Ok, i just got done swapping a gsr motor into my eg setup is as follows:

99 gsr long block
92-95 jdm b16 sirII trans
stock p72 ecu
apexi world sport exhaust with oem cat

After driving the car a bit i am not sure vtec is engaging. in all the other vtec cars i have owned and ridden in vtec makes a distinguishable noise when it engages. the only other gsr i have ridden in was my swapped crx but that had a skunk2 intake mani. i was wondering if the butterflies in the stock gsr manifold make it harder to hear vtec. and also, is there any ways that vtec is not working even though i have no cels?

thanks in advance

 

you may just have a bad vtec solenoid. Or the butter flys aren't opening or even the fact that oil level is low will cause vtec not to work. Let me know

 

check your solenoid, and like the other guy said, it may be low oil, oil pressure is what allows your vtec to engage, check your wiring also, thats what happend to me.

 

even with mods, the vtec is going to be a quiet transition. now if you cant hear the butterfly valve opening, then you might have a problem. open up your intake box and see if you can hear it.

 

is there a way to test if the butterflies are opening"?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by FastAsleep &raquo;</TD></TR><TR><TD CLASS="quote">is there a way to test if the butterflies are opening"?</TD></TR></TABLE>

VTEC will engage at ~4400 RPM and the IAB (butterflies) will open at ~5600 RPM. You will not really here the 4400 RPM VTEC with the stock intake manifold. If the engine and ECU are USDM, you will get a CEL if the VTEC does not engage when it is signalled. If the car can get to the redline with any sort of power, the system is most likely working well.

The IAB operation can be observed at startup. The butterflies are normally open. When you start the car, they should close when vacuum is applied. You can watch the linkage move on the driver's side. The engagement at 5600 RPM is audible. If the butterflies are closing but not reopening, check the wiring for continuity and check the release filter on the IAB solenoid.

 

good info man thanks. i'll check out my butterflies..