what header do you have on that bitch?

 

greddy 4-2-1 ,1 piece

 

baller, stainless?

 

yes SiR...well its multicolored now

 

You talkin to me? huh? Drama? whatever cuz......

 

Uh huh......

 

Yes you. Jeff. No more drama. Not that I haven't had a little on here but it pales in comparison to your own.

 

No need to get nasty with mpg9999.. he's a friend of mine and he isn't car stupid in the least bit. Let me clear up the differences between CVTC, VTC, and VVL.

CVTC (in Nissan's case), uses an adjustable sprocket with a stepper motor controlled by the ECU. This sprocket can travel a certain amount of degrees in both directions. The ECU is constantly changing the cam sprocket's position to give you low end, midrange, or top end output. Hence the name Continuously Variable Timing Control. This doesn't change the duration of the camshaft or the lift. It simply changes at what point the camshaft's lobes act upon the buckets/rockers to give you the best power output at a given RPM or load. Much like a set of adjustable cam sprockets can move your powerband around.

VTC is the same as above... but is more primative. It uses the same adjustable camshaft sprocket.. but instead of the ECU monitoring the engine and deciding what to move it to in real time.. there is usually a solenoid or servo motor that moves it one direction once you hit a preset RPM until it hits a stopper pin.. and then back again once you get under a preset RPM. The range of travel is set by two stopper pins.... and it's ignorant as to what load is on the motor.. or anything other than a certain RPM point when it is set to engage and disengage.

VVL- Variable Valve Lift- (in Nissan's case) uses 3 cam profiles per set of valves that act on the rocker arm at a given RPM. This happens via oil pressure and is controlled by the ECU or can be manipulated with MSD window switches. The signal is sent from the ECU/window switch, which then opens a solenoid and allows oil pressure to pass and pushes the rocker arm. This allows the next most cam lobe to start working. Depending on which cams you have, they are usually set for different duration and a little more lift. Since this allows more air to get in and more exhaust to get out.. you get more power. I'm not 100% sure about Honda's technology but I'm pretty sure it's closely related to Nissan's.

Hope this clear the confusion up..
Travis

 

I don't have VTEC... I've just got an old school DOHC motor. Nothing special. Mine makes great power
Travis

 

Actually, Nissan's VVL only has two cam lobes per cam (just like Honda/Acura). The difference is that you can activate the intake and the exhaust cam separately. This gives three (useable) stages. 1) Intake and Exhaust on the low cams 2) Intake high cam, exhaust low cam 3) Both intake and exhaust on the high cam. All these people who say VTEC is for gas milage need to be made to drive a super high lift cam in a 4-cylinder engine for a month as a daily driver. The high cams on VVL (Nissans VTEC) would barely idle at 1200rpm and would be a huge PITA for most people. VTEC/VVL makes it possible to get the best of both worlds. Now, if the argument is about whether VTEC is worth the extra money. Only the guy paying the money can really make that choice. Power is not the only factor; some people are content to have just the appearance of speed under their hoods. In the end I would want a VTEC engine over a none VTEC engine for any NA application IF someone else was paying the bill.