if you calculate the % change in gear ratio for each shift, then an AP2 drops out of VTEC on both the 1-2 and 2-3 shifts, assuming a VTEC transition at 6k.

% RPM
1st gear 3.133 -- --
2nd gear 2.045 0.653 5222
3rd gear 1.481 0.724 5794
4th gear 1.161 0.784 6271
5th gear 0.942 0.811 6491
6th gear 0.763 0.810 6480

Edit: Gear ratios are from Honda's website

Example: the 1-2 shift drops the RPM by the ratio 2.045/3.133 = 0.653. That means an 8000 rpm shift will drop to 8000*0.653 = 5222 rpm. So you end up feeling a sag on that shift until the engine again reaches VTEC.

 

Yet another example of AP1 superiority

 

i dont know about you but my ap2 does not drop to 5222 rpms after my 1-2 shift, nor does it on the 2-3 shift. My ap2 is 100% stock.

when i shift from 1st to 2nd it is still in vtec

in fact from the looks of it that entire calcuation is wrong.

 

The only time I noticed this is in an AP2 with a toda flywheel. If you are not spot on with your shifts, it will fall out of vtec.

 

yea I dont even take it all the way to 9k most of the time and I am still in vtec when I enter the next gear.

 

Thanks for the input, Billman. My calculations are exact only if there is no clutch slip in the shift. So the lighter Toda flywheel would show the effect. Also, we have to factor in the infamous CDV. The engine may stay at or near VTEC, but it is at the expense of clutch slip.

GrandMaster Khan; "in fact from the looks of it that entire calcuation is wrong." If you have an alternative calculation to offer -- post away. I'm interested.

 

 

your calculations seem to be about 1000rpms off give or take a few 100 rpms.

did you take into account the different final drive of the ap2 vs the ap1 in your calculations?

My ap2

2nd 6200 rpm
3rd is about 6600rpms

i cannot remember exactly since i dont take notes while driving briskly

 

Furthermore, redline is really at 8200 I am told.

 

I do not fall out of VTEC during my WOT shifts. Honda would not design a car this way.