Celica Forums General Discussion General wondering about any vvtl-i modifications on a 00 GTS

I was just wondering if anybody heard anything about any kind of modifications that can make the vvtl-i kick in sooner, or allow me to completely control when it kicks in. Any news on the subject would be greatly appreciated.

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no. I dont think so.

The PowerFC apparently will do that for ya.

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Lowering when it kicks in will make you lose power, but go for it if you wanna pay 1k for the PFC.

Can someone explain why lowering lift makes you lose power? I can never understand that.

On the Dyno it kicks in 30hp, and also by going into lift it breaths in much more air/fuel...so how would making go down 500-1000rpm really hurt that much? Just curious.

can't wait for lucky or illusive or someone else with a PFC to chime in.

Basically they tried to lower it, and then tested it on the dyno and it lost power. They can explain it better than I can, but basically it's because it bogs the engine down too much (I think).

^yeah that's what i think too...our engines seriously lack the brawn to be able to use that lift at a lower rpm...but they can seriously wind up...

the point in lowering lift would be so taht you could stay in lift easier and longer when you shift, right? Well if you get the PFC...you can raise the rev limiter enough so that you can stay in lift when you shift...all while revving at higher rpm's and making more power.

at least that's what i think...lol...again the celi gods can correct me if i'm wrong

i hear tpr is working on somehtign

Oh so that's what the Power FC can do, raise your rev limiter so its easier to land lift. I always thought it can actually change the lift engagement point...but I was highly doubting that!

I kinda get why lowering lift isn't a good thing.

What's rev limit is "safe" enough so you can land lift but not blow up your engine?

I believe lucky uses 8600. he really takes good care of the car though, if you're driving up in that range you'll put more stress on your engine.

not entirely sure, but I have an idea of why raising lift possibly could decrease HP. It's a different cam profile. the whole point to VVTL-i is to be able to have basically 2 sets of cam's in one. it's like a V-Tec and it's supposed to keep a more even torque curve so you can have more low end torque and more high end HP. when you hit lift your in the High end horsepower cam profile while before it your in the low end torque cam profile. the best of both worlds. so I think if you lower lift it could cause you to lose some torque and consiquently HP because the RPM of the engine isn't as well matched to the cam profile. but to me this wouldn't cause you to lose high end HP because it should still be the same as if you were in lift at 6200rpm, but might cause loss of power below 6200rpms. But I have heard that you actually can lose HP due to lowering the lift engagement too much, I dunno if this refers to HP curve below 6200rpms or if it's overall max HP.