The info below is the ONLY thing ive been able to find. if you put it on paper (assuming the crank angles are in the same order as the valve names) its really weird looking. from the ridiculous amount of research ive been doing lately on the four stroke cycle the primary intake seems off, in most engines the intake valve opens before TDC to create valve overlap, and this didn't seem right, I know Honda is smart enough to utilize scavenging for better efficiency. Another thing i don't understand is what "Both intake exhaust" means?
id just like to know if anyone can figure out what angle each valve opens and closes at. (preferably with vtec engaged)

Honda F engine - Wikipedia, the free encyclopedia

Valve Operation[edit]
Low-Speed Operation High-Speed Operation All Conditions
Primary Intake Valve Secondary Intake Valve Both Intake Exhaust Exhaust Valve
Valve Opens 24* ATDC 26* ATDC 0*TDC 30* BBBC
Valve Closes 23* ABDC 76* BBDC 36* ABDC 15* BTDC
Lift 7.0mm 1.8mm 10.0mm 9.0mm

 

If you want to learn how Honda's system works for the F23, go to the sticky above in this General Tech Help section, "Common DIY and Other Info. Threads" and download the 94 Accord service manual. This service manual has info. that the 6th generation Accord service manual (1998-2002) didn't include. It has a description of the VTEC system on the F22B1 engine, which will give you more insight.

Then search the internet under Honda VTEC to tie the info. together (it will make more sense that way); there is a wealth of info. out there once you do that (e.g., video, literature, etc.). -- Sometimes, you have to start a little further back with some of the history to learn how a system works.

 

Thanks for the info, but i already know how vtec works, its not exactly complicated, but i just need somewhere to find the exact specs for this specific engine when each valve opens and closes.

 

Wild guess: There are some typo's in Wikipedia's table. I think they pulled the table from: Honda Accord -- Drivetrain. The table on this page is easier to read. I'm no engineer but I think there may be a couple of things wrong with the table.

• "Both Intake Exhaust" should read "Both Intake Valves"
• "BBBC" should be "BBDC"

Re: valve overlap. What's best for power efficiency can conflict with what's best for fuel efficiency and emissions efficiency. There's a PDF called THE IMPACT OF VALVE EVENTS UPON ENGINE PERFORMANCE AND EMISSIONS that explains the trade offs.