Ford Focus RS Tuning

Hey guys,

I tuned a Ford Focus RS for the first time this past weekend, had a very positive experience and result on the car. My question, do any of you guys know how much boost the 2.3L in the RS can take on the stock turbocharger? I have it dialed in at a max boost of 24.5-25psi. I have seen some reviews of Cobb tuning base maps being around 25.5 psi and Mountune around 27psi. I will be testing 26-27psi soon to see if there is positive result without any negative effects. The car has an aftermarket intercooler and it does a very good job. Any help would be appreciated.

~Kris

Also, has anyone ever gotten a "P0171 code, system too lean?" I have never seen this code on all of the ecoboosts I have tuned, except for this RS. Not sure what triggered the code, but it came on after all tuning was done and customer was on his way home with the car, go figure...

~Kris

*Update*

CEL fixed, determined the issue was incorrect fueling at idle on Mapped Point 0. The car was adding 30% of fuel at idle, creating the "system too lean" condition. I currently have the car running around 26psi, using the Ford Throttle Control logic to regulate boost, the car is very responsive and the power is strong. I am now hitting a turbo FMEM limit around 4900rpm, the load on the RS seems to hit it's highest point around 4500, so I feel it is triggering the LSPI tables some way, shape, or form. Even though FMEM max is 3.0 load, I am not hitting it but it must be hitting one of the other tables triggering the limit. I will do more testing and report my findings.

Kris

*Update*

All load limiters are eliminated, only throttle control action the engine is doing is to regulate boost in the midrange. Car is running very strong.

Kris

What limiter was it?

The LSPI tables, the RS wants to hit it's highest point of load around 4000-4500rpm, that was it.

Kris

Nice work. I would like to play with one of these myself.

Appreciate it. I didn't want to push the boost too hard on my first RS customer, so the current boost at 25psi felt very stout. The car ran decent timing during the power curve as well.

Kris

Hi Kris5597,

I'm tuning a Focus RS for the first time with HPTuners and I'm getting FMEM limit and sometimes LSPI. Could you help me with your tables in order to compare them. I've being increasing these tables step by step because I don't like setting highest numbers on those tables.

Thanks.

Quote:

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Originally Posted by kris5597

Appreciate it. I didn't want to push the boost too hard on my first RS customer, so the current boost at 25psi felt very stout. The car ran decent timing during the power curve as well.

Kris

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Quote:

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Originally Posted by dperformance

Hi Kris5597,

I'm tuning a Focus RS for the first time with HPTuners and I'm getting FMEM limit and sometimes LSPI. Could you help me with your tables in order to compare them. I've being increasing these tables step by step because I don't like setting highest numbers on those tables.

Thanks.

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dperformance the lspi tables tend to track pretty closely from what you have in the tables vs what you’re logging. The turbo airflow tables and max turbo temperature tables (those tables typically cause turbo fmem) don’t tend to reflect table values in the scanner. My assumption has been those tables values work off something like a ‘test condition’ value, then allow lower actual values based on you’re current conditions. Basically you’ll need to increase the turbo tables in comparatively larger jumps than you need to increase the lspi tables, and the values will look higher than you’re actual goal max value would be,