Got my egine swaped d16y5 with y8 ECU vtec question.

[Shadowlid]

Ok threw rod bearing in my y8. So i got a y5 to put back in it. Since it was my DD. Gonna rebuilt y8 and put it back in when its built up. Ok my questions is when my vtec kicks in it kicks in at 5600rpm like my y8 but when it kicks in its just crazy and you can fill it pull really hard is this safe since the y5 is not built as good as y8?

 

[AHHVTEC]

do you have any check lights on

 

[Shadowlid]

Nope its all good. Just when vtec kicks in its crazy how it works it like jerks forward it kicks in so hard?

 

[AHHVTEC]

well the smoother the better actually but unless you got a check light on i wouldn't worry about it. the way most vtec works is there is a torque drop right before vtec and the a torque increase at the point of engagement making it feel like its jerking forward.

 

[tabKola]

You feel it because vtec on a Y5 is supposed to kick in at 3000 rpm because it is vtec-e.

 

[K2e2vin]

Your motor is pretty much running like crap in "low-cam"(which is really only 1-intake valve opening) so when it switches to the high-cam at a higher RPM, there's a very noticeable difference.

The motor is obviously not running optimally, not sure how it'll affect reliability/engine life but definitely try to swap in a Y5 ECU ASAP(chances are the Y5 is running very rich with the Y8 ECU).