GA16DE and variable valve timing

RiceBox · Jun 2, 2002

Does the GA16DE in a '98 Sentra have some kind of variable valve timing. My dad's b14 Sentra really surges at high revs in first gear. It feels like VTEC

but I'm wondering if Nissan had a similar system.

sentra94xe · Jun 2, 2002

Nissan VVL

From what I know, Nissan has a "vtec-like" system called NEOVVL--- a Variable Valve Lift system. I am pretty sure this is not present on any USDM spec motors to date... but can be found overseas on the V-code motors (SR20VE, VET) and others (RB26DETT, RB25DET, etc). The new Z could have VVL.

barnoun · Jun 2, 2002

The GA16DE has VTC(variable cam timing). It adjusts the intake cam timing continuously so you can't really feel it, but at 6600rpm you can feel when the VTC retards the intake cam, reducing power.

RiceBox · Jun 2, 2002

Well if it's not variable valve timing what would make the engine surge like that???

barnoun · Jun 3, 2002

It is variable. As for the surge, I'm not sure, but I think I know what you mean. In my auto, when I drag launch from 1, it starts slow then at about 4000rpm or a little higher it pulls hard to redline. Maybe the VTC is "feelable" then...

AznVirus · Jun 3, 2002

barnoun said:
The GA16DE has VTC(variable cam timing). It adjusts the intake cam timing continuously so you can't really feel it, but at 6600rpm you can feel when the VTC retards the intake cam, reducing power.

ive never heard of this before, id like to know where you found this out. thanks.

barnoun · Jun 3, 2002

I don't remember where I found it out, but do a search on your favorite search engine for ga16de and vtc and you'll get links that say it's true.

James · Jun 3, 2002

it has variable timing on the intake camshaft. that's why there is that lump on your valve cover on the left hand side.

200'side · Jun 3, 2002

There is something definitely feelable passing 6 grand. I dont know too much about internals (and I might get ridiculed for this) but I always thought it was the second cam kicking in or something. But its the Variable valve timing adjusting the intake cam? Ok.

James · Jun 3, 2002

200'side said:
There is something definitely feelable passing 6 grand. I dont know too much about internals (and I might get ridiculed for this) but I always thought it was the second cam kicking in or something. But its the Variable valve timing adjusting the intake cam? Ok.

W/ VTC you don't have the variable lift as w/ VTEC. (VVL has it tho). It adjusts the phase of the timing. Isn't the newer systems called CVTC? Well BMW and Ford also use this type of system... I think Toyota does too w/ their VVT-i and Hondas new VTEC systems also incorporate this technology...

200'side · Jun 3, 2002

Right on. Everyone has their own version. Didn't BMW incorporate it into their new M series. Im sure I read up on it somewhere and it seemed pretty nice.

James · Jun 3, 2002

BMW has it on both intake and exhaust cam shafts and they've been able to do away w/ the throttle body. ford only has it on their exhaust shaft for better emissions.

sentra94xe · Jun 4, 2002

James said:
BMW has it on both intake and exhaust cam shafts and they've been able to do away w/ the throttle body.

Would this be their "VANOS" system?

James · Jun 4, 2002

yep Double VANOS is what BMW calls it.

barnoun · Jun 4, 2002

Double VANOS is their variable valve timing system, but their new system that doesn't use a throttle body is called valvetronic.

James · Jun 4, 2002

it's done through their valves tho, i don't know the details but the cams are on a little ramp and i think the entire camshaft moves so the lift changes depending on where on the ramp they sit...

barnoun · Jun 4, 2002

James said:
it's done through their valves tho, i don't know the details but the cams are on a little ramp and i think the entire camshaft moves so the lift changes depending on where on the ramp they sit...

You mean for the valvetronic right? I think that is how it works.

James · Jun 4, 2002

barnoun said:
You mean for the valvetronic right? I think that is how it works.

yeah that's the one. it's pretty ingenious.

Teknokid · Jun 9, 2002

So does my my 96 GXE have this VTC that you guys speak of?? How is it that it is VTC but it means Variable Cam Timing

James · Jun 10, 2002

Teknokid said:
So does my my 96 GXE have this VTC that you guys speak of?? How is it that it is VTC but it means Variable Cam Timing

Variable Timing Camshaft... yeah you have it on your 96.

GA16DE and variable valve timing

Top Contributors this Month