Benefits of going VVT-i? Options

[Random_Stranger]

Ok, so I just found out that VVT-i was like dual variable valve timing for HP and TQ. So anyone know how this is beneficial or worse in let's say a 3sgte engine? As I am aware there is a 4th gen engine that has this VVT-i technology (I think).

(I had made a n00b out of myself with the original posting, so I made this thread up to make up for it in another n00bish fashion, but with more to gain from it than my original thread, so my bad.)

This post has been edited by Random_Stranger: Dec 28, 2009 - 6:58 AM

[Supersprynt]

It helps in creating the most efficient timing over the entire RPM range.

http://www.etoyotaindia.com/flashpopup/vvti.htm

This post has been edited by Supersprynt: Dec 28, 2009 - 5:11 PM

[BonzaiCelica]

Actually the 4th gen 3sgte that came in caldina st215 does not have vvt-i.

4th gen 3sgte Specs from what I know:

-Air to Air Intercooler
-Better designed intake manifold
-No distributor (4 individual coil on plug)

thats about all I know. Only the 3sge beams redtop has vvt-i on the intake manifold, which Im sure you aware of.

[96bluevert]

^^What he said. Only the BEAMS 3sge had VVT-i in the 6th gens.

[Random_Stranger]

^^What he said. Only the BEAMS 3sge had VVT-i in the 6th gens.

Then is it true that the black top Beams engine ran the Dual VVT-i?

[Supersprynt]

Yes, the black-top Altezza beams had dual (intake & exhaust) vvti.

[manphibian]

As i understand it, variable valve timing is more about emmisions and economy than it is performance......

[Random_Stranger]

Yes, the black-top Altezza beams had dual (intake & exhaust) vvti.

Oh ok, cool thanks

As i understand it, variable valve timing is more about emmisions and economy than it is performance......

Oh, so that's why nobody really likes it then. But don't they still produce more TQ than Vtec engines?

[Supersprynt]

They help overall efficiency. Power, fuel economy, emissions. There's not a whole lot of power to be gained. VTEC is essentially the same thing. Both are timing controllers.

[Random_Stranger]

They help overall efficiency. Power, fuel economy, emissions. There's not a whole lot of power to be gained. VTEC is essentially the same thing. Both are timing controllers.

Oh ok, but don't all variable valve timing on engine by different make have essentially a specific design that separates them? I am certain most of you are saying "Faust! Read on it foo!" but this is just for discussion sake. Because as I said, I failed big time on the original thread and so I just put this up instead. Otherwise I would have just deleted this thread if I had the ability to.

Like, for instance, if VVT-i were included in a newer 3sgte engine, would anyone be interested in that? Just going off of what they know about the 3sgte, and what they know about VVT-i and it's properties.

This post has been edited by Random_Stranger: Dec 28, 2009 - 7:04 PM

[HaysoosKreesto]

I would be quite interested if they ever came out with an updated version of 3sgte .

[Supersprynt]

They're not exactly the same, but they are the same concept. VVTi is now VVTLi - which includes lift and can be found on most Toyota motors.

[Random_Stranger]

They're not exactly the same, but they are the same concept. VVTi is now VVTLi - which includes lift and can be found on most Toyota motors.

Oh ok, and those are "Dual", yes?

[Hanyo]

As i understand it, variable valve timing is more about emmisions and economy than it is performance......

that is not entirely true.

vvti is only for emissions on the eco box motors aka 1zfe.

But once you get into the IS-F engine, you will get vvt for horse power.

[Hanyo]

They help overall efficiency. Power, fuel economy, emissions. There's not a whole lot of power to be gained. VTEC is essentially the same thing. Both are timing controllers.

Oh ok, but don't all variable valve timing on engine by different make have essentially a specific design that separates them? I am certain most of you are saying "Faust! Read on it foo!" but this is just for discussion sake. Because as I said, I failed big time on the original thread and so I just put this up instead. Otherwise I would have just deleted this thread if I had the ability to.

Like, for instance, if VVT-i were included in a newer 3sgte engine, would anyone be interested in that? Just going off of what they know about the 3sgte, and what they know about VVT-i and it's properties.

vvti doesn't really help with turbo charge engines because under boost the air restriction bottle neck would be lessened. VVTi was orginally created to help all motor engine breath better while maintaining torque. This is the same reason why you dont see motorcycle engines with vvti. They don't need torque so everything part of that engine can be geared towards reving up and making a ton of horse power.

Reving a turbo charge engine that high is simply not a good idea.

To really beat a dead horse, vvt was design for all motor engines to shift the power band higher into the RPM range with out the consequences of no torque, bad idle, bad fuel economy.

[richee3]

vvti doesn't really help with turbo charge engines because under boost the air restriction bottle neck would be lessened. VVTi was orginally created to help all motor engine breath better while maintaining torque. This is the same reason why you dont see motorcycle engines with vvti. They don't need torque so everything part of that engine can be geared towards reving up and making a ton of horse power.

Reving a turbo charge engine that high is simply not a good idea.

To really beat a dead horse, vvt was design for all motor engines to shift the power band higher into the RPM range with out the consequences of no torque, bad idle, bad fuel economy.

Everything needs more torque

Nah, just playing. But seriously, this thread is a good read. I thought VVT was good for both more power and improved efficiency, not just one or the other. I am getting a good education from you guys.

[Rusty]

vvti doesn't really help with turbo charge engines because under boost the air restriction bottle neck would be lessened. VVTi was orginally created to help all motor engine breath better while maintaining torque. This is the same reason why you dont see motorcycle engines with vvti. They don't need torque so everything part of that engine can be geared towards reving up and making a ton of horse power.

Reving a turbo charge engine that high is simply not a good idea.

To really beat a dead horse, vvt was design for all motor engines to shift the power band higher into the RPM range with out the consequences of no torque, bad idle, bad fuel economy.

did you hear about the tom's tuned altezza came out blacktop VVTi 3S-GE+T , only 100 where made (came out with heaps of toms stuff like ecu airfilter suspension exhaust and among other things) there is also a 3S-GZE (blitz supecharger)

or the updated 1jzgte (vvti turbo) or 2jz-gte (vvti turbo)

[Random_Stranger]

vvti doesn't really help with turbo charge engines because under boost the air restriction bottle neck would be lessened. VVTi was orginally created to help all motor engine breath better while maintaining torque. This is the same reason why you dont see motorcycle engines with vvti. They don't need torque so everything part of that engine can be geared towards reving up and making a ton of horse power.

Reving a turbo charge engine that high is simply not a good idea.

To really beat a dead horse, vvt was design for all motor engines to shift the power band higher into the RPM range with out the consequences of no torque, bad idle, bad fuel economy.

did you hear about the tom's tuned altezza came out blacktop VVTi 3S-GE+T , only 100 where made (came out with heaps of toms stuff like ecu airfilter suspension exhaust and among other things) there is also a 3S-GZE (blitz supecharger)

or the updated 1jzgte (vvti turbo) or 2jz-gte (vvti turbo)

Sweet find! Any specs?

[hatchy_gt-s]

As i understand it, variable valve timing is more about emmisions and economy than it is performance......

that is not entirely true.

vvti is only for emissions on the eco box motors aka 1zfe.

But once you get into the IS-F engine, you will get vvt for horse power.

acually the IS-F has vvtli so it controlls lift allowing it to reach higher rpms due to increased valve lash. the 1zz uses vvti and the 2zz (found in 7th gen GT-S celicas) have vvtli, that is why you hear them say "I'm hittin lift"(worse saying ever). BUT none of this is useful without high compression ie the 1zz and 2zz have 10.5/11.5to1 comp. and the 4age 20v came with vvt(vacuum opp.) also high comp.

[Hanyo]

As i understand it, variable valve timing is more about emmisions and economy than it is performance......

that is not entirely true.

vvti is only for emissions on the eco box motors aka 1zfe.

But once you get into the IS-F engine, you will get vvt for horse power.

acually the IS-F has vvtli so it controlls lift allowing it to reach higher rpms due to increased valve lash. the 1zz uses vvti and the 2zz (found in 7th gen GT-S celicas) have vvtli, that is why you hear them say "I'm hittin lift"(worse saying ever). BUT none of this is useful without high compression ie the 1zz and 2zz have 10.5/11.5to1 comp. and the 4age 20v came with vvt(vacuum opp.) also high comp.

i was just generalizing variable valve timing and wrapping up the entire valve timing in a short phrase of vvt; because what i said applies to vtechi and nvcs and what ever those crazy manufactures want to call it.

vvt is some fancy technology. nissan's nvcs variable valve timing was able to use the valves it self to control the engine removing the need for a throttle body.

This post has been edited by Hanyo: Dec 30, 2009 - 4:05 AM

[Smaay]

They're not exactly the same, but they are the same concept. VVTi is now VVTLi - which includes lift and can be found on most Toyota motors.

the only engine with Lift is the 2ZZ-GE in the 7th gen celica.


and you guys have no clue about VVT. yes economy is part of the reason for it, but VVT allows the cams to adjust to maintain a flat torque curve thus the horsepower to rise. goto newcelica.org and look at all the dyno sheets posted. horsepower just keeps climbing and torque remains flat. look at a car like the 3S-GTE. both curves rise then reack peak and fall off. which is why people changes cams. so those curves can be shifted. the benifits of VVT is that with some ECUs and piggyback you can adjust the valve timing making more power. let me give you an example.....in my 7th gen celica. i was making about 415 HP under 25psi. once we started adjusting the VVT tuning. i made over 130HP giving me 545HP.

VVT has amazing possibilities. you just have to know how to harness it

[Random_Stranger]

^^^ That's a fast frigging 7th gen

[hatchy_gt-s]

They're not exactly the same, but they are the same concept. VVTi is now VVTLi - which includes lift and can be found on most Toyota motors.

the only engine with Lift is the 2ZZ-GE in the 7th gen celica. = WRONG!!!

the 2zz came in the lotus, matrix, vibe, corolla xrs,corolla(euro&aussi),99 SS-ii celica

[blu94gt]

A couple different people have hit the answer. VVTI or any variable-valve-timing setup, is to maximize power and efficiency by changing the timing throughout the power band. Here's the explanation an old shop teacher gave me:

Know how old muscle cars and dragsters have a big "cam lope" at idle (sound like they are barely staying running), but they SCREAM when revved up? That's because the timing is non-variable, they opted for a cam that only gives power in the high-end.

Variable valve timing can allow you to use a set of cams that will produce a smooth, efficient power curve, and by changing the timing you can allow for that power to exist throughout the RPM range, rather than just a very specific range.

[HaysoosKreesto]

They're not exactly the same, but they are the same concept. VVTi is now VVTLi - which includes lift and can be found on most Toyota motors.

the only engine with Lift is the 2ZZ-GE in the 7th gen celica.


and you guys have no clue about VVT. yes economy is part of the reason for it, but VVT allows the cams to adjust to maintain a flat torque curve thus the horsepower to rise. goto newcelica.org and look at all the dyno sheets posted. horsepower just keeps climbing and torque remains flat. look at a car like the 3S-GTE. both curves rise then reack peak and fall off. which is why people changes cams. so those curves can be shifted. the benifits of VVT is that with some ECUs and piggyback you can adjust the valve timing making more power. let me give you an example.....in my 7th gen celica. i was making about 415 HP under 25psi. once we started adjusting the VVT tuning. i made over 130HP giving me 545HP.

VVT has amazing possibilities. you just have to know how to harness it

Out of curiosity, how do you keep your tires from spinning? As I understand it, anything above 300 hp is bad tire spin for FWD.

[richee3]

Out of curiosity, how do you keep your tires from spinning? As I understand it, anything above 300 hp is bad tire spin for FWD.

Depends on the weight of the car. For example, a Nissan Maxima/Toyota Camry/any other full size FWD car like that wouldn't spin near as bad as a Celica. In the instance of a 6th gen Celica, you can put a limited slip tranny in the car to reduce wheel spin.

That's an awful lot of power though, and I would imagine wheel spin is unavoidable. It's just a matter of how best to reduce it.

[Smaay]

They're not exactly the same, but they are the same concept. VVTi is now VVTLi - which includes lift and can be found on most Toyota motors.

the only engine with Lift is the 2ZZ-GE in the 7th gen celica. = WRONG!!!

the 2zz came in the lotus, matrix, vibe, corolla xrs,corolla(euro&aussi),99 SS-ii celica

yeah yeah yeah, but it started in teh Celica. of course i knew it came in those other cars.

[hatchy_gt-s]

^ once again no it was the elise in 2004

[garin]

screw the sti and the evo. if there is a will there is a way. if you want it bad enough you will get one. look at pipes. he has a "gt4" in america. there's a real one in philly too. DO YOUR RESEARCH!

manny has a nice write up of the beams 2.0 engine swap that steph and dustin did....

[nics]

http://www.youtube.com/user/magusownz#p/u/47/2vfxnRTqV_k

http://www.youtube.com/user/magusownz#p/u/28/mJ_YSergbPk

corolla xrs vvtl-i power

[Rusty]

Rusty's Post

Sweet find! Any specs?

2JZ
280 ps (205.94 kw) / 5600 rpm 44.0 kg*m (431.49 N*m) / 3600 rpm
with VVTi 280 ps (205.94 kw) / 5600 rpm 46.0 kg*m (451.11 N*m) / 3600 rpm
altough you'd have to see dyno runs of both to see the real difference

will try get more info on the tom's altezza

[Edophus]

to get your head round what vvti brings its worth looking at the beams vs the previous gen 3s-ge

cam specs for the gen 3 3s-ge : Cam duration (IN/EX) - 252°/240°

for the beams : Cam duration (IN/EX) - 256°/244°

there not that different, but how does that explain the power difference, the beams cams give a little extra lift, and it has more compression, but generally these are things that would result in a higher peak power but with a loss of torque further down the revs, but because of the vvti the beams makes more power across its entire power band, which is also bigger because of the vvti, and its important to remember you dont drive around at peak power, you have to work your way across the power band in each gear as you accelerate so all that extra torque the vvti brings is beneficial to performance. The vvti means you can run less duration to acheive the same peak power, and less duration improves the low end torque even more. Tuned beams engines all show a lot more torque and power with the vvti still there, removing it just leaves holes in the powerband.

vvti alone is better than lift/vtec alone for performance, because in a hard tuned engine you will probably want to lose the lift mechanism to save valvetrain weight and just run a fixed cam to get the peak power you want, but vvti has proved its worth retaining for the performance gains. Generally the high lift, high duration cams on a 1.8 vtec engine which then produces less torque but more revs, and runs higher gearing to get more torque to the wheels, is no better than a 2 litre with just vvti, but the 2 litre will be more drivable, and probably produce more torque and power overall with greater fuel economy as it doesnt need such short gearing, as in case of the jdm b18c vs the beams, both ulitimatly offer the same level of performance. I think this is why honda were pretty much alone for the most part in there persuit of variable lift, whilst everyone else went for vvti first. Vtec may have sold cars, but ultimatly its a wonderfull engineering excersise in pointlessness

Vvti is also very beneficial for turbo engines, as you can control the gas flow through the engine so much better, you can use vvti to spool the turbo much faster, theres some official toyota documents about the revisions made to the 1jz-gte, they changed it from a non vvti twin turbo to a vvti single turbo, and gained loads of torque low down with better spool times, quite the opposite of what you'd expect to see if it werent for the vvti, the documents highlight the area of the dyno graph in which the vvti made the difference, will see if i can find it.

This post has been edited by Edophus: Jan 7, 2010 - 11:45 AM

[BonzaiCelica]

very good info Edophus. And it would be more like the B18C jdm spec motor vs the Beams Redtop. the b18c6 only produces 190 hp.

also if I may add one thing. How much power would the beams redtop lose if you were to attach an egr to it.

The reason why I asking this question is becuase the jdm spec integra type r produces 198 hp at 138 lb torque with a 4-1 header, while the USDM spec Integra type R produces 195 hp at 130 lb ft torque. How the hell is that? I know that jdm spec runs 100 Ron = 94 octane, and the usdm spec engine runs 95 ron = 91 octane in California and 98 ron = 93 octane in other states across the U.S.

So how is that that they were able to bring over such a high reving from japan and tweak it so that it only loses 3 hp. Was it the egr that made the usdm spec engine lose 3 hp, or becuase of the lower octane that is provided here in the U.S?

This post has been edited by BonzaiCelica: Jan 7, 2010 - 11:47 AM

[Edophus]

very good info Edophus. And it would be more like the B18C jdm spec motor vs the Beams Redtop. the b18c6 only produces 190 hp.

oh that was the one i meant , for some reason i remembered it as the c6 but your quite right!

corrected i think its a pretty good comparison, my freind had a 98 spec engine (B18C lol) in his 96 spec integra type-r and we both travelled to track days together, my ss3 despite being a bit heavier used exactly the same amount of fuel, i mean we were filling up at the same time and putting in the same amount with only pennies difference, both were tuned to the same level, and one was as quick as the other to the point of putting in virtually identical laptimes, they just both went about it with different characteristics, so highlights the benefits of a vvti engine in terms of its ability to bring performance and economy to the mix.

This post has been edited by Edophus: Jan 7, 2010 - 11:51 AM

[BonzaiCelica]

reply to my long question plz

[Edophus]

reply to my long question plz

I have to confess i dont really know much about egr! i'm just glad the beams doesnt have egr but its not going to help with power, but then its also not usually on all the time as its valve controlled, only time i've come across it was on the honda h22, i guess it'll depend on the implementation. I do think it will have minimal impact though.

as for the integra there is so many differences between the versions of the b series it could just be a difference in spec, i dont know anything about the usdm version, but for example the uk type-r has a really restrictive exhaust manifold that loses it heaps of power, the jdm version gets a really nice manifold, swapping out the manifold on the uk type-r releases quite a bit of power

[BonzaiCelica]

hmm ok i see. Ill just have to ask at the next type r that I go to. Even though I hate going to those things, becuase all the honda guys think there cars are the ****. vtec!!!!

[Hanyo]

So how is that that they were able to bring over such a high reving from japan and tweak it so that it only loses 3 hp. Was it the egr that made the usdm spec engine lose 3 hp, or becuase of the lower octane that is provided here in the U.S?

egr valves are not open during wide open throttle. So when they dyno the different engines the egr would have no affect on the outcome. The only thing i can think of that would make a difference in horse power would they tuned the ecu to run on lower grade fuel and to run cleaner to stick with the american air pollution restriction. But I really dont know the exact answer to the difference in power.

[HaysoosKreesto]

So how is that that they were able to bring over such a high reving from japan and tweak it so that it only loses 3 hp. Was it the egr that made the usdm spec engine lose 3 hp, or becuase of the lower octane that is provided here in the U.S?

egr valves are not open during wide open throttle. So when they dyno the different engines the egr would have no affect on the outcome. The only thing i can think of that would make a difference in horse power would they tuned the ecu to run on lower grade fuel and to run cleaner to stick with the american air pollution restriction. But I really dont know the exact answer to the difference in power.

I think its because the Japanese have a secret plot against America to give them the ****tier stuff, and keep the best stuff for themselves.

[Rusty]

I dont know Hanyo UK spec ST202 with the 3gen 3sge went down to 173bhp due to EGR, (was 178bhp before EGR) JP spec still stayed at 178BHP. only difference I know of is the egr.

could be quite a few things egr, the cat, ecu tune, how they where dyno'd?