i have been reading fitting after market dump valves will mess the fueling up what about hybrid dump valves ? is there any way of having them with out messing up the fueling ? i know you dont need them for a 400bhp car but have to admiit i love the sound plus the car isnt a daily driver so willl only be used weeks ends if that

i have been reading fitting after market dump valves will mess the fueling up what about hybrid dump valves ? is there any way of having them with out messing up the fueling ? i know you dont need them for a 400bhp car but have to admiit i love the sound plus the car isnt a daily driver so willl only be used weeks ends if that

 

on an auto stick with the OEM recirc valves as there is no benefit at all plus you would not hear blow off valves anyway due to the seamless gear changes

It doesn't really do much harm, but they are pretty pointless and they dump the metered air that the ECU works out the fuel/air mix with. Some do and some don't notice momentary hesitation and poor running. The only way you can get these things to actually 'work' with the engine is to have them fitted to a car with full management.

 

I personally wouldn't entertain them what so ever.

I really like dump valve. Vvvvrrrrrooooommmm - ppppsssssshhhhhhh (dump valve sound obviously lol)

 

My revs sometimes drop off if I really give it some then dump the clutch for long enough.

on an auto stick with the OEM recirc valves as there is no benefit at all plus you would not hear blow off valves anyway due to the seamless gear changes[/Q

you would hear them tho when you did lay of the throttle. what about the hybrid ones that only dump half to atmos?

on an auto stick with the OEM recirc valves as there is no benefit at all plus you would not hear blow off valves anyway due to the seamless gear changes[/Q

you would hear them tho when you did lay of the throttle. what about the hybrid ones that only dump half to atmos?

 

Iff your reving its tits off in your drive then you will get a hint as its very hard to spool these tubs up standing still...On the road in an auto trying for a whoosh...forget mate.

 

Iff your reving its tits off in your drive then you will get a hint as its very hard to spool these tubs up standing still...On the road in an auto trying for a whoosh...forget mate.

rite ok then will leave that one alone .we need to meet up i have some many things to ask you about the car

rite ok then will leave that one alone .we need to meet up i have some many things to ask you about the car

 

Ile give you a bell in next couple days and arrange to meet up..could bring my zed to your gaff for a cuppa one night;)

ye sound ok am only in upton were you from? i see a black 300zx today in moreton big wing on the back of it wasnt you was it ?

I've got dump valves on my auto, fair enough you don't hear them when its changing up but when you have let off the power you can hear them clear as day.

I've got dump valves on my auto, fair enough you don't hear them when its changing up but when you have let off the power you can hear them clear as day.

 

Indeed. I don't run any at all and it chatters like a good 'un when I lift.

Not picked up on the use of Dump valves being ineffective before, but understood them to help keep the turbos spooling between gears, is the concensus then that they are show not go and affect an engines perforamcne rather than enhance it?

 

Had mine with the car, seemed a bit Quattroish! and the lad loves them, so they have stayed, but if thats a negative? then there gone!

from what i was reading thay can make the car run rich i love the sound but am not doin it now

 

Iff your reving its tits off in your drive then you will get a hint as its very hard to spool these tubs up standing still...On the road in an auto trying for a whoosh...forget mate.

Um my auto came with dump valves when I bought it , you can hear them it does it on lift off.tbh I'm in two minds about them but it does help with the boy racers when they sit on my ass and I accelerate and lift off, then they know to piss off cause they don't have a chance lol

that would be nuff for me just when i let of the gas. but if its messes fueling up am not going to bother unless there is a way round that

that would be nuff for me just when i let of the gas. but if its messes fueling up am not going to bother unless there is a way round that

 

remap is a way round it :)

It only causes a brief over fuel between boosted gear changes. The car comes with dumps from factory, they are just recirculating ones rather than astmospheric ones therefore silent. The advantage of the stock ones is that they help to keep the turbos spooling during gear change.

In the real world you are unlikely to notice any side effects negative or positive.

Edited July 15, 201312 yr by Stephen

so if i have a autobox would it then only over fuel when i lift of as there would be a seemless gear change

Correct, the auto changes smooth and fast and they don't vent during its changes. Only when you go from open the closing throttling.

Why you would not want to install BOV's on a engine with a MAF sensor:

 

http://www.twinturbo.net/net/viewmsg.aspx?forum=general&msg_id=2421113

 

-Andrew

Edited July 16, 201312 yr by AndrewG

Mine has recirc valves and if I have the roof off I van hear that it still sneezes a bit when I change gear or lift from boost. A nice "K-tshhhh" noise.

Why you would not want to install BOV's on a engine with a MAF sensor:

 

http://www.twinturbo.net/net/viewmsg.aspx?forum=general&msg_id=2421113

 

-Andrew

i was reading this the other day so seems a bit of a mix of some say ok and some not

look at this for turbos cars with metered airflow management

http://www.forgemotorsport.co.uk/content.asp?inc=product&product=FMDVSPLTR

i was reading this the other day so seems a bit of a mix of some say ok and some not

 

having read that, you would need a hell of a lot more fuel to give bore wash and damage your rings, may as well not install the revbee limiter if that's the case, as the rev bee, retards the spark and just floods the chamber with fuel by firing the injectors still, but it does in a way so as to promote fuel ignition down the exhaust, hence flames and the loud popping associated with it, that would be more damaging to your engine than a BOV.

intresting yes i see your point. but the splitter valve does both so you would still get some air and some blow off this may work well i take it forge know what there doing ?

intresting yes i see your point. but the splitter valve does both so you would still get some air and some blow off this may work well i take it forge know what there doing ?

 

They make duel piston dump valves, designed specifically for cars with MAF's, in all honesty its a mine field of arguments for and against, im yet to see a car damaged from the use of BOV's

 

I have z1 motorsports Dump valves on mine, they make a bloody loud pssssht noise, the car doesn't die when its set up correctly (idle and what not), i did have a set that were not designed to work with a MAF and that used to make the car cut out when coming off hard throttle, if you put your foot straight on the clutch.

 

I dont mind the OEM recircs, but i had a issue at one point with the annoying goose honk (where the diaphragm inside was giving way, so on hard boost you would hear what sounded like a goose honking lol) so changed over to dump to atmos.