Lowering VTEC
#65
it was just a question man. with my experience working on Hondas Vtec, no i don't see anything wrong with it but figure id ask to see if someone knew something i didn't
#69
In this case, all you are doing is changing the stock valve profile to come in earlier in the rpm range, the motor isnt now magically revving higher because vtec just kicked in. You are simply tuning the engine mechanically, just like if you were to replace a cam in a motor, in the case of our motor we have two different profiles and an engine that is capable of operating the more aggressive profile efficiently at a lower rpm then how Honda set it up, given a few small changes on our end. As long as the car has the proper fuel and ignition timing to run proper for the cam in the new lower operating range, there won’t be any detriment to the engine.
Fortunately in the case of the stock timing advance on our ecu, when you lower vtec, the engine wants more timing not less, so without any timing corrections the engine is running a more conservative timing tune between the new lowered vtec rpm and the stock, so no detriment there. Proper fuel is what becomes the primary issue, as it needs more fuel to run in vtec then the primary cam, and depending on the MY and other breathing aftermarket parts this may or may not have to be addressed.