gude-head-1NZ-FE

[Parmas]

Originally Posted by xbgod

Keep in mind I did away with the VVTI which is also why my cam grind is full race as well as microtech only allows me to turn on vvti which makes it more like vvt.

Through my experience building my custom setup, the VVTi on our engine is one of the main points that play a good role what power and torque across all rpm range is.

That depends what the owner intend to use the car for . It could run on street or race or both. I chose both and for me the VVti is essentially needed on street where I am not always on the 6k rpm range. With the VVti tuned correctly you get a good power and torque all across the lower and higher rpms (which is nice to see a good feel only at 3K).

In your case, I don't think you care of low/medium rpm ranges since yours is built for race purposes. If I were you, I would lock the cam at a desired angle (depending what the dyno shows you) and eliminate the VVti completely.

[xbgod]

Your thoughts are some what like mine on this. Here is what were doing.

first tune without the vvti on


Second tune with vvti on

third with no vvti and lock the cam angle

of the three we will see which is best.

Gotta see how the Gude cams and new throttle body respond to the motor.

XBG

[Parmas]

Originally Posted by xbgod

Your thoughts are some what like mine on this. Here is what were doing.

1 - first tune without the vvti on

2 - Second tune with vvti on

3 - third with no vvti and lock the cam angle

of the three we will see which is best.

Gotta see how the Gude cams and new throttle body respond to the motor.

XBG

1 - You mean with the Cam timing connector disconnected - which would be fully retarded.

2 - Are you sure your management can fully control VVTi? Do you have pics of the management software part?

3 - Do you mean locking temporarly the angle? By the use of the engine management or by locking it directly from the head?

[H3LlIoN]

Originally Posted by Parmas

I chose both and for me the VVti is essentially needed on street where I am not always on the 6k rpm range.

Haha I hit redline pretty much every time I drive the yaris.

[rob323]

I just wish the F1 technology that Honda had years ago, with solenoid actuated valves would hurry up and become main stream. No cam shafts, just fully adjustable valve timing and lift, perfectly optimised for all loads and all rpms.

[H3LlIoN]

bummer. hope you get your new class soon.

[Jason@SportsCar]

Originally Posted by H3LlIoN

bummer. hope you get your new class soon.

The class change I have been pulling for is for autocrossing, nothing to do with our road race classing. Neither allow a "modern" car to change intake/TB. The current OE stuff is so much better than what cars had even ten years ago that you could not make the cars perform equally. Its one less than to worry $$$$ about.

[xbgod]

Ok here is one pic. go to my engine build under forced induction for the rest.

XBG

[Jason@SportsCar]

Originally Posted by xbgod

Ok here is one pic. go to my engine build under forced induction for the rest.

XBG

Trying to overcompensate a little? Is the NX really necessary with the FI?

As long as you are going all out, why don't you ditch that boat anchor of a battery and pop for one of the new Braille lithium-ion units.

[H3LlIoN]

he's sponsored, by NX amongst others.

[H3LlIoN]

Not as shiny as Aras', but I got the CAI back in, and just got done installing the NST underdrive set. Next is Gude TB, as soon as I get it back from Gude.

[xbgod]

AT least it's a clean set-up.

XBG

[H3LlIoN]

Thanks, but I need a wire tuck like WHOA.

[Parmas]

I am not into Microtech but I happen to have experienced similar engine management previousely that only is capable to activate a valve and not constantly vary angles. I am about sure to fully control the VVTi you need to change management.

In my opinion with your cam setup you will surely have nice power and torque on the upper curves ( probably above 6K depending how wild it is). But this would cost you power and torque performance at low and medium rpms. Also you should know that with these cams, there is a possiblity of a rough with rich mixture which result into an unsteady idle especially if you lock cam angle.

[H3LlIoN]

Originally Posted by Parmas

Also you should know that with these cams, there is a possiblity of a rough with rich mixture which result into an unsteady idle.

I'm pretty sure "rough@idle" is synonymous with aftermarket cams, ESPECIALLY with the friggin' profile Aras is running. He's gonna need SRB's to get that thing going!



BTW...got these today.

[Blown_xa]

I can tell you what messing with the vvti will do:

left on the car will lose power when boost hits, it may even fall on its face at high rpm. Spool up and bottem rpm range power will be good.
left off you will make as much power as your setup can make (assuming mbt) , but you will lack slight torque under normal driving conditions. In reality thats not gonna matter because you will be able to light up 1st thru 3rd easy regardless.
When we tune vvti via Haltec on our tC or my car, we find it so far to be time better spent elsewhere .
My advice for xbgod, focus on the basics at hand. 30psi tune, dont start tuning with a 8psi wastegate spring (boost controller maxed wont get u to goal). stuff like that. maybe have ur microtec control silinoid to get better spool and boost curve. greddy controller has gain control but still not as nice inputing duty cycle per rpm. that will make more difference than vvti.

[cali yaris]

I use the M400 on my tC, it's an awesome management unit.

[ilikerice]

all this talk about vvti is making me think that its a P.O.S. for performance and only good for gas savings (of course thats what the yaris is all about)... having doubts about the upgrades i decided to go with now and thinking i should stop with the yaris and see what else is out there to start a new project on... someone give me a reason to throw a kaaz lsd and supercharger/turbo on this car... cuz this talk about tuning the vvti is really throwing me back.. vtec on the crx is so much more simple.