or with turbo preludes....

do anyone of you have problems with VTEC? datalog says that VTEC engages and i can also hear it. but i don't feel it pull and actually feel it decrease in power.

my theory says that the oil feedline to the turbo is tapped from the wrong place. i tapped it from the oil pressure sensor off the back of the block which is under the oil filter (these are the directions i got with the turbo installation manual). i guess this is robbing oil pressure thus preventing VTEC from mechanically turning on? there's sandwich thing i can buy that goes between the block and the oil filter. a port is connected to it where i can attach a oil line. i think it's by Golden Eagle. did you guys get this? or is it supposed to work, with more tuning?

i guess i'm curious to know if any of you guys got VTEC to work after tapping oil from the oil pressure sensor.

thanks!

 

Vtec whats vtec?
I cant really feel it on mine, it's a pretty smooth transition.

 

Weird. I have sohc vtec (intake only), and it makes a surprising difference. You can hear it through the intake, as well as feel the surge of power.

I also have my turbo tapped to the oil pressure sensor port. I really doubt your turbo feed line is sapping that much pressure from the sensor location, unless it's attached in some strange fashion. On mine the sensor attaches to a brass T on a short line to the port, and the 90 degree bend portion of the T runs to the turbo. That way, pressure still has a straight shot at the sensor. Also, when VTEC engages, your motor is spinning at high revs, and the oil pump should be generating more than enough pressure to kick VTEC. An easy test would be to attach an electronic oil pressure guage and see what it says, since it gets it's readings from the sensor.

 

the strange thing is that i can hear the VTEC, which means something mechanical is happening. but the power is crap. i guess it's more of a fuel/iginition thing, huh?

i also have the oil tapped from the sensor. it T's off it and goes to the turbo. from the bottom of the turbo, it just empties out to the oil pan with a .5" diameter tube approx. 6" long.

anyone else with a turbo that tapped oil from the pressure sensor switch?

by the way, this is a 2000 prelude with an H22A motor, stock internals at 6psi (if that helps)

thanks for all the inputs, guys!!!

 

anyone?

 

That's my motor and my setup. Well, I would first ask what fuel managment are you using. You may be running very rich at the initial VTEC engagement and your engine it just bogging down.

Your oil feed is in the right place, it won't make a difference if it's done right.

 

i have a programable ECU.

the AEM EMS

 

well i know i had this prob already with the Hondata. If its kicking into the Hi speed maps. Vtec is engaged. You might not be able to feel it or hear it , but it should be engaged.

I have feed line tapped from where the stock oil pressure sensor is. Mine works fine.

 

If it's tuned well, high map transition will be smooth.

 

hmmm.....

before the AEM EMS installation....i only had a secondary fuel pump, FMU, and stock injectors with the stock ECU....the VTEC didn't feel like it activated correctly but it did sound louder at the ~5500 mark like it was activated

after the AEM EMS i'm still having the same problem. the EMS doesn't have a seperate map for VTEC. only an option setting. some people said that they used to nitrous map as a VTEC, but didn't find it benefical and the original options allowed to set VTEC we sufficient.

 

any ideas?

 

bump

 

anyone else with this problem?

 

its probably in your tune. how does your ignition curve look?

 

a bit retarded (pun intended)

i'm comparing it to another turbo prelude's map and mine's a bit high....but i guess i'll just do it till i hear knocking

 

what timing are u currently running at what psi?

 

friend had the same problem with the EMS, but he had some crazy nitirous cams, after alot of headache, and alot of time adjusting the cam gears, we yanked them and put the stocks back in.. man it made a difference, the lower end is pokeyier, but the top end is much better, our guess was just way to much over lap for a FI application, that worked awesome with nitrous.. but, since ur using the stock cams, my guess is that maybe ur ignition maps aren't right..

 

what timing? meaning.....

i'm running at 6psi

 

what is your ignition timing value at 6 psi?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Cowboy &raquo;</TD></TR><TR><TD CLASS="quote">what timing? meaning.....

i'm running at 6psi</TD></TR></TABLE>

The tune is the blame...i'll bet a mooses eye ***** on it.

 

i guess i'll advance the timing...

do you guys use the knock sensor to do advancing or is there another way?

thanks guys!


Modified by Cowboy at 5:10 PM 3/24/2004

 

ideas or experiences from anyone else?