Dump Valve Problem?

[SnowMold]

Hello, yes its me again lol. Got another slight problem. i know this was touched on a nother old post but thort better to explain it properly rather than drag an old one up. I have an evo 8 and im currently running with an HKS SSQV V3 dump valve (atmospheric). im having the problem of the car dropping the revs of cutting out all together when ever i come to a stop, Ie at traffic lights or junctions. becoming very anoying, heard it migth be the dump valve messing with the MAF sensor, is this true? if so is it a recirculating dump valve that al need? could anyone recommend one? al probs be getting this sorted tmw if so.

Thanls again, Rob

 

[frankie2531]

my mate had that dump valve on his evo and had the same prob and changed for a re cirulation type and the problem went away hope this helps mate.

 

[DennisEvo]

I've had this problem,I've got a turbo smart bov,£250,u can set it up as either a re-circulating or normal,if u set it as normal u can actualy adjust the setting to eliminate the prob,u simply twist the top one way to make it harder the other way to make it softer,mine still does it now n then,but only if I floor it n then have to slam all on straight away,jus needs another slight tweak.the lads are based in normington near me but they will post,they sell loads of performance parts,intercoolers ect.hope this helps

 

[SnowMold]

thanks for the response guys, al get a new one sorted tmw. much appreciated!

 

[ElDopesta]

Having a nice doosh on gear changes might be pleasing to your ego's ears but it is like a minor suffocation to your engine

You would need to have a map to sort the problem out but why put your engine under that sort of strain and get smoked by lesser cars just because of it

I cannot understand why people prefer atmospheric over recirculation??? It goes against all the money you spend on mods to make the car go faster

When will people learn that

Any way, about to have my coffee now so my replies should be a little less twingey on the other threads


El

 

[SnowMold]

I understand where your coming from El, but it was alrdy on the car when i bought it. any way i have ordered a fully re-circulating dump valve with a built on boost adjuster. should be fitted in the nxt couple of days.

 

[ElDopesta]

Built in boost adjuster.....................sweet!!!!

You WILL feel difference right away.

El

 

[fingers]

what make is that? how much did it cost, i want one!!!!!

 

[SnowMold]

Forge i think, costing me £210 including fitting i think the bloke in the shop recommended it if am gunna tune me engine so i thort why not. al see if i can find a pic


Type RS Piston Valve - Recirculating.

 

[fingers]

thanks fella.

 

[sponners]

you can buy a kit to convert the hks valve into recirculating.......its about £15.

I dont think the v3 ssqv is adjustable??? if it is then you could try raising the spring pressure on it.


......dont understand the comments why a vta dump valve will make the car less powerfull or put the engine under more strain

 

[ElDopesta]

Well first of all, the ECU is set to take in a certain amount of CO2 which it does on throttle or whilst on idle. When it come to gear change, it is programmed to allow a certain amount to be inducted which has been pre calculated and set in order to allow the remaining amount to enter via the blow off from the recirculating valve.

Now if that valve is atmospheric, then the amount that has been calculated is wrong and the engine is getting an insufficient amount of CO2. It is due to this reason that the engine will not perform as it has been designed to. If the engine is not performing the way it is designed to then it affects the over all performance and creates a small amount of strain as the way the car is being driven will need to be adjusted by implementing a lead foot even though it is not required.

It also affects the spooling of the turbo which is the reason the dump valve was introduced in the first place although not directly.

Not similar or too far off from the hot air prognosis of the stand alone cone filter.

The way to compensate for this will be by re mapping it or reverting back to a recirculator as I have mentioned right here.

A simple test can be made by popping an atmospheric valve onto the car and driving hard through the gears for a couple of minutes followed by an emergency brake. Then, immediately, by replacing it with a stock item and doing the same thing again. The difference can be felt right away.

El

 

[SnowMold]

I love you guys!

 

[sponners]

yeah the ecu will fuel for x amount of airflow, and when a vta dumps then the ecu will still fuel for this lost air.....hence funny idle or even stalling at juctions etc.

but when your using the power/accelerating then the valve is closed so the fuelling is correct.....so therefore wont affect the power output whatsoever.

also the valve wont affect the spoolup time either (unless its leaking)


ps......I find for even better spoolup times your better off without a dump valve.

 

[ElDopesta]

I agree with this Sponners, kind of, the fact remains however that the dump valve is designed to be initiated during gear change so if the valve leaks and is closed during normal driving then it is besides the point altogether as that is not it's point of function.

Power out put is not only related to when the car is under hard throttle, it is affected by changes in gear too which is the point of acceleration/momentum that is under the most scrutiny.

I did not say that it affects the spool up time, I merely pointed out the fact that it affects the spooling, again, it is designed to keep the turbo spooling on gear changes, if it does a poor job at that then it is not functioning properly. The majority of atmospheric blow off's require the intake pipe leading to the induction pipe to be blocked off. where does their venting go to in such cases????? Not where it is supposed to, that's for sure!!

Funny idle and stalling is the reason this thread was started by SnowMold if I remember correctly.

El

 

[SnowMold]

Yeah, we need a 'thumbs up' smiley for sure!

 

[SnowMold]

getting the dumpy fitted on wednesday afternoon, FINALLY! forge apparantly had a problem of finding the right parts for me. this is a dual piston re-circ im getting fitted, not a single. i'll keep you posted to see if it has sorted the problem on wednesday

 

[wriggs1210]

I've had this problem,I've got a turbo smart bov,£250,u can set it up as either a re-circulating or normal,if u set it as normal u can actualy adjust the setting to eliminate the prob,u simply twist the top one way to make it harder the other way to make it softer,mine still does it now n then,but only if I floor it n then have to slam all on straight away,jus needs another slight tweak.the lads are based in normington near me but they will post,they sell loads of performance parts,intercoolers ect.hope this helps

what is the name of this place and where is it in normy? thanks for your time, steve.

 

[ElDopesta]

There are lesser priced valves that do the same job and are as good as turbo smart.

El

 

[wriggs1210]

thanks el. could you recommend any? and where to get them from? cheers.