Vafc 2
#21
Registered User
Originally posted by gernby
The time and money is most significant at the dyno when you tune it.
The time and money is most significant at the dyno when you tune it.
What occurs or is the reason to dyno?
What occurs there and where should I look to find a shop to do it/who would Dyno it typically?
What is tuned when you dyno?
How much does a dyno usually run?
Please don't flame me - I've seen the term dyno thrown around a lot and have an idea of what it means but I'd like to get all the info on it
#22
A dynometer is needed to measure HP at the rear wheels as you adjust the air / fuel ratio throughout the RPM range. Stock engines run more fuel than is optimum for maximum power, so the V-AFC is used to remove some of this extra fuel. It may seem odd that less fuel gives more power, but the closer you get to "optimum" the better. The dyno also needs a wideband O2 sensor to make sure you don't go too lean in your tuning which could result in engine damage. Any speed shop with a dyno (and wideband O2 sensor) should have experience tuning V-AFCs.
#24
VTEC explanation:
Most cars don't rev much past 7k because their cams are set to deliver peak power at a lower more usable RPM and drops off as you climb up the tacho.
Race cars generally run at much higher rev and are tuned to produce power at these higher ranges. As a result they don't produce much power down low (that's why F cars use so many revs leaving the pits. If they don't it stalls.).
No imagine if you could drive your car along like any road car, but as you got to peak power (for that cam), you could jump out, swap the cam for one out of Schuey's Ferrari, jump back in and keep going up through the new range.
That's effectively what VTEC does. It engages a much more aggressive cam profile at 6000rpm and turns your car into a totally different beast.
BTW, all my experience with changing the VTEC engagement point on the S has lead me to believe Honda got it spot on.
Most cars don't rev much past 7k because their cams are set to deliver peak power at a lower more usable RPM and drops off as you climb up the tacho.
Race cars generally run at much higher rev and are tuned to produce power at these higher ranges. As a result they don't produce much power down low (that's why F cars use so many revs leaving the pits. If they don't it stalls.).
No imagine if you could drive your car along like any road car, but as you got to peak power (for that cam), you could jump out, swap the cam for one out of Schuey's Ferrari, jump back in and keep going up through the new range.
That's effectively what VTEC does. It engages a much more aggressive cam profile at 6000rpm and turns your car into a totally different beast.
BTW, all my experience with changing the VTEC engagement point on the S has lead me to believe Honda got it spot on.
#25
Oh, and the plug and play harness from the original V-AFC should work fine (assuming they haven't swapped any pins). I expect the knock sensor connections are on the other little plug behind the main one in the picture.
#27
FOR! It's a cool item that gives you some nice control over your tuning.
And if you've got some mods it's the only real way of taking advantage of them short of an AEM or e-manage.
I'll be reinstalling mine tomorrow and should be off to the dyno next week. Got a track day on the 30th.
And if you've got some mods it's the only real way of taking advantage of them short of an AEM or e-manage.
I'll be reinstalling mine tomorrow and should be off to the dyno next week. Got a track day on the 30th.
#30
Registered User
Thread Starter
Join Date: Jul 2002
Location: franklin sqaure, NY
Posts: 1,110
Likes: 0
Received 0 Likes
on
0 Posts
hey i just got done installing my vafc2, im gonna try to get it dyno tuned this week, if not next week, ill post dyno sheets and pictures of where i mounted it, wasnt to hard to install, should have done it quicker but at the same time i was doing that, i was tryin to help my friend wit his 350z to put his exhaust system on, but i'd say its about a 1 and half hour to 2 hour job, if anyone needs help installing, or questions about any of the colors of the wires, please feel free to ask
i dont think it would work with the orignal vafc harness because there are a couple of more wires............
i dont think it would work with the orignal vafc harness because there are a couple of more wires............