so do they make the car run lean between changes and is this a bad thing if it does?

and if so why do companies like blitz/hks sell them then?

 

------------------

Actually they make your car run rich between shifts.

 

They let out air of the system that was already measured by the AFM.

 

 

thats what i thaught so why is it percieved that they make the car run lean.....?

The companies sell them beacuse of the high demand...

 

People typically like them for the sound, most of the gain is in the mind. A car setup like mine will run better without dump valves, although some 300s get a gain... probably the 800bhp+ ones???

i find the noise abit irretating sometimes, but needless to say i baught mine purly on the advise from a comapny i mention way to often lol(in a bad sence) they told me id better get some because these cars dont have any......!!!!1

You do have Re-circs! They're valves aren't they for Christs sake..LMAO! Thought this post was about valves...

Mine sound like a old bag-lady trumping after one too many bottles of special brew.

But I like em, not because they sound cool (which they do), but because they sound like farts.

Any car which does a fart when you change gear is cool by me, because farts are after all very funny

Glen.

 

I'm affraid I disagree about the car running either rich OR lean. When you release the accelerator the injectors cut, so how could the engine run rich???? The air that the MAS has measured would just go in the engine anyway with no fuel so there!!!

 

Please correct me if I am wrong. Maybe I am missing the point......

 

CheerZ.,

 

Andy

so therefore the car would be lean for a split second?

IMHO, the car will be neither rich, nor lean, with or without aftermarket BOV's.

 

Throttle plates are closed - therefore no (or very little) air is entering the cylinders. The ECU will switch the injectors into 'decellerate' mode (i.e. just enough fuel to prevent damage, I believe), and the engine will in fact be returning to an idle state.

 

The excess air will either go out to the atmosphere (BOVs) or go round and round in the intace tract (*before* the throttle plates) with the stock recirc valves..

the point of most bov's is to stop the turbos over spinning on release of ure heavy right foot the pressure on the turbines is reduced saving them from self destructing.....rich or lean for the amount of time in which the bov's are operating it doesn't make any diffrence. cossies defo benifit from a bov but for me the jury is still out on the 300 with it having re circ's but i have blitz ones on mine and the single benefit i saw from them straight away was after blipping the throttle my revs didnt drop to the point where the car cut out

I'm thinking of getting Blitz BOV's after I get bigger turbos (thought they'd help reduce lag between gear shifts).

Does anyone have any probs with their BOV's:- experience, not scientific theories please!

Dave

To me it seems like someone is sneezing,

so it you like the sound of sneezing you're in luck.

A cheaper way is to snif pepper, you'll get the same sound but in the car.

Tooley me old m8 - still want that computer re-loading?? Sorry about sunday - usuall hangover

 

Anyhows..... BOVs don't stop over spinning the turbos!!! When you release the lead foot, the injectors *virtually* shut off, therefore there is no combustion, therefore there is no exhaust and therefore there is no pressure to overspin the turbos .....therefore

 

The fact is the re-circulation valves do diddle squat because they are straight after the air filter - the gasses released will go back out straight through the filter The best response from BOVs is achieved by plugging the re-circs so the BOVs are the ONLY valves doing the work - scaring old grannys is more fun as well

 

CheerZ,

 

Andy

Hehehe this is funny,

I was following a twat (sorry for language but he was a first class Leo ) in a R5 GT Turbo and he had dumpski valvualation and *just HAD to* accelerate enuff up the high street to set em off, so it was;

weeeeeeeee - gearchange - tssssss blow off.

thru the traffic lights

weeeeeeeee - gearchange - tssssss blow off.

etc etc, the silly little twot nearly lamped a poor old dear trying to cross at a set of pelican lights...

weeeeeeeee - gearchange - tssssss blow off.

etc

past maccy deez

weeeeeeeee - gearchange - tssssss blow off.

next set of lights

weeeeeeeee - gearchange - tssssss blow off.

This doiley was looking at some bit of totty during his weeeeeeeee - gearchange - tssssss blow off and *SMACK*

right into the back of the car in front - no damage to the car or driver and no one hurt, but it ripped off his nosecone.

I laughed as I gave my details and when the insurance company for the car driver in front sent me an accident form to complete I had to fill it in in "weeeeeeeee - gearchange - tssssss blow off" stylee.

Plonkerer.

Glen

 

 

Glen, I agree me old mate, BOV's are for Leo's...apart from El Tooley Generale ICE God Extreme Hardcore...Viva El Tooley!!!!!!! LOL!

 

But in all non-seriousness(nothing changes!) see my previous post about said Leo Wanker in RS Turbo behind me all the way up Stevenage High St. TOSSER! Noooooo NEeeeeeeD!

 

Saw some guy in an MR2 the other night, no Turbo scrawlings on the motor but hey, you know it's a TURBO when all you can hear is...

 

Vrrrrroooommmmm.....Ttssssssssss! WTF?

 

Sorry, but I think they're wankerish! IMHO!

 

SAD MOTHERS!

 

Tim

;-)

 

Sorry guyZ but dump valves are the muttZ nutZ!!!

 

Well, I like 'em anyway

 

CheerZ,

 

Andy