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nz_vr4_nz
19-04-2004, 04:14 AM
My VR4 is stock..what will the boost psi be stock? and how do I make it more, how much can I bump it up to so I dont wreck anytthing and

can I up the boost without having to do other mods..
Im only after cheap options..not looking at dragging

KiwiTT
19-04-2004, 05:22 AM
I would recommend leaving it as standard.

Unless you are willing to strengthen other parts as well. One member, boosted his and his transmission broke. :noshake:

Other than de-catting and Air-Induction, like mine, and concentrate on the things that make this car special. i.e. it's handling, cornering, etc., which is good tyres, good brakes, good suspension.

260-300hp is plenty for most. 0-60 in 6sec, 150 mph is enough for most.

What do you want from your VR-4 ? Fast Cornering or Fast Acceleration.

Mine has the good suspension and cornering around 60kph corners @ 100kph is enough satisfaction for me. :cool1:

Spirit
19-04-2004, 07:24 AM
Standard is 0.7bar (10.15psi)

I run mine wth a Blitz Dual SBC Spec S boost controller, others have the Apexi AVC-R, and some the HKS EVC range. It is considered up to 0.95 - 1.0 bar (13.8 - 14.5psi) is safe with standard internals - in fact I ran mine at this on a rolling road recently and all was fine with fuelling etc up to 160mph and peaked at 0.92bar :-D

There are mechanical boost controllers available too.

Hope this helps

Pete

valmes
19-04-2004, 12:35 PM
In fact internals can handle a lot more power then stock... if it's produced right.

Boost controllers (even the most sophisticated ones) can only increase the amount of air "pushed" into the engine... That's good, but not if you are not supplying enough fuel to make the right mixture! …and ignoring other important things... Well, not you of course, but ECU of your car.

ECU has limited amount of data stored for most driving conditions... It even has some amount of built-in safety - fuel maps for higher than standard boost (your ECU doesn't know what boost is - it calculates Air Flow... but that's another story). This gives us (VR-4 owners) chance to up the boost a little and increase power for most situations... but will get fuel cut more often when driving hard (another safety feature of the ECU - when it doesn't know how much fuel to provide - it just cuts it, to be on the safe side).

You can get rid of this safety lock on your car(HKS FCD or Greddy BCD), but it's risky... and not worth it. When your car is out of the data it will try to make a rich mixture, but if boost is too high - your pump and injectors won’t be able to provide enough fuel... and you will end up looking for a spare motor.

S-AFC, E-manage and other piggy back computers can only change values up and down of what's stored in ECU... so they are just an expensive toys...

The only solution is to replace stock ECU with aftermarket one(with data for higher boost, fuel, ignition etc). It will get your car "safe" - 400-450PS (some stuff will still have to be changed, but without mods to the engine). Aftermarket ECUs cost from 1200$ and up... (APEXi Power FC is the cheapest one... there are others also: Autronic, AEM, Motec, Mines VX-ROM etc.)

If you want cheap power - get yourself MBC or a Bleed Valve (same thing anyway) and adjust boost within the safe limits of 0,6-0,9 bar.

Sorry for my English...

pjjohnson
19-04-2004, 01:22 PM
Your English makes perfect sense to me.

nz_vr4_nz
20-04-2004, 01:06 AM
do I need to strengthen any internals if a bleed valve is installed?..hahaha I dont even know what a bleed valve is ???

valmes
20-04-2004, 05:39 AM
Brilliant Boost (http://www.autospeed.com.au/cms/article.html?&A=0028)

You won't be able to push your boost too far... so you don't need to strengthen "any internals ". Well you might want to change your BOV... it looks... it's made out of plastic... :)

Make sure you can see the effect of opening your bleed valve... Go slow. Boost spikes should not go over 0,9-0,95 bar.

simpsonm
21-04-2004, 12:18 PM
I aint looked as yet, but are the actuators adjustable on the VR4. I remember adjusting the boost on my Pug 406 turbo by winding it out a little. Saves buying bleedvalves etc.

EdmundVR4
22-04-2004, 04:06 AM
Yes you can raise the boost easily & safely without any other modifications. When I got my manual VR4 boost was at 7 psi. By installing washers on the actuators the lowest boost level increased to 10 psi. And I have my Apexi AVC-R set at .95 bar (about 13.8 psi). I think 11 psi with stock fuel delivery is safe, keeping in mind that Mitsubishi's usually run rich (safe) on fuel.
Use highest octane fuel available & don't be reckless with this high performance auotmobile & it will serve you very well.
There is quite a difference between 7 & 10 & 14psi. I run high boost 99% of the time, but I listen carefully for detonation here in hot Trinidad. Just love to feel that power under the right foot.

dickytim
22-04-2004, 05:30 AM
forgive my ignorance but what is a washer that you fit to your actuator ? and how is it done ? do you mean washer as in spacer ?

simpsonm
22-04-2004, 10:07 AM
I think that is what is meant. On some actuators like on my old Pug the actuator hag a bolt thread on the end of the arm. This allowed you to screw the link arm out from the actuator itself increasing the boost. Or if you were scared screw it in to reduce the boost and prolong the life of yer turbo and actuator.

EdmundVR4
22-04-2004, 11:52 AM
You guessed right & SimpsonM is correct...spacer as in washer. I put 4 washers on each actuator & that raised the boost to 10 psi. Very safe boost level !

nz_vr4_nz
25-04-2004, 09:17 PM
guess I need to see a mechanic to do that washer business cause im as dumb as bricks when it comes to cars..They probably charge me alot for what sounds like a simple proceedure..
I meet up with a old school mate a few weeks ago who is a mechanic and drags too, he was telling me that he connects modified paint spray cans on to the turbo its self to increase boost time..says its cheap and works a treat and is safer than increasing boost the usaual ways...
said he wold do it for me ..but I dont know aye..It sounds a bit dodgy

simpsonm
26-04-2004, 11:22 AM
Never heard of this method before. You will have to get him to explain what hes doing.