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vtec setting for k20a2
Posted: Fri Aug 09, 2013 5:20 pm
by gunja1
Hi yall,
I have the stock map for the rsx type-s but I want to set the vtec lower like :
lower boundary = 4600 rpm @ ??? kpa
upper boundary = 4800 rpm @ ??? kpa
I don't want to broke somethin' then I want to know wath kpa should be the best for lower and upper boundary ?
ps : I have sri aem
Re: vtec setting for k20a2
Posted: Mon Aug 12, 2013 9:43 am
by Spunkster
Re: vtec setting for k20a2
Posted: Mon Aug 12, 2013 7:24 pm
by gunja1
I have already read but I don't understand...
It's kind of hard to understand this when you are a beginner. It's the manifold pressure that I don't understand.
Little help would be very appreciated.
Thanks
Re: vtec setting for k20a2
Posted: Tue Aug 13, 2013 10:55 am
by LK7R
gunja1 wrote:It's the manifold pressure that I don't understand.
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Manifold vacuum, or engine vacuum in an internal combustion engine is the difference in air pressure between the engine's intake manifold and Earth's atmosphere. (Wikipedia)
The rest is self explaining in the help file, which is under link that Spunkster gave you.
This is basicaly answer to your question:
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The above screen shot shows VTEC switching at 5000 rpm when the manifold pressure is 89 kPa or above (which is close to full throttle), reducing in a linear fashion to 5800 rpm at 25 kPa manifold pressure.
You want to have Lower Boundary set to around 80-96 kPa (you want VTEC engaged early when trying to accelerate hard). That way VTEC engages as soon as Lower Boundary rpm and maifold pressure are met.
The Upper Boundary is basicaly the latest point where you want to engage VTEC if you driving on highway with part throtle. You want to set it to 30-60 kPa.
Do your homework and test it out on the road, you can't damage anything if you follow guidelines in the help file (VTEC Lower Boundary higher than 2000rpm and Upper Boundary lower than 6500rpm).
Dan
Re: vtec setting for k20a2
Posted: Tue Aug 13, 2013 10:40 pm
by gunja1
Then,
Lower boundary : 4600 @ 90 kpa
and
Upper boundary :4800 @ 30 kpa
should be alright ?
Re: vtec setting for k20a2
Posted: Wed Aug 14, 2013 1:18 am
by LK7R
gunja1 wrote:Then,
Lower boundary : 4600 @ 90 kpa
and
Upper boundary :4800 @ 30 kpa
should be alright ?
What you are missing here is the point of the VTEC window.
For cruising you want VTEC to engage high (fuel economy) for example at 6000rpm.
For power as soon as High Cam produces best torque (this is different for each engine, could be 4600 rpm in your case, this has to be determined on dyno or "so so" via road tune).
Re: vtec setting for k20a2
Posted: Wed Aug 14, 2013 2:19 pm
by gunja1
When I bought the car, it was set like this :
Lower boundary : 4600 @ 89 kpa
Upper boundary 5800 @ 25 kpa
BUT, the vtec doesn't kick one shot. At 4600 rpm it sounds like timid and gradually at 5800 rpm it sounds like aggressive.
I want that the vtec sounds like in the stock vtec setting (aggressive one shot) but lower like 4600 rpm.
Anyway, when crussing on the highway, I don't exceeds 3500 rpm
Re: vtec setting for k20a2
Posted: Wed Aug 14, 2013 2:38 pm
by LK7R
I am sorry, but you have to learn a bit more about how the K20 works. Have a look at tech section on hondata website.
To answer your question:
Sound of engine after vtec engaged is dependent on VTC angle. So in order to have the "the same VTEC with sound" as before, then you have to have set both boundaries to 4600 and 0 kPa. Also cam angle must be set to the same value as in the map before. That will give you the same sound, but it won't work better but most likely even worse.
Simply put, there is no quick and dirty way to learn how to tune ECU without days and days of study, testing, hands on experience and money for dyno time.
Dan
Re: vtec setting for k20a2
Posted: Wed Aug 14, 2013 4:08 pm
by gunja1
Yes, I have. I have other questions but you should be bored to answer to my stupid question.
By the way, thanks a lot for all the answers.
Re: vtec setting for k20a2
Posted: Wed Aug 14, 2013 11:12 pm
by LK7R
gunja1 wrote:I have other questions but you should be bored to answer to my stupid question.
Everyone started somehow. It is not like we do not want to give you the answer, but to start giving you good answers that will quicky resolve your problem, you have to study a bit more (at least you have to master everything in the training videos and help file). You will see that most of "stupid questions" will disapear and you will have just "clarification questions" (like: I have done this and that, help file states this, i did it and it is not doing my thing, here is log and cal...).
gunja1 wrote:By the way, thanks a lot for all the answers.
No problem. Have fun with tuning your vehicle.
Dan