imzjustplayin

I was wondering if anybody knew what kind of HP the Civic VX has when the Vtec-E doesn't engage into the higher RPM range, giving it its rated 92hp. The Civic CX and the CRX HF have 70hp and 56hp respectively, and the Geo metro are in the range of 50-70Hp as well and they all get good mileage. So what I wanted to know is if the Cam Profile for Vtec-E off is more conservative and works better in the low RPM range than the CX or HF cam profiles or not. I'd have to imagine that it would be the case because the HF and CX have to be able to function somewhat at the higher RPMs while the VX does not (at least that cam profile when Vtec-E is not engaged).

Ya Digg

hmm, I think the vtec-e cam would be less agressive out ot vtec because it still has 3 valves per cylinder to make some power where the cx has 2 valves. Just a guess.

krysted9354

all i now is when i had my vx stock i was getting 56 miles to the gallon, and vtec-e in engaged underload ,menaing not at sertain rom, so vtec can engage at 2,500 or 5,000 , depending on air/fule frlow and bunch of other ****, THATS ONLY WITH civic vx D15Z1 .

imzjustplayin

Are you saying that if you rev the engine when it's not in gear (i.e little to no load) that vtec-e won't engage? Also I read that the vtec-e only engages at like 2000-2500 rpm.

krysted9354

yes, and u read wrong, under normal to mild driviving it 2,000-3,000, if u gun it its
2,000-,2,000 , if ur cruising exampole highway then 4,500-5,000.



all depends on driving, conditions, everything theres no explenation inless u have driven one.

94EG8

Power output should be lower. Vtec-e is kind of weird. in Vtec-e the engine operates with 1 intake valve per cylinder almost completely closed to create a votex in the combustion chamber, effectively running the engine in 12 valve mode, it does this up until about 2500RPM where it switches over to standard 16 valve operation. Heres whats really weird, unlike normal SOHC vtec where power goes to the vtec solenoid to engage vtec, the D15Z1 disengages vtec-e when power is applied to the solenoid, sooo if you don't hook up the vtec solenoid it should be running in 12 valve mode all the time.

krysted9354

YUP, and thats controlled by the ecu the spool valve is same as the d16z6 .

imzjustplayin

This doesn't make any sense, I think you need to reword it or get your facts straight. On a vtec E and Vtec engines, they're running off of the cam's default profile, once vtec is enabled, then it multiplies what can be read off of the cam so that it's effectively more aggressive. On Vtec-E, it goes from slightly opening one of the intake valves to opening it to the equivalent of opening the other intake valve when its not in vtec mode and the other valve just opens more aggressively. Basically vtec-e is suppose to make it the equivalent of a Vtec engine when Vtec isn't engaged (16 valves, non aggressive vs. 16 valves aggressive).

Vtec E: 12 Valves, 16 Valves non aggressive (one valve IS always more aggressive than the other)
Vtec: 16 valves, 16 Valves aggressive, (equally aggressive I believe)


That IS what I know, what I don't know is how many variables effect it engaging or not. Should I assume that if you're cruising on the highway and you accelerate at a moderate speed from 60mph to 90mph, that vtec (performance/16valve mode) possibly will never engage despite being in the 5000+rpm range?

94EG8

Huh???

robfrmny21

they do this cuz when you remove or add a ground what ever circuit is being operated turns on or off faster then if you were taking the power away.

This is how fuel injectors work as well