seanv98

Hey guys I was just wondering as to why there is a slight drop in power after VTEC engagement? I can only notice an increase when in kicks in, but when you see a dyno graph there is usually a slight dip in power right after engagement. Cheers

MPR

It's not easy to tune an engine when suddenly the cams get big and you have considerably more air rushing in and out of the engine. The ignition timing and fuel injectors have to adjust instantly to compensate. It's very tricky to tune it and smooth out the transition. The guys at honda have done a pretty good job with the stock B series engines.

seanv98

That makes sense, the crossover happens so quick. Cheers, thanx

zeeman

iTrader: (1)

if theres a dip in the power that can be from vtec engaging too low, or not enough fuel/timing right when it switches over to the vtec lobes.

seanv98

When you tune ECU's for people do you make the VTEC cross over seemless? Do you tune on a dyno? I hoping to have my motor tuned later this summer.

zeeman

iTrader: (1)

the only way to make it "seamless" is to tune it on the dyno. This is b/c the only way to measure the power output and see the whp and torque curves is by using a dyno.
But typically yes, when dyno tuning cars i try to get as smooth as a vtec engagement as possible, some cars just jump 10-15whp in vtec no matter what you do though.

seanv98

Thanx alot Zeeman. What do you use to tune cars? (crome, neptune ...etc) do your customers just need to bring the car the money and a few beers?

bbarbulo

iTrader: (2)

zeeman just uses his magic

seanv98

haha, he realy does know his ****, and has been a great deal of help on many occasions.

zeeman

iTrader: (1)

I use crome and Neptune, but prefer Neptune.

I don't drink beer, i'm allergic, so don't bring any for me...lol.

seanv98

Allergic to beer lol. Cool thanks for the help guys.

zeeman

iTrader: (1)

allergic to ALL alcohol, it sucks, but its true.