Vf52 experiences vs 46

[Manaz]

you really get to focus on just the steering, rather than driving the whole car...

Minor corrections made.

You forgot the braking and acceleration.

[peadya100]

OK... finally i have a definitive answer to this post

Today i had my car retuned after installing a VF52.. the only difference was the turbo and a 3 port boost solenoid.

The results are:

- Power went from 180kw-193kw.

- Boost pressure went from 18psi-19.5psi

- Increase in lag time - None at all

- Increase in tourque - None at all

In summary, the car feels substantially faster even though there was only a 13kw gain and no gain in torque. Honestly feels like a 30-40kw gain. Maybe someone who knows more about dyno graphs than me can explain to me why that is.

This graph shows my previous tune, with my new tune... pretty clear what the differences are now.

[KiDo_Tuning]

OK... finally i have a definitive answer to this post

Today i had my car retuned after installing a VF52.. the only difference was the turbo and a 3 port boost solenoid.

The results are:

- Power went from 180kw-193kw.

- Boost pressure went from 18psi-19.5psi

- Increase in lag time - None at all

- Increase in tourque - None at all

In summary, the car feels substantially faster even though there was only a 13kw gain and no gain in torque. Honestly feels like a 30-40kw gain. Maybe someone who knows more about dyno graphs than me can explain to me why that is.

This graph shows my previous tune, with my new tune... pretty clear what the differences are now.

You picked up 10% wheel torque from 4200rpm to 5600rpm as you would expect/hope with 4+psi more boost, your peak torque is about the same(3600rpm) but you have nearly 800rpm of auto slip at peak torque... 150kph is 6220rpm and thus 75kph should be 3110rpm same as 100kph should be 4140rpm but is closer to 4700rpm. That would explain the missing torque in the midrange that 4psi should generate etc

It could be that the dyno tuning overheated the box and the road performance feels better once there is less slip

[peadya100]

Yep... that all went over my head matt hahaha

You might be right about the cooler box though.

It wasnt a 4psi increase though, it was only 1.5psi increase from the last tune. Or are you talking about the increase from stock?

[KiDo_Tuning]

Yep... that all went over my head matt hahaha

You might be right about the cooler box though.

It wasnt a 4psi increase though, it was only 1.5psi increase from the last tune. Or are you talking about the increase from stock?

19.5psi at 5020rpm vs the old 16.5psi(I read it as 15.5psi when I first glanced at it) is 3psi difference

[peadya100]

Oh I get you... youre not talking about peak psi, youre talking about the boost differences at the particular rev range.

[dja]

Jesus almighty, how did i miss this thread.

Some really, REALLY good opinions here backed up by facts, not by the OP.

Newbie, real world, as you have agreed, then disagreed, then convinced yourself again, a VF52 is a worthwhile upgrade, i seriously doubt you will notice any lag. and it will kick harder etc, anf vf46's are really too small for our engines.

There is real world evidence of this, its a great streetable turbo.

Just buy one, be done with it.

i understand the research as much as possible philosophy, i live by it, and its a fool who takes every mans advice, but a bigger one who listens to none. I think by this point you can safely bet that the VF52 with supporting mods(tune etc) will net great gains with minimal to no down sides.

Mick, i feel your pain mate

[bigBADbenny]

http://legacygt.com/forums/showthread.p ... l?t=178684

The link that answers every question here...

More goodness FYI :
http://legacygt.com/forums/showthread.p ... 73358.html

So many answers in the stickies on LGT and Nasioc.
Now to ask the right questions

[GT-B Spec R Pilot]

A very interesting thread... the most obvious question to me would be how much power can an engine with stock internals handle reliably? By that I mean when used as an everyday drive where you are not at w.o.t. all that often. Discounting external supporting mods which are relatively easy (compared to an engine rebuild) is the engine the liming factor or would the clutch / gearbox (either manual or auto) give up first?

It seems to me that all the external mods you can imagine ultimately lead to a limitation in either the engine or gearbox power handling capacity if these are left as stock. Some great advice in this thread though... Cheers

[bigBADbenny]

It's probably got more to do with the safety factor and headroom provided by the tune and supporting mods.
In conjunction with the attitude and awareness of the driver.
After that the question is for how long.
We're seeing knock and boost related failures at all power levels standard and over.

Unopened engine: 135-240ish (claimed) KW atw.
Max boost limit before heads lift: 21ish psi.

[scary]

My big question is why the hell are the cars being run up in 3rd gear!!! or is it just for penis stroking?

Way to inflate the torque and power figures!!

Get it run up in the right gear and we can all see what it is actually making.

BTW VF52 is a waste of time on anything other than a dead stock engine

[peadya100]

My big question is why the hell are the cars being run up in 3rd gear!!! or is it just for penis stroking?

Way to inflate the torque and power figures!!

Get it run up in the right gear and we can all see what it is actually making.

BTW VF52 is a waste of time on anything other than a dead stock engine

Thanks for your insight scary.... They always dyno the autos in 3rd gear... but you probably know better than the tuners

P.s. not everyone is worried about a peak power figure for as you put it "penis stroking".. VF52's are about gaining extra performance without sacrificing drivability. Living in sydney I can tell you its hard enough finding space to spool up the VF52 let alone bigger turbos that hit full boost at 4000+ rpm.

[rada0469]

BTW VF52 is a waste of time on anything other than a dead stock engine

Scary by dead stock do you mean without supporting mods or without internal strengthening? Genuine question.

[KiDo_Tuning]

It's probably got more to do with the safety factor and headroom provided by the tune and supporting mods.
In conjunction with the attitude and awareness of the driver.
After that the question is for how long.
We're seeing knock and boost related failures at all power levels standard and over.

Unopened engine: 135-240ish (claimed) KW atw.
Max boost limit before heads lift: 21ish psi.

FYI: Inlet manifold boost pressure does not lift heads, cylinder pressure lifts heads.

[bigBADbenny]

Thanks for the clarification.
I'll have to hit the books.
Q: what is the relationship between cylinder pressures and manifold pressures?