[doughboy]

A bit of teabreak waffle for anyone interested:

Had the above fitted on Wednesday and had a run out this morning.

JB3 on MAP5, DVs on Yellow stiff springs.

Firstly the part throttle boost pick up is very sharp, too sharp I think, even on a tiny throttle the car is off in that kind of woooooahh way.

More importantly any more than about 20% throttle gives a slow down, i.e. the boost drops or the throttle valve is closing, then the boost re-builds again. Without logging I think the boost is overshooting its target and being backed off.

This leads me to believe that the OE divertors must be inherently bleeding boost on part throttle (note i say part throttle, at WOT the OE DVs will not bleed as there's no pressure difference between charge pipe and manifold) and the maps kind of expect this to happen. I figure at part throttle as boost builds you have a pressure difference develop across the throttle body which will partly pull/lift a lightly sprung diverter and help to regulate that part throttle pressure difference, the Forge units must NOT be doing this and the boost is just shooting straight up.

You can hear the DVs release boost on a throttle off, so they are opening, but it must be requiring a larger pressure difference to do so than OE.

I changed to MAP4 (as 5 but with lagfix OFF) and the problem has gone, much smoother and great throttle response, but tha car has lost the urgency it had with OE DVs and MAP5. Waste of time maybe?

The NOISE.

Hmmm. not too sure about the noise, at first I thought you couldn't hear it, but you can hear the woooooooosh-ppssssssshhhh through the open filters INSIDE the cabin with the windows shut and radio off, but interestingly not with the windows down.

I'm not sure if that's for me TBH, it just makes the car SOUND laggy as you can here the spool up reminding you that's its there - this kind of defeats the object with the N54 IMO. And its a BMW and i'm nearly 40 - that might be reason enough to take the cones off.

I'll go out at lunch and try the softer forge springs and give it a go on MAP5 again.

[rogerxp]

I'm surprised you've got any free time to actually work with all this 'fettling' going on . Interesting work-in-progress...

[doughboy]

I suprising how 'testing' you can do if you leave for work 1/2 an hour early and donate your lunchtimes to it too....

Just time for a scotch egg before I nip out again!

[A335i]

Glad you did this write up as these are exactly the next 2 mods I will be doing. My forge diverter valves arrived today with the DCI due to arrive any time soon.

I've heard in some instances that with the DV's fitted that part throttle does pick up, which is something I hope will happen, especially combined with the DCI, as I think that at the moment part throttle on mine is a little too unresponsive.

Perhaps with yours it may be the case that map 7 with the JB3 will work better with the yellow springs where you are boosting around 15 psi. However, obviously, with you're mods at the moment it will be unwise to switch to map 7. Hopefully, you find more success with the green springs, and when you install your other mods reverting back to the yellow will be better suited on the higher map.

Just out of interest, I do have an idea in my mind, but, what was the labour time to fit these 2 components. I think you would save on time doing both at once considering that for both you need to remove the air box?.

[335i E92]

How was the scotch egg?

What you have just described (Forge DV's) is EXECTLY the same as my experience with the yellow spring on my old DMS map. As soon as you tap the throttle you feel an instant pull and think, oh ello this feels lively. However when you give it more it seems reserved and held back, as you said possibly over boost??

I then changed to the green spring (still on the DMS map) and it then seemed very laggy (almost like it was leaking boost / spring to soft)

Anyway the car was then put back to stock with green spring and whilst under gradual acceleration it seemed less laggy when you step straight on the gas there was delay of 2-3 seconds before any boost was delivered.

After speaking to Forge they advise to put the 2 shims in each DV on the green spring. This improved things slightly but the car still hesitated like a gooden when you asked for anything quickly.

I had a new set of OEM DV's fitted 4 weeks ago, instantly problem solved.

I've sent mine back to Forge via Imran at Evolve who has also had similar problems with the new revised Forge DV's, so much so he no longer sells them.

Hopefully the green ones will work for you Mike, my guess is you will run in to the same lag as i did on the green ones.

Also Imran has never had problems with the OEM DV's even on stage 3 420bhp!

[doughboy]

Originally Posted by ajuggessur

Just out of interest, I do have an idea in my mind, but, what was the labour time to fit these 2 components. I think you would save on time doing both at once considering that for both you need to remove the air box?.

Its no more than 1 hour tops to fit the DVs and Cones. Mike at Darren Woods did it in about 15 minutes.

As you said its scuttle plate and airbox off for both anyway, then the airbox stays off.

[doughboy]

Originally Posted by 335i E92

Hopefully the green ones will work for you Mike, my guess is you will run in to the same lag as i did on the green ones.

Also Imran has never had problems with the OEM DV's even on stage 3 420bhp!

I agree, there seems to be no issue with the OE ones.

I've been out and played with the JB3 settings at lunch, turning down the Throttle Gain setting from 40 to 30 has got rid of the boost overshoot effect (if thats what it is/was).

Its now much better and more linear than it has ever been, but it still bogs if you give it WOT from a light throttle, if you increase the throttle smoothly (as I normally do any way) from light to WOT then its spot on and really hummin'

I tried Lagfix OFF too and turned the gain back up and this was very smooth and linear too, power building much more with revs than a big slug up early.


Spin

[335i E92]

I'm just not a fan of this upgrade, for me its not really required unless you are running stupidly high boost like 18+psi. Even if the OEM DV's eventually failed its only £65 for a new set.

I'm usually progressive with the throttle too, i just wasn't happy with the though that if i ever needed to move quickly to avoid a situation i might end up bogged down and up shit creek.

Maybe you'll be able to do something with the JB3 to compensate everything, just seems like a lot of drama for a £200 expense to me.

For me the imminent DP ungraded will give me all the responsiveness i need.

Ha, sorry to throw a negative, obviously i hope you find a way to make it work. Just giving you my experience and opinion.

[A335i]

Originally Posted by 335i E92

I'm just not a fan of this upgrade, for me its not really required unless you are running stupidly high boost like 18+psi.

I've had that exact same mentality for some while now and hence why it's taken me quite some time to decide to change the DV. As they say if it aint broke why fix it.

However, I got a used one at quite a good price so thought why not give it a try. I do hope it works fine for me even if it does nothing noticeable, which is what I'm hoping now as some of the comments seem to be adverse to the product, at least I know is will hold up for longer than the oem component. Just hope it isn't money wasted as I really wanted an OCC, which I know would have been a much better investment.

Doughboy - Thanks for the labour time btw and once again please shut up about Darren Woods otherwise you'll be making me want to purchase a house in sunny Stockport to save on my car bills, lol.

[335i E92]

Originally Posted by ajuggessur

I've had that exact same mentality for some while now and hence why it's taken me quite some time to decide to change the DV. As they say if it aint broke why fix it.

However, I got a used one at quite a good price so thought why not give it a try. I do hope it works fine for me even if it does nothing noticeable, which is what I'm hoping now as some of the comments seem to be adverse to the product, at least I know is will hold up for longer than the oem component. Just hope it isn't money wasted as I really wanted an OCC, which I know would have been a much better investment.

Doughboy - Thanks for the labour time btw and once again please shut up about Darren Woods otherwise you'll be making me want to purchase a house in sunny Stockport to save on my car bills, lol.

let me know how you get on with the DV's... Occ HAS to be your next mod, it's a must to combat carbon build up and ensue long term performance. Get the AR Design one and order yourself a set of thier cat**** downpipes. This will give you all the low down power you need.

Mike, any joy with the various jb3 settings?

[doughboy]

Too many chores this weekend!

Bathroom fitters coming on Monday...

[Cafe.Racer]

I don't know nuffink about the 335 - which way round are the DVs fitted? If you call the unscrewable bit with the vac hose in it the "top" is it the side outlet or bottom outlet that goes to the boost side of the turbo?

[doughboy]

Originally Posted by Cafe.Racer

I don't know nuffink about the 335 - which way round are the DVs fitted? If you call the unscrewable bit with the vac hose in it the "top" is it the side outlet or bottom outlet that goes to the boost side of the turbo?

Side inlet faces the charge (boost) pipe.

[m1bjr]

Anyone been on the dyno yet then?

[doughboy]

No - well reminded. Have you yet?

There's a good scooby / jap tuners near us (2 miles away) who have a decent dyno - I put my A3 on it a few years back.

I'm wary about places not used to BMW's using the wrong points for strapping down though.

I might give them a ring and see. http://www.prosport.ltd.uk/

[M3-FAST]

Originally Posted by doughboy

No - well reminded. Have you yet?

There's a good scooby / jap tuners near us (2 miles away) who have a decent dyno - I put my A3 on it a few years back.

I'm wary about places not used to BMW's using the wrong points for strapping down though.

I might give them a ring and see. http://www.prosport.ltd.uk/

...or dive across to CPR in Warrington - you could get the geometry done and dyno'd at the same time

[m1bjr]

I saw 311whp this w/e But I made the big error of switching a map right before the runs.
On the way out of the site I could actually feel it building with every squirt to redline.
Noticed this before though, JB3 map adaptions do take a little time to settle.
However, the operator says normal is between 350 and 400fly for JB3 on pump and a filter, so its not 'that' bad but a little disappointing (mine 374).
Bugger

I had a two hour trip home and as I left the motorway I picked up a local nutter in a newer M5.
Slipped through the bends quicker, but didnt have the brakes to match it though.
In a 1/2 mile roll from 50ish, nothing in it. I pulled over and it couldnt get by, all the way to big numbers

So my guess is it settled down at somewhat more than it was making at the rollers with no adaptations set.

[doughboy]

Picked this one back up again.... after promising to change the springs on the 19th November, I finally got round to it yesterday!

After fiddling with the JB3 it was as good as ever on the forge diverters with stiff yellow springs, but it still wouldn't run lag-fix mode without over boosting (i think) and dropping the boost off if you were heavy with the right foot. It got much smoother and more predictable after a week or so, I think the forge DVs are a little sticky when new and cause over boosting / spikes until settled in.

The yellow springs are meant for 15psi+, but on the Dyno, even on map 6, the car never exceeded 14.5psi as logged by the JB3. Anyhow, I wanted to check it with softer green springs meant for up to 15psi, so i put them in yesterday.

The effect theses things have at part throttle is so profound, much more than you would ever think.

Immediately it felt flat on map 4, much more laggy and a more gentle throttle response.

So on with map 5, (same as 4 but with lag-fix on) HOLY MOLY! It an absolute beast, the throttle response early on is just as sharp as with the yellow springs, but it doesn't drop out if you over do the throttle, it just keeps on going!

2nd gear, DTC on, from about 2krpm, a nice slug of gas to about 2/3rds and bam! off she goes, wheels spinning up, then at 4.5k it just wips into the red line as if i'd hit a patch of ice! Seriously quick.

Fast as fook! I still can't fathom why a boost divertor has such an effect on part throttle performance.

Got my AR decat downpipes now, they're getting fitted on 31st Jan.

[Em135eye]

Can anyone translate this thread for me?!

[doughboy]

Its nothing to do with diesel, land rovers or surfing.

[Em135eye]

Yes but I could steer it into LR, surfing and diesels. It's what I do

[zltm089]

Thanks for posting guys ....very interesting to see some real tuning....

yeah, a translation would be welcomed!. ..

.....