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My build did not use +2mm pistons, the pistons were stock. Erion cam set to my specs not theirs. Stock ignition timing. Head was mildly cleaned up with a good valve job. Head milled .022 and a .030 head gasket from cometic. Akra header and PC3. We could not get the A/F richer than 13.4/1 because of the limitation in the PC3 that DJ put in. On another friends 98 BB with more head work and +2mm pistons we got 177 RWHP. Later on the same 98 with the addition of a +2mm crank we got 188 RWHP. Just my experience
 

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My build did not use +2mm pistons, the pistons were stock. Erion cams, Head was mildly cleaned up with a good valve job. Head milled .022 and a .030 head gasket from cometic. Akra header and PC3.
Ah ok, sounds like we have similar setups. You just have a bit more compression with the head mill.

We could not get the A/F richer than 13.4/1 because of the limitation in the PC3 that DJ put in.
?? First time I've ever heard about PC3 fuel limitation... I actually have to remove fuel for my whole map, every number is a negative value. I can still can easily tune to mid/high 12's A/F in the upper ranges. But, I'm also running the Gen II fuel pressure regulator so I think my rail pressure bumped from 45 to 50.


the same 98 with the addition of a +2mm crank we got 188 RWHP
Sweet! I've actually had a second low mileage motor for years now I interned to do a full build on (may still) but where I'm at now is already so much overkill for riding around the Wash DC area its hard to justify spending $4K+ for even more HP. But I'd LOVE to have a ride with near 200 RWHP on just motor. Only live once!
 

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Discussion Starter #143
Reston
Your right it bumps pressure to 50 psi from the Gen1's 43 psi
 

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? First time I've ever heard about PC3 fuel limitation...
I was having trouble with a barometric sensor fault. The baro sensor checked good so I sent the PC3 back to DJ for checking. Turned out that I was trying to get fuel mixture that threw the baro reading out of the normal range programmed into the ECU. These PC3's (early models used the Baro input to the ECU to modify the fuel tables. The later PC's directly control the fuel injectors. They sent my PC3 back with limits plus & minus that the PC3 could modify the baro sensor output to the ECU.Been a long time ago (2001) but I think it was a plus or minus 10%.
 

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Discussion Starter #145
Update
Been running this setup for close to a month and it's working great.
Came upon an interesting situation the other day while commuting into work. I have the POD 300, PC5, Wideband2 system installed in my 2K BB running a later model ECU 2001 to 2003 USA version. I have a manual switch enabled to turn the autotune function on and off. I set it up this way so that I could record offsets at certain points instead of it contantly correcting . I noticed the other day that my AFR on the POD was dancing up around 14.5 to 15. But only at a certain throttle percentage. So I toggled the autotune on, when I did the POD showed a drop in my AFR. It started dancing around my set point of 13.8. when I switched it back off the number bumped back up to the 14.5, 15 range.
So I messaged Dynojet asking for some insight. They confirmed my suspicions that while in the autotune mode the module in conjunction with the PCV will actively adjust the AFR while enabled on the fly. It also saves and offset during this time to later be able to down load as a permanent offset so that the PCV will make the changes when running on it's own. What this means is that you can use the system in a similar mode to the factory 02 sensor to actively trim your fuel curve as your riding.
So here is an intriguing thought. Build a power map load it as your base tune (say as per dynojet based on 13.8). Then build a cruise offset table (say 14.5 to 14.7) and when your taking a long road trip enable the cruise trim table to actively dial back your fuel consumption.
Hmm EFI is so cool.
 

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Why even bother with two maps? All cruising is less than 20% throttle so I tuned 2, 5 and 10% to run right around 14 A/F, 20% throttle to mid 13’s and 40% up to low 13’s/high 12’s. This give you all-in-one. Great cruising mileage and instant smooth linear acceleration from any throttle position or RPM. BTW, if you tune to 14.5-14.7 A/F for cruising you probably won’t like it. I’ve tried it… It’s ok to do it and it can be done but the throttle gets real digital feeling (while cruising) running that lean. To me it’s annoying. A little extra fuel really smooths cruise throttle sensitivity out. Recommend try to stay around 14 for cruising.
 

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If you guys are stuck with 10% ethanol like we are here in Ky the stoic value is not 14.7/1, it is now 14.2/1 which means that you ideally want to run richer than you would with straight gasoline. I also found that the ethanol % varies from 8% to 13% from station to station which moves the stoic number around. Just my 2c worth.
 

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Discussion Starter #148
Dually noted to both of you
My target right now is 13.8 so I'll leave it there.
What I want folks to come away with is that you can set the tables to 13.8 activate autotune and run in a closed loop mode.
 

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Dually noted to both of you
My target right now is 13.8 so I'll leave it there.
What I want folks to come away with is that you can set the tables to 13.8 activate autotune and run in a closed loop mode.
Duly noted and something I didn't realise. I have not used a PC5 with autotune since my 2012 tuning work on my VFR1200F. Good information beestoys. (y)
 
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