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Current mods are: 3" RMR turbo back with 2.5" Random high flow cat, K&N stock air filter, Greddy type-S DV, Prfec B spec II EBC, and a Alamo/Unorthodox under drive crank pulley.

Run 11 (green) is with out the under drive pulley, running 1.3-1.25 boost.

Run 14 (red) is with the under drive pulley and same boost 1.3-1.25 boost.

Run 19 (blue) is with the under drive pulley and running 1.4-1.35 boost.

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Here is the A/F recorded on the last run, interesting to note that the actual dips and spikes in engine output trail the measured A/F values by about 200-300 RPM.

broeli

iTrader: (19)

You don't have an SAFC or anything? The crank pulley looks to be a good mod. Just not sure if I want to do it or not though. I've done it on all my previous cars. The stock pulley is basically a harmonic dampner with a zero balance correct. Which means it is not balanced with the rest of the assembly such as crank, flywheel BUT it does serve a pupose in reducing engine vibrations, etc "dampening" them. Which in turn puts less strain on the main bearings and lower end of the motor.

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Nope, I have a stand alone ECU comming very soon though . Here is a graph show another EVO tested on the same day. It had very similiar mods plus the Works reflashed ECU for a stock car.
Now before every one starts bashing Works there are a few things that you need to be aware of. This refash is for a stock car, and was not programmed for the mods on the car. He was also using a MBC, while he started at 1.4 bar his boost dropped a lot more than mine 1.4-1.2. From what I am told the works ECU advances the timming in the lower rpms to get the boost to come up faster, on a stock car that works fine. When you increase air flow through exhaust, intake, and boost, that much advance can cause knock retard, ruining the boost response and causing power loss. This is why Works tells every one not to raise the boost or add other mods to the stock ECU flash. If your going to make changes like this, you need to adjust your fuel/ignition timming accordingly. This is why stock cars respond well to the Works reflash for a stock car, and modified ones do not.
With that said let's look at some interesting aspects of this graph. Even though he was experiencing knock retard and lower boost in the higher rpms, he still managed to carry more HP in the upper end due to the A/F ratios. I can see how people are able to get over 300WHP with similiar mods and an AFC. You can also see that works actually adds more fuel on the lower rpms, this is what give the better drivability that all of the works customers talk about. I have a wide band A/F permenantly installed so that I can fine tune on the street when my stand alone comes in. I also feel that the stock ECU part throttle low rpm fuel ratios are a little lean, this is what causes some of the minor surging/hesitation at part throttle.


I have another thread that talks in more detail regarding the Under drive pulley, check it out and please post your thoughts and questions about the pulley on that thread.

https://www.evolutionm.net/forums/sh...threadid=38024

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BTW these A/F readings were taken after the high flow cat in both cars so the actual A/F ratios may be a little richer than what is shown here. There is some debate over that, but my wide band mounted in the down pipe seemed to show similiar numbers, but without data logging that O2 sensor it is hard to say for sure. At most the actual A/f might be only slightly richer, plus these readings seem to match what I have seen recorded by others.
The stock O2 sensor in the turbo exhaust housing did not want to come out, so....

Stinkapuss

iTrader: (10)

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Very impressive for having no fuel management!