Just Curious,

I have my 94 WRX booked in today for the cat downpipe to be replaced with a decat downpipe.

When I get it back I'm going to fit a Bailey Dump valve.

I've heard that it feels like a different car to drive after these 2 mods, is this true? What will be so noticibly different? Bearing in mind I already had a the centre cat decatted with a cat back system.

Thanks!

 

You dont have a centre cat on a 94wrx it would just be a silencer in the previous centre section (although it does look cat like depending on system)

Decat downpipe on mine made the car sound more throaty and helped the turbo spool a bit quicker as well. In cold weather it also caused overboosting. Decat downpipe is a worthwhile mod and in general the car may feel more lively.

The bailey dump valve could reverse the good that the decat downpipe has done. It can cause rough idling, poorer economy and rough running. However there are people who run them with no apparent problems. Subaru decided on a recirc type for a reason (will probably get flamed now by some)

Me, I run a standard recirc, and have a induction kit. I get a dump valve type noise between gears changes that is just right (for me)

 

mine went form downpipe back decdat with tech 3 remap, t oa full decat system with map (tweeked origional) and hell did it make adifference. went from 240bhp 240ftlb to 258bhp 280ftlb, pulls like a train

 

I thought the classics came with a centre cat and downpipe cat?

 

yep, mine had a partial decat before i bought it

 

Does de-catting the downpipe make it really noisey?

I know you won't lose the flat four rumble, but I don't want it going like...
rooooommmmmmwhhhahaa!!!!! and sounding like a crap TVR.

LOL

 

yeah does make it lound, but sounds awesome

 

There's a few WRX's around my area, and I think to myself, that sounds quite loud I wonder if thats got decats.

Be nice to out noise them

 

not a 94. Only a catted downpipe. The centre sections is a bulbous silencer.

A decat downpipe gives it more of a growl!

 

I agree about the bailey dv, mine run's badly too. Seems to vent when at 4000rpm and holding and becomes very jerky.Wonder if the spring is to weak. Will be changing it soon, but not sure what to use.

Tim

 

i have a 94 wrx it came with a lovely blitz dump valve loud and cool but car was searching for idle ckecked everything i could maf lambda plugs coil packs in the end a friend suggested take off dv so for 5£ bought origional dv and hey presto alls well again runs smoooth and still keep a good whoosh on gear change as got induction kit on too (save ya cash)

 

Right, got the car back last night.

I got the garage to fit the Bailey DV at the same time as doing the downpipe decat.

But, when I push the accelerator, you can hear whistling all the way up to the whooosh sound, is this ok? It sounds like its coming from DV?


Thanks

 

is it whiistling or can you hear the turbo spooling up? the down pipe make a huge diffrence to the way the turbo sounds

 

Well I thought it could be the turbo spooling, but It sounds like it coming from the DV, it whistles and the more you put you foot down slowly, the more noise the DV makes then it goes whoooosh.

I may have to get someone to rev on the spot whilst I see if the whistling is coming from the DV. Because even when I rev on the spot it whistles?

 

Just wondering if anyone else running a bailey DV has this aswell?

 

is the car idling OK?

 

Yeah idles fine, runs smooth, everything seems ok, just the DV seems to be making a lot noise. Like I said it whistles all time I accelerate. I thought it realises pressure when you change gear? it sounds like it's always realising pressure?

 

Yeah idles fine, runs smooth, everything seems ok, just the DV seems to be making a lot noise. Like I said it whistles all time I accelerate. I thought it realises pressure when you change gear? it sounds like it's always realising pressure?

sorry added this twice

 

Sounds like the dump valve is leaking.....is it a new one, specifically for an impreza, or was it from a different car?

 

It's brand new and for the correct model

I had a look for any leaks but everything seemed to be put together strongly.

 

might just be a duff one mate, just take it back and ask it to be checked then switch it for another one if it is faulty.

 

I had a bailey and it made the car run really badly see post 19 of the thread below to understand what the excessive venting is doing to your engine, the jerkyness when coming off throttle is due to point number 3 of post 19! Plus I think this guy knows what he talking about

https://www.scoobynet.com/drivetrain...highlight=jolt

I know that I won't change back to a VTA, however it's all personal choice!

Damo

 

There is no problem at all with the running of the car.

Its just the noise of the DV.

What I'm trying to say is Should the DV only make a noise when I change gear? or does it do what mine is doing and makes a whistling noise all the way up to the whooosh.