Is it possible???

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Apr 8, 2003 | 12:59 PM

#16

Claudius

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My lambda values go from 12.3:1 between 3000 rpm and 6000 rpm to 11.6:1 from 6000 rpm to 7000 rpm to 10.6:1 over 7000 rpm. EGT around 950°C (but I have 2.10 bar boost at 4000 rpm!

)

Apr 8, 2003 | 01:58 PM

#17

twdorris

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From: Frederick, MD

Quote:

Originally posted by Claudius
My lambda values go from 12.3:1 between 3000 rpm and 6000 rpm to 11.6:1 from 6000 rpm to 7000 rpm to 10.6:1 over 7000 rpm. EGT around 950°C (but I have 2.10 bar boost at 4000 rpm! )

Damn that sounds like a fun ride. All the right numbers in all the right spots. The EGT is a bit higher than I might have expected. Is that sustainable on a road course or is that a setup for a pure power pull?

As for the airflow fuel cut, it won't be based strictly on MAF Hz reading. As I think someone else posted ealier, it will factor in air temps and baro pressure too, but it also includes RPM... It's basically an "air mass per rev" comparison. Which is why the fuel cut might not happen one day when it's 60F out, but might the next when it's 30F. More mass requires more fuel which is what the real limit is based on...the fuel requirements for the given airflow. If the fuel requirements exceed the capacity of the factory fuel system, the ECU cuts the motor.

Thomas Dorris

Apr 8, 2003 | 02:33 PM

#18

Claudius

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Quote:

Originally posted by twdorris
Damn that sounds like a fun ride. All the right numbers in all the right spots. The EGT is a bit higher than I might have expected. Is that sustainable on a road course or is that a setup for a pure power pull?

I use an AVC-R in addition to the ECU, so I have 3 programs: one "OFF" with 0.85 bar boost, one "A" with a sustained 1.5 bars for daily driving around and one "B" with 2.10 bars peak for the twisty roads

EGT was pretty stable when setting the ECU with the wideband O2 sensor connected (on the road) but went higher on the dyno with that tiny fan

Quote:

Originally posted by twdorris
As for the airflow fuel cut, it won't be based strictly on MAF Hz reading. As I think someone else posted ealier, it will factor in air temps and baro pressure too

I guess that was me?

Quote:

Originally posted by twdorris
If the fuel requirements exceed the capacity of the factory fuel system, the ECU cuts the motor.

Yes, but there's a lot of safety margin in that program. The stock fuel pump can supply fuel for about 22 PSI held boost IIRC, especially if you bridge that relay to increase the voltage.

Apr 8, 2003 | 05:26 PM

#19

twdorris

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From: Frederick, MD

Quote:

Originally posted by Claudius

Yes, but there's a lot of safety margin in that program. The stock fuel pump can supply fuel for about 22 PSI held boost IIRC, especially if you bridge that relay to increase the voltage.

Certainly, there is some safety margin there. The basic idea, though, is to limit the airflow to roughly the point where the fuel system is really starting to get taxed. I suspect that safety margin is even larger on the US EVO8 because the fuel system already has the classic fuel pump "rewire" mod done feeding voltage over nice fat wires straight from the battery during WOT operation.

Thoma s Dorris

Last edited by twdorris; Apr 8, 2003 at 05:31 PM.

Apr 8, 2003 | 06:03 PM

#20

rt turbo

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From: Mooresville, NC

caludius, what kind of wideband o2 do you have? how much was it?

Apr 8, 2003 | 06:54 PM

#21

Claudius

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Quote:

Originally posted by rt turbo
caludius, what kind of wideband o2 do you have? how much was it?

I have a SARD A/F DEVICE. Cost was approximetely $1,000.

Apr 9, 2003 | 01:10 AM

#22

Drivemecrazy

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Joined: Mar 2003

Posts: 39

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From: CA

Quote:

Yes you did ... But I have never seen more than 1900 Hz on my PowerFC...

You right, AFS's nomailly output is 18.75Hz~1600Hz

Quote:

You mean it "drives you crazy"? I understand you very well! Where are you from?

I'm from KOREA. I like EVO serise and
Now I live in Diamond bar, CA.
I've doing ECU tune in KOREA.

Quote:

Well, I think Mitsubishi programmed a fuel cut into the ECU when Karman frequency =1700 Hz and temp = 18 or 20°C at 1000 mmHg barometric pressure.

You right.
for Boost control,
First value is AFS's OUT put
but in USDM EVO8 ECU not set AFS freq.
It's value is like EVO5 RS (6350Hz)

Quote:

Yes, that what I use the SARD ANALYZER for

You can see it here (in Kanji I think): http://gooparts.com/special/spe8/08.html

Umm, that's good stuff. I'm use MOTEC PLM

Quote:

Yes, it's higher at idle: 6 bars.

Good job. If no fuel delivery problem, I think you'd better change
more big size injector.

Last edited by Drivemecrazy; Apr 9, 2003 at 01:34 AM.

Apr 9, 2003 | 04:43 AM

#23

Claudius

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Thanks for all the info, Drivemecrazy

I plan on getting 720cc/min injectors to get below 80% duty cycle. Maybe SARD injectors with the SARD fuel rail? (this is for an Evo 6) What would you suggest? I was also thinking maybe a bigger MAF (RB26 maybe?). Thanks

Apr 9, 2003 | 12:57 PM

#24

Drivemecrazy

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Joined: Mar 2003

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From: CA

Quote:

Originally posted by Claudius
Thanks for all the info, Drivemecrazy
I plan on getting 720cc/min injectors to get below 80% duty cycle. Maybe SARD injectors with the SARD fuel rail? (this is for an Evo 6) What would you suggest? I was also thinking maybe a bigger MAF (RB26 maybe?). Thanks

Umm... Cool.
In my experience. 75~80% duty is safety and max for
Engine...

See atached image. I don't know exactly.
May be your injector looks like that.
That type injector still small size than EVO's stock.
May be HKS ready to sell 820cc in japan.

Other way is change to top feed type injector,
Fuel rail. but this mod. need change injector connector too.

About MAF... as far as I know.

no bigger type for EVO, EVO's AFS is Kalmann vortex type.
But most Japanese car's AFS is Hot film or Hot wire.
RB26's type to Hot wire,

If you use HKS F-Con V Pro, you can remove stock AFS.

Attached Images