monitoring by calculation the amount of torque the engine is producing. It the torque limits/maps are not changed then your gain in power will be temporary. I am sure you have heard before of stories where the 'ECU adapted back to stock'.

No one explains this because:
1) Not many understand it
2) It's real difficult to explain
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      07-05-2011, 06:59 AM   #74
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Quote:
Originally Posted by niterider
but most importantly the drivers actually feel a difference when driving their cars on the street or racing at tracks.
Ultimately, this is all that matters!! Well said.

If the tune just changed the e-throttle response, similar to what a Sprint Booster does, most people would believe their car gained horsepower as well....
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