do turbo cars have vvl?

>>14044334
why wouldn't they?

>>14044343
isnt it diminishing returns with a turbo?

street cars yeah.

race cars, probably not. no need.

>>14044360
why would it be?

>>14044334
turbo cars have no use for vvt, but they have use for vvl.

>>14044388
VVL systems have increased frictional losses that come with having to run stiffer springs all the time, even when not needed with the mild cam.

With the tarbo, if you need more power you just change the wastegate duty cycle and increase the air density in the inlet manifold.

>>14044414
You could construct a convincing argument that the opposite is true.

>>14044417
pretty sure the benefits of vvl far outweigh the immeasurable increase in friction loss.

>>14044431
depends on your boost and backpressure, but in general overlap is less of a concern for turbo cars. valve lift helps no matter what.

not really sure what youre getting at. if you claim theres a convincing argument for the opposite then why dont you type it out

>>14044417
turbos also require stiffer valve springs.
doesn't matter it's still worth it

>>14044462
>but in general overlap is less of a concern for turbo cars
I'm not 100% on that.

>>14044474
>turbos require stiffer valve springs
Why do they need stiffer springs?

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11KB, 411x387px

so if I delete the vtec in a honda turbo engine is it actually better?

Could that be why the new NSx doesnt have vtec?

>>14044530
Pressure in the manifold trying to force its way into the cylinders.

>>14044510
it's only a concern off boost, to get responsive spooling, in comparison to n/a when it's a concern 100% of the time through all load conditions. but, as it adds overlap (if it thinks its still n/a) it will start to hurt potential power at high rpm or loads as more exhaust is left over in the cylinder than if you had less overlap.

I mean if you have really efficient turbo, manifold, and wastegate with good boost control you can get away with adding more overlap but only if you are building some sick ass race motor are you going to start getting into maximizing your overlap and shit and messing with valve timing maps based on your back pressure logs etc

I can't get into it because I'm not a fluid dynamics engineer, but that's basically what I've gathered from reading.

>>14044589
what I mean is.. cam timing and lift are generally less important simply because your intake and exhaust are both pressurized. which is why stock cams are perfectly suitable for basically every turbo build. no point and no real benefits excluding specific turbo cams built around very specific setups.

conversely, even a mildly built n/a motor will have a pretty intense cam with high lift and lots of timing range. they benefit a lot more from it.