ScrappyDoo2

Okay, now I know from searching the threads that this is a common topic but I still can't seem to get an answer to settle on.

I have an 02 WRX which is going for the Tek2 with decat at PE on Weds. I had bought a forge VTA DV a few weeks back and have been running it fine since. However I have recently been told conflicting information as to whether a VTA is better than a recirc. I understand that a VTA causes momentary overfueling as the ECU accounts for the air that should be returned to the inlet and this can cause a few pops and bangs. Therefore on a technical level the recirc should be better. I also noticed that Merv at PE has the standard recirc on his WRX which is around the 300BHP mark I think. As does Graham at TSL on his Motec'd WRX. These guys know a thing or two about making scoobs go faster and therefore in terms of outright performance over nice noises the recirc must have an edge or else they would have changed such a relatively cheap part??

I swapped my forge back to the factory DV this morning and went for a drive it seemed to hold boost well according to my SECS but I seem to think that response when changing gear was perhaps quicker to pick up again with the forge or maybe I'm imagining it??

On another note, I noticed that when I had both off you couldn't really push the recirc piston up with your thumb whereas you could on the forge, would that mean that under boost load the forge may be prone to leaking a bit of boost out?

Help any tech-heads out there who can sort this out once and for all. I'd like an answer before weds please so I can take the car to PE to be mapped in the correct state???

Cheers
Greg

ADP

Cant give you a full on science answer, but I use my modded my02 for competition, and I run the standard dump valve, did have a forge but didnt like what it did. Its now gone.

ScrappyDoo2

Thanks for the response what didn't you like about what your Forge did out of curiosity?? Do you know if the factory unit is okay still once the boost has been raised (Tek2 round the corner) must be as I'm sure your car must be running higher boost for competition use?

ADP

no not running higher boost, just full decat, proper suspension, brakes etc

The thing I didnt like about the Forge was that if you gave a big lift or were balancing the on the throttle it went pish and basically unsettled the car. As far as I was concerned it was a max power accesory(but like I say, this is from a drivers experience not a scientific statement)

john coffey

Dump Valves are a waste of money IMHO, spend the money on something else like the bumpsteer mod and a full 4 wheel alignment.
The MY02 has a perfectly good re-circ dump valve, if it aint broke don't fix it unless you particulary want the psst noise.

v5 man

iTrader: (4)

i recently spoke to PE about dump valves. they advised me that the original re-circ type is fine for 300 bhp, after that a ptshhh type would be better.

ScrappyDoo2

Thanks guys,

I thought so, particularly when I saw Graham at TSL and Merv at PE both running the standard DV - knew there would be a reason for it. I too didn't like the Forge dumping on part throttle don't understand why it would do that really?? But you're right it does unsettle the car making it jerk of boost suddenly. I also bought the Samco intercooler/turbo hose kit the other day in prep for the Tek treatment and felt a bit gutted that the DV to inlet piece was sitting there redundant - but not anymore! I still think one of the best mods was having the eibachs and geometry setup with uprated droplinks down at TSL - top work guys, like a different car!

I guess I'll be selling the Forge then (will pay for optimax needed for the trip to PE and back ;-)

Cheers

Turbo_Steve

Each to their own.

Had a forge: didn't like it. Have since been told it needed a stronger spring (and that was a re-circ!)


I currently have an HKS SQV (I was told it would be quiet! YEAHR RIGHT!) and it dumps smoothly and gently at part throttle, doesn't effect the engine at all, just a little "fsst" (sounds like a budgie whistle!) if you lift off gently, a slightly large one if you lift off harder.

I DID find it made gear-changes quicker (god knows why). And before you all say "placaebo effect" I timed this, and there is nearly a .7 second distance to 100mph from a standing start.
This COULD be down to air temperature, but the gearchange "felt" different, and even passenger said it looked like I was "slamming through the gears faster". It's a personal preference thing, I guess.

chockymonster

Turbo_Steve,
I've done the same, dropped the forge and gone for an HKS
much nicer sound, especially with a blitz SUS