The not so great Forge Splitter question

J Eyo

Polo GTI (6) R
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Fitted a forge splitter valve about a month ago. Went in fine, no errors, no problems and a great sound. BUT the setting out of the box for a stock 1.8t 225 is 15ish clicks, here it holds pressure ok, but rattles, to get rid of the rattle I need to tighten it to around 22-25 clicks, but then I drastically loose boost; absolutely no kick in the face feeling. BUT, around 7-8 from 0 clicks it rattles like crazy but when the turbo kicks in, its absolutely insane, the car has never behaved like this. It really feels like I've shaved half a second off the 0-100 time and I get a proper pinned to the seat, kicked in the face feeling. However, this setting seems far too low? Will it cause any adverse effects? Ive heard over tightening it say 30-35 clicks on stock can cause the turbo to struggle (and the higher I go, the less the splitter rattles) but, the higher my clicks go, the less boost I seem to get? This feels like it is incorrect? I don't mind running with the splitter at 7-8 clicks, rattling and getting a ridiculous amount of boost, as long as I know it wont damage anything, and that this seems right?
 
First off... use paragraphs as your post is difficult to read...

Second... bin the split-r off as its rubbish.... fit a new OE valve or if you need bling a Forge 007 or 008

<tuffty/>
 
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First off, no, your illiteracy and reading difficulties are none of my business. Secondly, please, no **** heads and useless responses. Valve runs perfectly, best upgrade so far. Again, anyone with experience regarding these valves please reply with results and the setting of how many clicks and the running of these. (Also the effect of the spring tension in regards to clockwise and anti clockwise rotation)
 
Maty you will lose the ability to post with responses like that.
 
....and those who reply with utterly useless comments that answer absolutely nothing of the original question don't lose theirs.....?
 
First off, no, your illiteracy and reading difficulties are none of my business. Secondly, please, no **** heads and useless responses. Valve runs perfectly, best upgrade so far. Again, anyone with experience regarding these valves please reply with results and the setting of how many clicks and the running of these. (Also the effect of the spring tension in regards to clockwise and anti clockwise rotation)

Ok... maybe I should elaborate a little...

Firstly...
http://www.audi-sport.net/vb/a3-s3-forum-8l-chassis/34463-use-english-language-please-read.html

Secondly... the split-r is a leaky valve... FACT!... this has been tested along with other valves including 007/008 and supersize valves as well as other brands...

Any form of atmos valve on ME7 causes running issues in varying degrees as they are designed to run a closed air system... this is why they fit recirc valves... the air in the system is metered (MAF) and the ECU fuels accordingly... leaking air to atmos (lets face it this is all the split-r can do as its both a crap atmos valve and a crap recirc valve) means the fuelling the ecu has prepared will be too rich when you are back on the throttle... this is compensated to a degree depending on how you are driving and if the ecu is narrow band or wideband but over rich fuelling in between changes (when the charge air is 'dumped') can lead to multiple misfires and erratic idle etc...

Atmos valves are just not a good match on std engine management... split-r's are just a crappy leaky valve that are no good at being anything other than an air leak...

Is this an eloquently useful response for you?

EDIT... just reading back some of your thread...
http://www.audi-sport.net/vb/a3-s3-forum-8l-chassis/206718-rota-grids-sorted-but-idle-problems.html

Idle problems are fairly typical with setups using split-r's... have seen a few of these and swapped out the valve for OE... idle issues go away... I'd check your fuel trims using VCDS too... they should indicate if you potentially have an airleak as the trims will be compensating for this...

<tuffty/>
 
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Some say the best setting is 5-6 clicks if you can live with rattling, that way you get the kick in the pants feeling every time - winning!
 
Not really? I read and knew all this months ago, I wasn't really asking about problems with the valve or the running of our circ system (I had all this information available through google months before I made the purchase? Just like you had with your wonderful little English language link there) my valve and system runs fine, no vag com codes, no fuel consumption changes etc. I'm not experiencing any problems. My question was about the setting of it? (From someone who has one in and running) Scullies gets it
 
Doesn't matter how many 'clicks' you have. It's crap at 1 click, it's crap at 30 clicks.

You cannot change your boost levels with a dv, all you are doing is struggling to meet the requested level by creating a leak.....

Me7 hates air leaks, the split-r valve is an air leak.....
 
First off, no, your illiteracy and reading difficulties are none of my business. Secondly, please, no **** heads and useless responses. Valve runs perfectly, best upgrade so far. Again, anyone with experience regarding these valves please reply with results and the setting of how many clicks and the running of these. (Also the effect of the spring tension in regards to clockwise and anti clockwise rotation)

When I first joined the Audi scene some 5-6 years ago with my S3 I ran with a forge Split-R for about a year and a half. It was the most expensive DV at the time so naturally I purchased it because I assumed it would be the best and even took it to a garage to get 'tuned' properly to how many clicks it needed got the best blow off sound.

The only mod I had for that year and a half was a Forge Split-R and a green cotton panel filter, no remap and no fault coders from a VCDS scan. Never took any logs as I didn't have any faults appear or lights on the dash and it all ran sweet.

Now the only reason I changed from the Split-R was because my engine ended up getting extremely hot (somehow?miss fuelling?) and the tip of the spark plug melted and decided to bounce around in my engine so back to OEM it went. Needless to say that was an expensive full bill that included, turbo, clutch, full OEM rebuild and obviously a brand new standard DV. Now since the engine rebuild I've only run an OEM DV or forge 007P. For the last 3-4 years and 50k miles I haven't had any issues.

That's all I have to say on that really....whether it was the DV? Panel air filter? Or some other hidden problem that didn't throw up a fault code I'll let you decide.
 
Matey may I suggest that if you don't listen to tuffty that you go to another forum, the guy hasn't got 14,000 post for nothing, he is one of the most knowledgeable blokes on this forum.

I don't want to start a row just trying to stop this before it gets worse.
 
Then I would have thought his ability to actually answer the original question then would be much greater? The problem I have been having is exactly what's happening here. When asked, how many clicks do you have, how many should I set it to, what's your pressure holding at etc all ppl are hit with is, buy another or change it, again, it's not actually answering the question. I find this the hardest thing in the mod world, ask one question get 100 replies not relevant to :/ I thought this being such a reputable forum I would actually be given answers relevant, not full responses full of this is better over that bias that again, doesn't answer the question! Kwis can you at least tell me how many clicks you were tuned to???
 
Did you fail to read that it severely outperforms the oem dv? So everyone here bar literally 1 persons response is utterly useless, 7clicks it is
 
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The valve is performing perfectly and I will not be changing it. Perhaps I should delete this thread and change it to; for those currently running one?
 
No I don't remember and if you read the instructions from Forge about the tuning of the dump valve you will realise that each car has a different 'click' required which is why no one can give you an answer as it doesn't matter what they did- it's dependent upon your car and how it responds.

It's about 2 paragraphs long and I haven't got the time to copy it all, but as you're so good at google and researching about this valve I'm sure you already have this information?

If so you question is pointless - if not and you don't have the fitting and info sheet from forge I'll upload it this evening for you to read how it should be set at the right click
 
If I was you maty I'd pay attention to tuffty. What that fella doesn't know about 1.8T's you could write on a stamp. But if you want to use the splitter valve... Uploadfromtaptalk1390126537614
 
I have read the setup and have read (literally) everything on this car, the parts for it, the effects, the modifications, Google makes this very easy, and negates the need for all these comments? These responses come from people that believe they have access to google and no one else does? I may need to rephrase my initial post and that is I wanted guidance and setting advice from people currently running this splitter and no one else (on a stock 225). If tuffy had actually answered my question and not paraphrased what I have read 100 times already maybe, but now, no. Forge require 15 clicks on a stock 225, I think I mentioned this in my first post?
 
Use google dictionary to understand the instructions fully then if you can't get your head round it.

You won't get any true answer you need because it's a different setting for every car it's applied to
 
The splitter runs at roughly 90%recirc 10% atmo, you all knew this already?
 
All I've found is. 225 requires between 15-16 stock or start from 10 and adjust upwards until rattling diminishes. I want real world comments, from people using them right now
 
But no one is using them because they are ****e..
 
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Then I would have thought his ability to actually answer the original question then would be much greater? The problem I have been having is exactly what's happening here. When asked, how many clicks do you have, how many should I set it to, what's your pressure holding at etc all ppl are hit with is, buy another or change it, again, it's not actually answering the question. I find this the hardest thing in the mod world, ask one question get 100 replies not relevant to :/ I thought this being such a reputable forum I would actually be given answers relevant, not full responses full of this is better over that bias that again, doesn't answer the question! Kwis can you at least tell me how many clicks you were tuned to???

My answer was relevant I'm afraid... I couldn't tell you how many clicks makes a crap valve less crap hence suggesting binning it...

As Ben has also said... it doesn't matter how many clicks you use it at it will still leak and it does NOT outperform and OE valve... this is proven... the vent holes on the split-r are smaller than OE... when running more than stock boost you end up with a smaller hole to vent excess pressure than an OE valve... the whole purpose of a 'dump' valve is to release pressure in the charge air system quickly and effectively to prevent compressor stall and subsequent damage to the turbo (it will snap the shaft on these little turbo's)

While I could have been less short with my reply the advice still stands... change it to a new OE or Forge 007/008 but bin off the spilt-r

The fact you suggest you lose boost when you tighten it which it will only do if it is leaking.... (spotting a theme here)...

A valves operation is simple... its shut under boost and open when it sees vacuum... if its shut it shouldn't leak as this will let charge air back into the intake and not into the engine...

The split-r's adjustability is to set it between recirc and atmos operation... if you suddenly have all the boost and its performing better than expected then you most likely have another issue (like your iffy idle)... the advice in cases like this is to revert to a known working state (in your case a DV that actually works) and diagnose from there... the split-r will only reduce performance not enhance it...

<tuffty/>
 
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The splitter runs at roughly 90%recirc 10% atmo, you all knew this already?

You do realise the Split-R is about as leaky as a siv?

So those figures if true are regardless
 
Im getting full boost, regards to Quattro motors, my tuners, the splitters adjustment is NOT an adjustment for atmo and recirc. The splitter can peak at 17% atmo from manufacture but standard amount is 10%, this is non adjustable.
 
the adjustment is to keep an even spring rate to increasing bhp output. They are designed for tuners to be able to change spring rate on the fly without needing to disassemble and reassemble dv's.
 
also need to add, response is much, much better than oem so will definitely not being changing. I think the leaking rumors come from the splitter being open at idle? All dv's are open at idle due to vacuum on the dv vac pipe, only when boost starts being produced does the valve start to close.
Some valves have springs inside them which keep it closed at idle, but even theses start to open at part throttle again due to vacuum.(the n249 delete caused that but so so mildly it was barely noticeable)
 
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How about you don't be such a disrespectful moron right off the bat!

You post about PROBLEMS you illiterate ****, then complain at the advice given!

They don't work properly... CLEARLY demonstrated by you.
They're not compatible with these cars.
If you want the sound of your mum sucking on every gear change **** off to the supra forum and buy a hks ssqv.



Who the **** breads these people!!???
 
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it is 100% compatible and works 100% how it should be thank you karl? Perhaps Karl, I was lucky enough to get one that wasn't faulty. Illiterate? Its amazing that everyone seems to be a literature professor these days :D And Karl, I didn't post about problems? And I quote: "Fitted a forge splitter valve about a month ago. Went in fine, no errors, no problems and a great sound...."
 
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You posted about you're idle, which is more than likely caused by the splitter valve.. Kwistof posted about what happened to his car. Keep running it mate. Just don't come back here when you've melted your plug tips and they've ****ed the head.
 
the idle improved its hunting a lot since the new valve went in. Swings went from 800 to 1500, to 800-900? Also, how did I redefine how a DV works? How does a DV work?
 
the adjustment is to keep an even spring rate to increasing bhp output. They are designed for tuners to be able to change spring rate on the fly without needing to disassemble and reassemble dv's.

No they are not...

The adjustment is to transition between recirc and atmos... the only affect they have on BHP is to drop it when its leaks... I have no idea where you are getting your info from but its incorrect...

The whole spring thing with Forge valves is a misnomer too... all the spring does is act as a return spring... OE valves have been tested to hold over 30psi... this is because the pressure equalises in front of and behind the piston under boost... only a reasonable amount of spring tension is required to 'assist'

A closed valve is a closed valve... it has NO influence on power if its closed only if it leaks as it cannot seal properly or is an inherently leaky valve like the split-r

<tuffty/>
 
Again the adjustment is not for atmo to recirc from discussions with forge themselves, if you believe this then you have modified your valve in someway. "This is achieved by using a unique single, conical, progressive rate spring that can allow for the retention of boost pressure over a wide adjustment range. This unique spring design also allows for unrestricted piston travel and flow volume regardless of the amount of pre-load adjustment added to the spring". Under load a DV has equal boost pressure at both sides of the piston, but the reason the DV closes and remains closed under boost is because the surface area of the top of the piston is greater than the bottom, the piston is pushed down and seals off the exhaust port. The spring serves two purposes (in my case the adjustable spring stated above) the DV's opening and closing pressures.
 
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Great bit of info: The theoretical maximum that the FMDVSPLTR can vent to atmosphere would be just a few thousandths of a percent over 17%. Real world will be closer to 10%. The amount of air in the intake tract post turbo and pre throttle body once the throttle plate is closed is trivial.

Consider that whilst under full throttle that volume is pressurized to whatever maximum boost pressure you run, say 20 psi, and held there despite the "leak" that is the engine's consumption of air. Imagine 1.8 liters of volume pressurized to 20 psi several thousand times per minute WITHOUT a drop in pressure in the supply line.

Now when the throttle plate closes and exhaust energy all but disappears at the turbine the air left in the intake tract is minimal in volume comparatively. Venting all of it will result in a measurable hit to the AF ratio, but just under 20% or so is within the parameters of the ECU to cope with. VAG-Com logs of a car with a recirc DV and the FMDVSPLTR will be identical, provided that the spring is properly adjusted.

Patrick Robles
Forge Motorsport

I should have asked, any engineers here?
 
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First person I've ever seen on this message board with a negative reputation, congratulations!
Split-R is crap, and had been proven many times. Even the early 007p valves were leaky and generally poor.
If you cannot accept it then fair enough but nobody here is going to give you much advice on these valves because we don't run them
 
Forge ain't going to admit that there own expensive product is garbage, they sell it to morons that will belive everything they say.

I got a pen here which is made out of solid plastic, want to buy it off me? It'll add 30bhp to your car
 

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