B16B safe Vtec engagement point?


ManosEK9 said:
Obviously there's something wrong here......:nerv: If you are 100% sure is a B16A2 it means that your actual redline is 8000 rpm, the clock is not an SiR clock and it doesn't say the truth for the redline, i.e. you are overreving your engine(don't ignore this).......On the other hand however, in case is a B16B and you are not aware of(you wish :p), it means the redline is true and your vtec was dropped to 5800 rpm from 6200. Is just one of the two, it cannot be both! :nice:
Click to expand...

every b16a iv had or been in has redlined at 8500rpm its defo over 8000 anyway so im away to look into this one find out more about it
 
ek4 vtec come in at 5500! :) and cuts out at 8400
ek9 vtec comes in at 6000-6100 and cuts out at 8800
 
omg all this talk about vtec and redline, unless you hook up a digital tach to your car you have no idea, something like apexi afc neo, vafc or a stewart warner digital tach gauge.
 
I agree with all those who said stock setting is best.

The bigger the capacity of the engine, the lower you can set the vtec point. Making power is all got to do with the Volumetric Efficiency(VE) @ xxxxrpm.

B16B's VE for the high cam is above 6000rpm for the stock engine. I would set mine any lower than 5800rpm, I feel a loss in power, and dyno shows a dip in power.

B18C is good for 5500rpm lowest.

B20 probally 5000rpm

K20A is a different story. Because of VTC, the VE is great at all rpms. Tuning this engine is very difficult. hondatech.com.au has dropped the vtec on the FN2 CTR down to 3000rpm with tuning and it still made more power. VE was amazing on those engines.
 
I'm running an EM1 civic (B16A2) and the vtec engages at 5500 and redline is at 8000rpm on the cluster.

trep
 
strange, im in a b16a2 and mine comes in at 5500 and does cut out around 8400ish, also, is it possible to damage your engine if kept in vtec for too long
 
I think people may be getting the B16a and B16a2 a little confused.

I also had a B16a2 and can tell you now that it revved past 8000!

But that is besides the point.

For best VTEC engagement point is going to be different from car to car and driver to driver.

Look at how you drive and what you want from your car.

Look at the modifications you have also and what modifications could help achieve what you want.

If you want more top end speed, then have a later VTEC engagement and chose modifications to help raise the top end speed.

If you want low down power & quick acceleration, lower the VTEC engagement point and add mods to help in that area, such as a 4.9 final drive and lightened flywheel etc...

But if you just want to know how low you can set the VTEC engagement point, truth I guess is anywhere!

You can set it at 1000 rpm if you wish, but it isn't going to achieve anything.

And that is not to say it will even kick in.

If the oil pressure isn't sufficient enough, then VTEC will not engage.
 
i habe a b16a2 ek4 and vtec kicks in at 5400 ish and limits at 8500ish final
 
The best way to determine the vtec engagement point regardless if its B16,B18,B20 is to fit an aftermarket vtec controller.Run the car on a dyno without engaging vtec at all.Go right up to the limiter.Then engage vtec as early as you can and run the car up to the limiter again.If you compare the two torque curves of the two seperate runs you will find that with out vtec the torque starts dropping off anywhere from 4500rpm and up depending on the engine you have.On the second graph you will see the opposite happening.There will be little torque up to a point and then the curve will intersect the first curve and start climbing.This intersection point is where vtec should engage.
 
The reason why alot of people dont like doing this is because it feels like vtec doesnt kick in as hard.There's a reason for this.What happens with the stock engagement point is that the vtec engages so late that by the time it does your torque curve has started going down hill rapidly,then vtec engages and gives you a kick in the kidneys.Sure this feels nice but in actual fact for those 1000rpm's that your torque curve is heading down you're losing acceleration.When setting the vtec at a lower rpm,the car "feels" slower but when you look at the dyno graph you will have a larger area under the torque curve and thats ultimately what overall power is.
 
The standard vtec point set by Honda is too high. This is done for marketing.

If Honda set it at the optimum position, you wouldn't feel the "vtec kick" and that would have lost them 50% of their sales.

The only way to determine the optimum vtec point is doing 2 seperate dyno runs, as 1926vtec explained above.

The best vtec point is where you don't feel the transition to the high-cam. Smooth torque curve = more power = better acceleration.

And no, changing vtec point doesn't affect your top speed (unless you were to set it above your rev limit, thus effectively only running on low/mid cam upto redline) :)
 
You must log in or register to reply here.
Back
Top