Blow Off Valves?
 

I am planning mods ahead before my 40d arrives in Jan. For the performance mods I planned an AC SCHNITZER exhaust, ECU re-map, SprintBooster V3, Big Break kit (I will wait until my current ones ware out a bit) and maybe filters, and later on look into an intercooler upgrade. I have also looked around for BOVs (Blow Off Valves) but haven't found any info on it. They are talked about on the Cayenne TT forums (I have an 03) and I've heard some good feedback.

Anyone done this to an X5 T or TT? (petrol or diesel)

Thanks :thumbup:

must be nice not to worry about warranties...

:)

I can't imagine a sprint booster being considered a performance mod. It is a gas pedal mod, not a performance mod. If you want to change the pedal action, great.

A blow off valve? Seriously? If I heard one on the street I wouldn't be able to prevent myself laughing. I looked it up to see who was selling BOVs for BMW models and saw an advertisement that stated "has the ever-popular whoosh sound". Honestly. OK. Do what you like, it is your car.

Well, Sprint Booster might not be a performance mod, but it changes the performance of the car. It feels a lot more aggressive, and makes more of a difference to the feel of the car than any other mod. Besides, V3 has 3 settings: Off - Sport - Race.

As for the blow-off valves, I'm not looking for one to achieve that cheesy whoosh sound, I'm not a Honda kid :) I more interested in the performance, and I've heard some good feedback from other BMW forums.

:iagree:

I"m going to apologize in advance for this post, but blow off valves and sprint boosters are a waste IMO.

but that being said, my name isn't on the registration and i'm not making the payments so do what you want, it's your car. However, don't be surprised when people point and laugh as you drive by....

Sprintbooster... :rofl:.. from their own website:

• Sprint Booster does not increase Horsepower.

• Sprint Booster does not reduce your 0-60mph times.

• Sprint Booster DOES make your car 'FEEL' faster. (a good car wash and detailing makes my car feel faster too ;))

• Sprint Booster is not for everyone.


I think you forgot to get a tornado air too.

http://tornadoair.com/images/products/ki_unit200.jpg

It doesn't change the performance of the car, it changes the performance of the gas pedal. Calling it a performance mod is like calling a chrome gas pedal a performance mod. I do agree it can make the throttle feel different (in the same way as the BMW adaptive throttle settings do). It is just that that isn't performance per se, it is feel.

But if it feels good, do it.

I can imagine two performance impacts. The first is if you end up confusing the engine electronics because of the DME not accounting for the air that was released, and thus reducing performance. The second is with big turbochargers and wanting to maintain transient response after lifting the throttle (race cars). I can't imagine that mattering with the multiple, staged, turbochargers BMW is using to improve throttle response.

There is a potential non-performance benefit associated with replacing a weaker component on the vehicle with a more robust aftermarket valve. That is a durabilty issue, not a performance issue. Wouldn't think that changing out new parts during the warranty period (thus giving up the benefit of your warranty on the impacted parts) would be much of a benefit.

I wanted to write "If you are serious about mods, find a real tuner (not an 'installer') and ENGINEER a total package: Intake, exhaust manifolds (drop the cats? new pipe), exhaust that captures the upgrade to the manifold, serious DME programming (change the throttle mapping to achieve the sprint booster effect), more efficient intercoolers, etc, etc..."

But I didnt, as my read was this is not a serious player ...I could be wrong, but to REALLY change performance takes time, skill and $$$

Skip bovs or diverters (IMO, a joke unless you go to way larger turbos and the current bypass is ineffective). These engines ARE moddable, but DIY bolt ons arent significant.



And I have zero doubt there are people singing the praises of BOVs on forums all over- as there are many people saying air filters give them dramatically more HP. In fact, is there ANY mod that people buy and say "Ah, yeah, that didnt really work".

Nope.

A

PS Sprintbooster may be a perfect product- makes people THINK the car is stronger but actually makes no real changes other that reducing gas mileage.

I have SprintBooster on my cayenne and I love it! Everyone who has tried it does. It helps drastically when overtaking, and I did not notice a drastic change in gas milage. Especially with the V3, when driving through town, I switch it off, so gas milage is not affected.

As for air filters, I have an AP intake on my cayenne, and the difference in performance can definitely be felt. But I haven't heard of anyone changing their filters on an X5 d, so thats why they are a maybe.

I've found this to provide an effective performance boost:

http://t3.gstatic.com/images?q=tbn:A...grPiwuUtyNDn2w

Sorry, I just couldn't resist... :D

Oh, now you're talking clip on mods?!?!?

If that makes you laugh, then you should listen to an X5M. It has loud BOVs.

They may sound silly, but they do make a difference. The reason that certain ones make noise is that they hold and release boost better. The BOVs on the 50i don't hold as much boost, so they don't make a funny sound when the boost is released...that fits for a less extreme car. For the more performance-focused M they used different BOVs because of higher boost levels...hence the characteristic "cooing" sound. For someone with a tuned 50i making more boost, upgrading the BOVs would likely make a noticeable difference, as the stock 50i valves aren't meant to handle that level of boost without leaking.

Apparently not loud enough.

http://www.xoutpost.com/bmw-sav-foru...bovs-x5ms.html

The ones that sound laughable IMO are the ones that vent to atmosphere instead of the exhaust.

Reading this thread is a little confusing to help clear a couple things up. There are two types of blow off valves (BOV) either vent to atmosphere or air recirculated pre-turbo, a by pass valve (BPV) is typically on a roots or eaton style supercharger and is not the same as it allows air to bypass the supercharger when in vacuume.
It's a horrible idea to vent to atmosphere on a MAF system because the ECU has accounted for that air and added additional fuel for it then when you vent the air the AFR goes rich and can cause hesitation. As everyone pointed out it also sounds foolish. Down pipes are a great way to get more of the turbo Spool or "whistle" in my opinion that is the turbo sound that I was to hear. Another this is hard intake pipes with a cone air filter (cold air intake) will also give the OEM re-circ BOV a louder sound as will an aftermarket re-circ valve i havent taken a look to see what kind of valve it is but typically OEMs use a Bosh valve and Samco and Go Fast Bits make direct bolt on replacments for bosh valves they wont hurt your performance and will be slightly louder if that's what you dream about.

For some reason, I actually could see/hear ard getting pissed about that. Obviously he wasn't, but still, the thought was funny. :thumbup:

Diesel mods..
 

I transformed my diesel X by having the ECU remaped and modified the exhaust to relieve back pressure, also removed the heavy sock off the air filter. End result 203kw (276 HP ) 615nm (452 fp torque ) more than enough for the lighter E53. The company that organised the remap on my car through a German tuner told me for a 40d, a stage 2 tune will achieve 280 kw (380 hp ) 740 nm ( 544 fpt ) with that tune your vehicle would be a rocket ship, then an exhaust mod and your away. My X has been extensivley modified with suspension, wheels, big brake kit, flares, spoilers, etc, all of the changes have been carefully thought out, and all have delivered a good end result. Their too nice a vehicle to mess up. Just my thoughts. ;)

Yea, those are the figures I heard :) I just need to find a shop in London that can achieve this kind of HP gain with the ECU, and I'm still deciding on the exhaust.

Remap
 

Try POWERS 1 on the Forum, I haven't spoken to him for a while, I'm sure he is still around, he knows his craft well. I've been assured these figures are a safe acheivement. The 40d has had extensive engine upgrades over the 3.0d. Good luck with it.

Does Sal with Evolve Automotive work on diesels? They are in your neck of the world, AND Id trust them to do anything....

Yes, they are not far from me, about a 30 min drive. What do they do other than ECUs?