Vtec question (not noob question, lol)

[mugen_ctr]

Ok, well iev been thinking lately why is vtec considered so great, and why so many fan boys love it...
Now as far as i know, vtec is basically two different cam profiles set up, and to which changes from one profile to another according to oil pressure or electronic, enabling better fuel econmy down low and higher power top end, yes its a good idea, an proven to work

BUT, my question is, to those who have built B16/B18/B20 vtec heads, do u still retain the vtec system?

Iev seen the power curve on a dyno, to me, its not such a great power band, not a liner power band compared to other n/a motors, my theory behind it pretty much lies in racing cars, hence why they dont use it or have similar system, having a liner power band can pretty much pull u out of most situation, tight corners, high speed runs etc etc

[curtis265]

As far as i know, it would make sense to elimintate vtec altogether - run high cams permanently.

Honda had a very clever idea with vtec, i suppose that's why fanboys love it so much.

[EKVTIR-T]

Its the nature of the beast

A high output high revving small cc motor isnt going to have a linear curve

And yes some of the fanboyism is over the top but Honda do deserve respect for creating a great line of engines..

Just need to see the big picture and that others companies can do it too,such as the mivec vvtl and the likes

For dedicated track cars one could argue why retain vtec at all..case in point vtec killer camshafts

[GSi_PSi]

many ppl who bag out vtec most probly never experienced the motors for themselves,

[wynode]

The primary benefit of VTEC is that it allows you to have a 'lumpy' cam while not sacrificing low rpm performance. Honda have made it popular because they mass produced it in a very reliable form.

If you however only had the equivalent of the lumpy cam, then low RPM drive ability would suffer. As for the non-linearity in power delivery, this is because most manufacturers to date have only implemented a 2-stage lift cam (there is one 3 stage lift cam from memory but it didn't gain much popularity). If it was possible to continually vary lift then that would help linearise the power delivery.

Most manufacturers now implement continuously variable cam timing.

But looks like your question is "who have built B16/B18/B20 vtec heads, do u still retain the vtec system" ?

[dougie_504]

Sensational engineering. Good fuel consumption down low, and power up high when/where you need it. The best of both worlds for a 4 cylinder engine IMO.

Oh, and it sounds hectik in tunnels yo...

[T-onedc2]

The primary benefit of VTEC is that it allows you to have a 'lumpy' cam while not sacrificing low rpm performance. Honda have made it popular because they mass produced it in a very reliable form.

If you however only had the equivalent of the lumpy cam, then low RPM drive ability would suffer. As for the non-linearity in power delivery, this is because most manufacturers to date have only implemented a 2-stage lift cam (there is one 3 stage lift cam from memory but it didn't gain much popularity). If it was possible to continually vary lift then that would help linearise the power delivery.

Most manufacturers now implement continuously variable cam timing.

But looks like your question is "who have built B16/B18/B20 vtec heads, do u still retain the vtec system" ?

^^^What he said^^^
plus, on track a small engine runs gear ratios to suit the high rpm power band, therefore not spending time at low rpm which would otherwise require the advantage that vtec brings. Too many people don't realise that (performance oriented B & K series etc) vtec was created to make a "race-like" engine drivable in low rpm, not to give a shopping trolley engine a "boost" which "kicks in yo"