Originally Posted by Blue_TC_Man

the l in the vvtl-i code does not mean lift is how the engine is run, the lift refers to a process where the valve is lifted higher causeing a sudden increase in power, in a vvtl-i engine lift kicks in a 6k rpm, all engines run off lift if you dont think they do take out your cams and allow the car to have no valve lift and see what happens

Originally Posted by 1tc4u2nv

^^ you, my friend are a stubborn and uninteligent man, all you have to do is look it up..........
http://www.toyotacelicas.com/information/faq.html
is the fifth one down.

Originally Posted by TCpete

ok im half plastered from drinking and partying last night from new years so im gonna tackle this on half a brain...and to shut you noobs up...

FIRST EXPLAINING VTEC:

video on vtec : http://videos.streetfire.net/video/3...E74118BB4A.htm

VTEC works with cams shafts that have 2 different profiles a soft profile and a harsher profile...for daily driving and fuel economy ur driving on the softer profile until you hit about 5k-5500k rpms (depending on which vtec motor in which the vtec solenoid locks the rockers to now slide over to the harsher side creating VTEC in which now the car uses more power created by the harsher cam that has a lumpier duration to create more lift in the valves intake and exhuast making more power. VTEC motors run on lift and timing because there is no science and no ecu controlling at which point it deems it necessary to cross over to produce the power.. it is a steady punch and 1 time in the rpm range.

If u think of it this way say u have a camaro with a 350 v8, it comes with a certain cam that is designed for everyday driving and fuel economy. Now put a big choppy cam in it which gives u an incredible top end increase but u have a rough idle and ur low end power is dead untill u reach the cam's operating rpm. Vtec combines the 2 cams maximizing the whole powerband and allowing u to have a smooth running fuel efficient 4 cylinder for everyday commuting but when u want to play you have the power on demand.


also TOYOTA HAS 2 VERSIONS OF VVT-I TECHNOLOGY DUMBASSES

vvti = variable valve timing inteligence
vvtl-i = variable valve timing lift inteligence


Now with vvti all this does is change the duration of which the valves open. VVTI adjusts the amount of valve overlap there is. Valve overlap when BOTH the intake and exhaust valve is open at the same time. This between the exhaust and intake stroke. For an engine to make more power and be more efficient you want to bring the most air in and out as fast as possible. This is possible by keeping the intake valve open longer and opening the exhaust valve earlier. During high RPM conditions more valve overlap is better. However too much valve overlap can cause the air to enter the wrong port, as you can imagine when you have both valve open at the same time. At high RPMs the intake velocity will not allow the exhaust to enter the intake port. But during low rpms less overlap is better because there is less intake velocity. It works by using hydraulic pressure to adjust either the cam gear or the gear driving the timing chain (im not sure which one) So to sum it up VVTI controls valve overlap to make it more efficient meaning more low end torque and more high end power.

VVTI DOES NOT KICK IN AT A CERTAIN POINT LIKE VTEC R AT 6K RPMS IF U THINK THAT UR AN IDIOT....it continuously modifies the timing throughtout the powerband to compensate for driving conditions!! yes at around 4k rpms the motor comes alive but thats because that rpm is no longer a normal driving fuel economy using period int he rpms range in which the ecu advances the TIMING on the cam shaft considerably to allow more power to be made..

VVTL-I the key feature is the L in which THAT means lift... a motor to work specifically on lift and timing... these are motors in toyotas higher power cars (lexus's) they work on a similar vvti pattern how ever work also on LIFT duration which is more similar now to hondas i-vtec...

VVTI- AND HONDAS IVTEC ARE NOT the same.... honda designs their motors to create power at 1 point (vtec) toyota cerated their motors to have continous timing changes to created power through out the power band....

VVTI only works on the intake cam also.. not on the exhuast.. anyone who has ever opened up the valve cover will see the exhuast side having no cam adjustment system and the intake side having a large disc which continuously controls the timing on the intake side...THIS IS NOT SIMILAR TO VTEC MOTORS in which both sides are affected by timing...I KNOW THIS CUZ IVE WORKED ON BOTH MOTORS....AND HAVE OWNED AND BUILT BOTH...

here is more supporting and correct information that will explain vvti- vtec and vvtli

http://www.billzilla.org/vvtvtec.htm

http://www.billzilla.org/vvtvtec3.htm

IF YOU WOULD LIKE ME TO GO INTO MORE DETAIL I'D BE HAPPY TO!
if you want more supporting links blah blah blah there are so many on scion life saying the same crap i just said it hurts my brain to think of it...

thanks and have a nice day fellas and a happy after new years first day.....

and if your dumb enough to compare japanese motors and american motors and how they work and are built you should just sit infront of your tv, have a beer and go watch nascar and leave posting on the internet to those with more brains...

Originally Posted by davedavetC

no difference between 07 and 08 man