...and therein lies your error Harvey. You are assuming that there is logic underlying these purchases, and that the overriding priority of the owners is the performance of the car. How small-minded you are!

 

Both me and my girlfriend (Gina G-force) have been running Forge VTA DVs on our MY02 STi and MY99 Turbo for the last 18 months with out problem. The main reason for fitting mine was to get pops from the exhaust, which it gave very occasionally, and much less than I hoped for. The only other affect it had on the Sti's performance was some jerkiness when coming off a heavy throttle.

Like many people I have read some of the comments on SN about the damage that VTA DVs may do to an engine - especially Grease Monkey's comments and didn't really believe them. However, last Monday I put the original DVs back on both Scoobs. Both Gina and I immediately noticed a difference for the better. Both Scoobs seemed faster and smoother with better pick up after changing gear. Also on the STi I now crackles and pops from the exhaust when I blip the throttle at idle after a run

The VTA DVs will be staying off both Scoobs for now

 

i find my MY93 runs alot better, and smoother (if i scooby can run smooth!) withe the original plastic recirc dv on. But on a sat night the vta on gets fitted for the boy racer cruise round warrington!

 

u saying u run your scoob without a DV?? wont your turbo go bang pretty soon?

i heard u cant run the Turbo 2000 models without a dump valve????

 

I think Hugo was saying that he runs his car with the standard DV. However, it is possible to run the car without any dumpvalve on it. Turbo life does reduce, but, depending on which you use, not to an overwhelming extent.

If you're talking about a UK market Impreza Turbo 2000 AWD, the TD04 and TD05 turbos cope reasonably well with it. VF's are a bit more of a lottery.

 

sorry this may be a daft question, if atmospheric dump valves do nothing for imprezza's performance! correct me if im wrong but dont the rally imprezza's use them

 

Had a Fordge....No Good...keep away...

Sam

 

They do do "something" for the Impreza (with one z)'s performance, they make the performance worse.

In any case, you're wrong. The rally Imprezas don't use atmospheric dump valves. In most cases they don't use dump valves at all.

 

The WRC cars may not have a BOV. but plenty of Group N and A rally impreza have them fitted.

 

Does a after market re-circ valve improve anything over the factory fitted one?

 

I had a forge vta dumpvalve,

for about 1/2 a day!
I thought my std spec one was leaking.
tried to fanny about with the shims and springs to minimise the noise but alas it was sold on scoobynet the day after.
standard one made everything feeel right and thats the way Im staying, if I had to fit one (i.e. front mount) then it would be recirc all the way.

Andy

theres a guy with an RS turbo in the next street and he delibrately sets off the damn thing when he pulls up to his drive, all the neighbours make a funny hand gesture as though they were trying to get the last of the ketchup.
not my cup of tea

 

I used to a have an aftermerket (forgot the make) Re-circ DV when my original broke (vacuum fitting broken off and bodged repaired- by a heavy handed main dealer mechanic )

When fitted with a cone filter it was noisier than VTA ones! It never gave any running problems...BUT

It chattered like a Australian in an Antartic ice pool, it also induced wategate chatter too - which is not that healthy for the wastegate nor the turbo. It was fully adjustable, but no matter what setting I used it would still do it, unless reduced the spring pressure so the thing was opening at idle and at the slightest hint of vacuum, which obviously was not advatageous performance wise.

Now repaired the original with something abit stronger than superglue (super steel epoxy resin). And now enjoy the noise and performance