OBD conversion - Chipped/Tuned P28

[AFAccord]

You don't need diff maps for different situations. The only time you would need 2 different maps is when you are running a low-boost/high-boost setup.

Just because you have your map tuned for best performance at WOT, which is how any1 would assuming they are paying for dyno time, that does not mean in ANY way that you should have to let go of low rpm driveability. Changing the throttle input thresh hold for VTEC engagement in NO WAY changes the map itself. The only thing that would change is the RPM at which VTEC engages, depending on the position of the gas pedal.

You never lean out the ENTIRE map for gas mileage. When you are on the highway, you are at low load, so your low load map can be tuned for mileage, while the high load area for performance.

BINGO!!

 

[AFAccord]

Hmm. You need to realize that the VTEC you is talking about is e-VTEC, or, the F23 that are ULEV equipped, As in, 3 valves below 2500, 4 above(NOT ALL). When I talk about VTEC, I mean low cam/high cam type, at least on the intake side on F23's so equipped. Not 3-valve/4-valve type.

Which is why I'm saying 2400rpm, not the 4400+rpm on high-cam designs.

F20B= Drivability Profile/Performance Profile. 4200-6500rpm
F23A1/4= Economy profile/Power Profile. 2300-2500rpm

 

[S-spec]

Which is why I'm saying 2400rpm, not the 4400+rpm on high-cam designs.

F20B= Drivability Profile/Performance Profile. 4200-6500rpm
F23A1/4= Economy profile/Power Profile. 2300-2500rpm

Wrong. Not ALL F23's are ULEV. My Original F23A1 is a low cam/high cam design, same as my F20B, but only on the Intake lobe, as with all Honda SOHC VTEC.

 

[AFAccord]

Wrong. Not ALL F23's are ULEV. My Original F23A1 is a low cam/high cam design, same as my F20B, but only on the Intake lobe, as with all Honda SOHC VTEC.

Sir, you are incorrect. Of course all F23's aren't ULEV. I've owned, and tuned both. The ONLY differences between the F23A1 (standard) and F23A4 (EX model ULEV) are the primary O2 sensors (F23A4 is wideband), exhaust manifolds (F23A1 is 4-2-1, F23A4 is 4-1), the design on the VC, and a tighter fuel map in the ECU to meet emissions standards.


F23A1 Camshaft

F23A4 Camshaft

Both number 11 in the illustrations.

Only the F23A5 is different, because it does not have VTEC. For the last time, your F20 has NO RELEVANCE with this discussion!

 

[S-spec]

EDIT:

Alrighty. After all this discussion, I went ahead and made a 2$ VTEC light using an old turn signal from a Civic. AFAccord is 100% right.

Although the stock F23 ECU uses a VTEC window between 2500 and 4000 RPM. Under high load, VTEC engages at 2500. Under low load, the latest VTEC will engage is 4k.

My apologies

 

[NASOHC]

AFAccord is right - The cams on both are identical. My car had an F23A1 not F23A4, all I did was use the long block - everything else is F23A1, sensors, connectors, harness etc. Parts numbers on all mechanical parts are the same. When WebCams did my cam (which changes all OE VTEC lobe grinds anyways) I said it was for an F23A1, not a low emmissions ULEV A4.

S-spec - I still say, changing VTEC setting or threshhold at half throttle will effect full throttle performance on the same map. But i will call bisi today and confirm my theory and yours.

 

[Fuzz]

My car VTec is around 5200rpm... you can hear it with the intake.

Stock Motor - 98 Coupe L4. Same motor as S-Spec, but not blown lol.

 

[AFAccord]

Ok...wow.

I am gonna take a guess here:

- You have owned both, ULEV and nonULEV cars. But have you ever tracked either, on a long sweeping corner, with slightly low oil, only to realize that on the non-ULEV, the classic low-oil pressure VTEC bog occurs at around 5k RPM...

And just for kicks, I went outside my house, took 10 minutes, and pulled out the cam from my scrap F23A1. Here are some pictures:

My scrap motor, under some scrap wood, next to my scrap car.]

Peel away some wood and what do we have?

Notice the 3rd rocker on the intake side? I wonder what thats for. You would have noticed this doing a valve adjustment.
The Cam!!!

2 intake lobes, 2 exhaust lobes, and I see a high lobe, just like my F20. Dunno about you!

/End Conversation. Have a nice day.

What tha heck was all that supposed to prove?

F23A1/4 VTEC is not designed the same as F20B VTEC. I can't think of any more simple way to say that...

NASOHC, I'm really curious what Bisi has to say about a map with an aggressive WOT tune, but mild 'economic' part-throttle tune. Be sure to find out WHY it is or isn't a good idea.

 

[AFAccord]

My car VTec is around 5200rpm... you can hear it with the intake.

Stock Motor - 98 Coupe L4. Same motor as S-Spec, but not blown lol.

Is this a USDM F23? Please explain how you've come to this conclusion, and provide some evidence rather than just throwing stuff in the pot.

 

[Totalimmortal]

My car VTec is around 5200rpm... you can hear it with the intake.

Stock Motor - 98 Coupe L4. Same motor as S-Spec, but not blown lol.

I believe the Canadian Accord had the same motor as ours, no?