How to disable your 1.6TD's blow off valve

[andy2]

This is a somewhat interesting angle for the need of a blow off valve on a TD,I've inatslled one before on a twin turbo'd dodge :wink:.

http://www.bd-power.com/ram/product.php?pn=BD%20TurboGuard&tt=ram

[vwmike]

This is a somewhat interesting angle for the need of a blow off valve on a TD,I've inatslled one before on a twin turbo'd dodge :wink:.

http://www.bd-power.com/ram/product.php?pn=BD%20TurboGuard&tt=ram

I'm still not buying into it. You let off the pedal and fuel flow drops drastically. EGT's fall, turbo slows down. As far as the turbo is concerned, the engine is just slowing down and there is no drastic difference between on and off throttle. There is no such change which would cause compressor surge.

[mk1vdub]

while I was adjusting mine to blow at just above where my boost is set to, I had it opening before I reached max boost - you do get a fairly loud 'whoosh' noise similar to a turbo'd petrol cars dump valve - but you also get a pretty silly flat spot in your acceleration as it dumps a load of air out of the intake manifold! :roll:  not exactly what you want

[VWRacer]

Andrew, I never stated, claimed nor suggested that my compressor wheel was in "bone stock" condition. But now that you mention it, even in its knackered condition that turbo made stock boost of 9-10 psi. By disconnecting the wastegate I got it up to the BOV activation range. Disabling both got me 12-13 psi.

My point remains that simply disabling the BOV on an otherwise stock engine does nothing for performance - a point confirmed by you.

BTW, I agree with your other points about changes made in isolation. Most do no good and many can make things worse. As we all eventually learn, engines are an integrated whole. Making random changes to isolated bits rarely has the desired effect...  :wink:

[andy2]

This is a somewhat interesting angle for the need of a blow off valve on a TD,I've inatslled one before on a twin turbo'd dodge :wink:.

http://www.bd-power.com/ram/product.php?pn=BD%20TurboGuard&tt=ram

I'm still not buying into it. You let off the pedal and fuel flow drops drastically. EGT's fall, turbo slows down. As far as the turbo is concerned, the engine is just slowing down and there is no drastic difference between on and off throttle. There is no such change which would cause compressor surge.

I agree that a VW TD for that matter does not need a BOV.I just wanted to show you guys that they have been used on a diesel.This option seems Ok with with the use of an automatic transmission.With the automatic  when you back off on the Go petal real quick with the Torque convertor  unlocked under full load conditions (high HP) the engine returns to idle almost instantly causing the turbo(s) to spool down quicker than they would like to which can possibly cause the compressor wheel to fly apart or even the shaft to break.I've never actually seen or even heard of any such explosions before so It's likely not needed anyways :roll:      

A little off topic but somewhat related :oops:.

[Earwig225]

Can't a person buy a modded Blow Of Valve that is set at a higher level? What would be a decent max PSI?

What about the blowoff valves that make noise when they blow off?

[RabbitJockey]

my wastegate is stuck shut, and when i first put my td in my jetta, i would always get to 12 psi and then boom acceleration was gone, i had actually made threads about how my old engine could rev better, but really it was just that the blow off valve was creating a dead spot in acceleration, so a car with a wastegate set below the bov's release pressure would actually be faster, kinda like how my friends vr4 is faster at 13psi than 14 psi because he has fuel cut off and almost blew his motor with the gtech and too much boost. haha that car only ran a 14.1, after running a bunch of mid 14's, that's hillfolk territory

[zagarus]

alright now that i have increased fuel and have a boost controller, im thinking diasbling the BOV so i can run say 15-17psi is an ok thing?  no intercooler or exhaust or EGT gauge...YET.  but intercooler should be this week, already have my muffler, just gotta save some money so i can goto PP for that.

[RabbitJockey]

it only takes like 10 minutes to disable it....  not a major step or anything

[zagarus]

sounds good to me. what would you suggest, stiffer spring, or allen bolt?

[zagarus]

alright so im gonna keep it at 15psi until i get my intercooler this week.  Sound safe?

[935racer]

15 psi is totally fine with no intercooler.

[zagarus]

oh and dave, i stil wanna get my exhaust system done, but im not sure if its completely affordable for me right now. I mean i do have enough money, but im wondering if theres anything i can do to prep thatll make it cheaper, and plus i could only come down on weekends,  but i doubt you're open sundays.

[935racer]

I can do the exhaust on the weekend if necessary. The downpipe is the trickiest thing to make, I would say you should buy a downpipe than just get whoever is installing your intercooler to make the rest of the exhaust.

[zagarus]

im thinking that will be the case. But mandrel bent, they dont do.   they can weld all the pieces so it isnt crush bent.