Dump Valve King Thread - A discussion

Jay

Jay

Admin
Right.

Normally the first question out of a newbie's mouth - where can I get a dump valve?

For most it's just the sound that attracts buyers, a lot of guys pay big bucks for something that doesn't make the car go any faster or last longer. I personally feel the money can be spent elsewhere but it's one of the perks of owning a turbocharged car.

We'll start the topic off with the standard item. The 4EFTE is fitted with a recirculating valve that takes excess air from the system and places it back into the intake tract. I personally favour the stock setup for it's quiet operation but once boost pressure is raised the standard item can fail.

Many of us don't run any dump valve at all so I'd like them to be part of this too. There is that question of extra strain on the turbo but how have you guys fared with reliability?

Any pictures, sound clips or videos are welcome to demonstrate your setups.
 
HutchGlanzaV

HutchGlanzaV

Member +
My car was fitted with a BOV when I bought it but even if it had the stock set up i'd change it. Love the sound! WAAAAARP TISH!!!!
 
Wild

Wild

Member +
I use the standard valve and have made it dump to air instead of re-circ. It sounds fine if a littler quiet. I've also tried no DV but felt it took longer to reach full boost again, although that may be TOTALLY psycological... ;)

I'd like to buy a SSQV because it sounds nice, but I wont be spending 150+£ on it.
 
T

tr0ublemaker03

Member +
I have a HKS SSQV, it came with my engine when I bought it for my swap...

when I do my turbo upgrade, I'll be running a Tial 50mm BOV, as I'll be running higher boost....and it'll be able to evacuate the excess pressure efficiently

personally, I like the peace of mind a BOV gives...I personally belive it damages the turbo...of course so does have 2-step on the car...and I plan to have that, hahah
 
turbo-fever

turbo-fever

Member +
well i have been running mine for about 2 months with no dump valve and she seems fine at the mo, but wil put the blitz bac on soon
 
R

Rutger

Member +
i am running a sard dump valve, only got it this week, and i decided to get one because its just one of those things. if you have a turbo car a dumpvalve is too much of a temptation. the sound of a BOV is just a bit of fun for me. too be honest, that is the only thing that made me get one! the sound!! :)

Rut
 
rb69

rb69

Member +
Just running the stock re-circ valve for the time being. Getting an SSQV soon though. I'm sure when running the stock re-circ i've heard it make a bit of noise when driving hard?? I could be wrong tho!
 
R

Rutger

Member +
rb69 said:
I'm sure when running the stock re-circ i've heard it make a bit of noise when driving hard?? I could be wrong tho!
Click to expand...

ye, ive heard more folk say that, but i never heard it, mayb i am not hearing it tho, i dnt no :)

Rut
 
Dub-Se7en

Dub-Se7en

Lifer
Have run a few types, Bailey DV24, Blitz Supersound and HKS SSQV.

I liked the sound of the bailey one the best, but it's weak piston alloys it to partially open when at motorway speeds, creating an annoying wooshing sound. This doesn't affect it's performance however, as soon as you bring the car on boost, it closes.

The Blitz noise is very loud and attention grabbing, too much so for me. it is adjustable from what i can tell, have not tried it yet. it doesn't open at motorway speeds unlike the bailey one.

I borrowed the HKS SSQV to try it out but didn't warm to it price and the high pitched noise it makes. can't fault it's build quality and performance though.

before the rebuild i didn't run a BOV for ages. the sound of a non bov equipped car is awesome and when i stripped the turbo off there was no signs of wear at all.

i've got videos of the bailey, blitz and no bov here
 
GTti

GTti

Member +
An effective dump valve does not operate by vaccum and would simply be a spring with a hard resistance (depending on the application). This way it can be configured (With different strength springs) to release pressure in the intake at a set level (Say 18psi if you're running 15psi).

This method will maintain pressure in the intake but also keep it under tabs by releasing pressure above 18psi (If you think high pressure is bad for your setup). A recirculation valve will work in much the same way by maintaining pressure in the intake, therefore I think it's far more efficient than the usual dump valve!

Unfortunatly most dump valves operate purely by vaccum and open fully to release all air mass. Logic and science would say this is not effective, creating a huge pressure drop by releasing intercooled(cold) air. When the throttle butterfly is opened how can response be better when all the cold compressed air has been blown into the atmosphere?

As for reliability, I have had an IHI RHB5 pushing 14psi on overboost (Every gear) and 10psi there after for 87,000 miles and almost 20 years without a dump valve or recirculation valve.

I will also not use one in my race car, gear changes are quick causing minimal 'compressor stall/surge/flutter' and I will need pressure in the intake for quick response on changes. A turbo spools at 100,000 RPM, a few PSI of air pressure is going to make minimal difference to its speed!

In a road car quiet operation is a must for regulations and customer experience, it is also illegal to vent oil and oil vapour straight into the atmoshpere with a dump valve - they have to be combusted by passing through the engine.
 
Elaine

Elaine

Lifer
I have got one but since putting on the air filter and fm I have got so many noise I am not sure I want to keep it..

Is it something you need does it really help your turbo to last longer or is just all about the noise??
 
Nwimie

Nwimie

Member +
ive got a blitz and its loud lol....
altho i might take it off for a bit and run no dv as i like the sound of compressor stall :D
 
sx_turbo

sx_turbo

Lifer
the turbo spooling sound that you get from the air filter, is brilliant, i like it when cruising down motorway, put your foot down and and hear that noise i like it
 
SupaStu

SupaStu

Member +
Jay

Just got a SARD R2D2 BOV this week and should fit today, if I can be bothered, just out of hospital and face hurts like f**k.

On the standard setup you can hear the recirc on the glanza. If you rev it hard and have the stereo off and a quiet bit of road you can hear a little whoosh. I used to notice it more on my last glanza (lightweight version, less soundproofing) that only ran on high mode turbo.

DSC00066.jpg


I'll let you know what I think once fitted as have never ran with a BOV before and my setup on the glanza is standard, apart from the suspension setup ;)

I must say that the SARD kit looks good as it comes with the full fitting kit specifically for the car, and does not have to be adapted or modified to fit.

Cheers
Stu
 
Last edited:
riko666

riko666

Member +
my Standard Dumpvalve is relatively loud, but it could be cause I have no interior...I'll be getting a GReddy Type-RS w/ the recirculation pipe, to keep onto the recirculating function....attention grabbing noise just doesn't do it for me
 
Monkfish

Monkfish

Member +
Pah, all you BOV fairies :p **Runs**

I've run without a BOV for 6 months now. I've changed 1 turbo due to the oil seals letting go. The car had done 74k which is about the life expectance of the CT9 so I'm led to believe. The thing is with turbo's is that they are subject to so many variables it is impossible to pin a failure on one thing, such as running with no BOV. Exhaust gas temperature, fuel mixture, vibration, oil contamination, oil starvation, foreign object (Stone, bird, small children etc), wategate/actuator failure, the list goes on.

I've since been running a CT9b without a BOV for about 4 months (Save for a week or two here or there for a change) without any problems thus far.

Here's a vid taken ages ago on the CT9a with just mesh on the inlet and no BOV.


:rockon:

I'm going to make an intake system with a filter behind the bumper as it sounds a bit too harsh at the moment with the CT9b (It's louder than the CT9a).
 
You must log in or register to reply here.
Top