InfiniteVTec

This thing suprises me it's pretty damn accurate to previous dynos I've done. I've done few mods since the dyno... which include GSR TB, P/S Pulley, and Alternator Pulley... I also dropped the vtec engagement RPM to 5,400 after the dyno, which was at the stock level i believe. It seems to flatten out power as it's increasing then it drops torque/hp then begins increasing from 5,650 RPM.

I'll be trying the vtec engagement at 5,600rpm and 5,700rpm. I made this forum to give you guys a 1st hand experience of it works or not. The only downfall about this item... finding a location to test it.

cvchtchbck92

In regards to your vtec engagement. Why is it so late? At least compared to mine that is. I just bought my GSR from hmotorsonline and my vtec engages around 4,500 rpm. I haven't dyno'd it or anything so I don't know how the curve looks.

Omniscient

Because he has a D series motor.

qtiger

Also, modified cars typically work best with higher than stock VTEC engagement.

Omniscient

Oh I read that wrong. I thought he was asking why his GSR engagement point was different that that other guys with the G-Tech.

InfiniteVTec

I lose power lowering the vtec engagement so hp and tq don't pick up til around 5,600-5,700 which I think is the stock level. It has something to do with airflow velocity related to engine speed and the high cam profile.

I guess in theory if the engine rotating too slow the high cam loses its efficiency as air is not entering the chambers quick enough.

Too late of a vtec engagement wouldn't take advantage of the high airflow velocity that occurs at high RPM.

BTW I'm becoming unsatisfied with the GTECH RR results lately... i been getting bogus readings lately.

westcoaststyle

Cool. My VTEC was set at 5200 based on dyno results and testing.

InfiniteVTec

What engine and cam(s)?

InfiniteVTec

Personally I think boosted applications do best with a lower vtec engagement and N/A with a stock or higher engagement.

Provocateur

The correct engagement is when the low cam torque equals the high cam torque. It doesn't matter if it is boosted or not. In theory, the point where the torque numbers are equal is the correct vtec engagment for best overall power and it should be felt by the driver as a smooth transition.