stupid question time

[Topple]

my turbo boost gauge finally turned up today.

The kit supplies a brass connector to screw into the manifold and a plastic T piece to fit into a pipe.

Where is the best place to fit one or the other ?

[Reaper]

Here is a pic of mine, it helps that I have a dump valve to tee into but you want to get it a close to the plenum as possible to get the most accurate reading.

[Topple]

intresting place to put it, never thought of that.

The instructions say on the manifold.

[Porny]

Ignore the instructions in the box....

The best place (as recommended by Land Rover) is here (see pic)

...but you want to get it a close to the plenum as possible to get the most accurate reading

Do you have a plenum on a diesel???  Intake manifold is the usual term.

It's only worth taking it from the inlet manifold if the actuator control is also taken from there.... which it is not as standard.  

Just T into the pipe from the turbo compressor housing to the actuator (which in turn has a T to the injector pump)...

A word of warning.... the T piece supplied with TIM gauges are very easy to break!!!!


Ian

[davidlandy]

Peter

what difference does the fitting of the dump valve to a tdi make?

[Porny]

what difference does the fitting of the dump valve to a tdi make?

It goes whoosh....   When you lift off the accelerator

So you have clatter, clatter, whoosh, clatter, clatter - not just clatter, clatter, clatter, clatter    


Ian

[davidlandy]

what difference does the fitting of the dump valve to a tdi make?

It goes whoosh....   When you lift off the accelerator

So you have clatter, clatter, whoosh, clatter, clatter - not just clatter, clatter, clatter, clatter    


Ian

so nothing other than the whoooossshhh then?

[Topple]

Ignore the instructions in the box....

The best place (as recommended by Land Rover) is here (see pic)

...but you want to get it a close to the plenum as possible to get the most accurate reading

Do you have a plenum on a diesel???  Intake manifold is the usual term.

It's only worth taking it from the inlet manifold if the actuator control is also taken from there.... which it is not as standard.  

Just T into the pipe from the turbo compressor housing to the actuator (which in turn has a T to the injector pump)...

A word of warning.... the T piece supplied with TIM gauges are very easy to break!!!!


Ian

Thanks Ian,

thats where I was going to put it but just wanted to make sure. It took the guy on ebaythe best part of a week to send it to me.

Do you think it's worth calibrating before I fit it, I know we discussed it earlier, if so I can get it over to you first.

P

[Landy90IOM]

am I right in thinking that diesel dump valves are actually operated with a electronic solenoid? as they dont have the throttle plate that petrols have? So where as a petrol dump valve would decrease turbo lag, aswell as the whoosh,  diesels just have the whoosh

[TimM]

I used to have a Dump-valve on my Escort RS Turbo (sits back and awaits abuse!), the idea was that if the throttle was closed (during a gear change) the backpressure from the boost going nowhere would stall the turbo, and then it would have to startup again before it could give any boost.

The Dump valve allowed the excess pressure to vent off and allowed the Turbo to keep spinning during a gear change and so as soon as you put your foot down your would be on full boost straight away, this didn't increase the maximum power (so my insureres didn't load the policy) but allowed it to stay at it's upper limits more - the car became faster and much more drivable, and it also prolongs the life of your turbo.

BUT.

I've always heard that these don't work the same on Diesel's and so have not fitted one.

I'd love them to be wrong, if I could do do my 300TDi lump what I did so many years ago to my Escort I would be very happy.

 :D

[littlepow]

My Cupra had a re-circulating dump valve, removed all lag, as when you lifted off the throttle to change gear. The unwanted boost from the turbo was fed back in to the start of the turbo, keeping it spooled up nicely. So no whooshing noise just constant turbo boost during shifting.

[Reaper]

what difference does the fitting of the dump valve to a tdi make?

As the daughter of a friend of mine said "it makes it sounds like a bus" which about sums it up!!  :lol:

[Topple]

when I got the gauge out of the box it read 0

by the time I had finished plumping it in and taking it for a spin its reading .75bar even with the engine off.

On the run it fluctuated between .75 and 1 bar

how do I zeroise it ?

[Porny]

Hrmm interesting....

Sounds bug***d to me    

Although to be slightly more helpful...

Four choices:

One phone up the importers (can't remember their name off the top of my head)... ask for a new a one because yours is faulty. To which they will happily oblige (well they did in my case - mine was way out - and the bloke didn't have a leg to stand on when I told him how I tested it!!!)

Second choice... the place you bought it from (off Eblag) phone them and tell them it's faulty and you want a replacement!!!

Third choice...

Adjustment  :twisted:

The needle, with the engine off should sit between the green and yellow lines (see pic)... if it doesn't you 'can' use a flat blade screw driver to 'adjust' the internal mechanism slightly... put the screw driver through the hole where the bulb goes, and move it fractionally until the needle is in the desired place.

Fourth option... send me a pm I may be able to get you and exchange boost gauge!!!


Other than that....
At the moment you're only getting 0.25bar of boost which seems pretty low!!!

Just check you haven't got any leaks anywhere.  Esp. check the 'T' piece my original one cracked (can get you a better replacement for a few pence if needed)


Ian

[Topple]

Took it out the dash yesterday and the needle went back to 0 (as your pic) . adjusted the turbo, didn't screw it in all the way, now on full power the gauge reads just under 1 bar.

I had a thought though and talking to others. If the engine is run with increased fuel flow and turbo boost what effect can that have on temperature and the effect of that.

I've adjusted the smoke screw by about 90 degrees, the diaphragm by about 90 degress and the star wheel by 90 degrees. and the turbo by approx .2 bar.

I don't want to cook the engine whilst towing a great big caravan.

[Porny]

More fuel = more power = higher EGT (exhaust gas temp)....

The problem with a diesel, unlike a petrol engine, is the more fuel you put in, the higher the EGT becomes and very high EGT is not good.....

However a problem will only occur if you keep your foot flat to the floor for a long time with the engine under load.... i.e pulling your caravan up a long hill on full boost.

The tweaks you have done are basically the same as my 90" when I had a 200Tdi fitted....

I regularly towed a loaded trailer without a problem... and my 90" when solo was often driven 'enthusiastically'!!!  :twisted:

One point is that you haven’t actually adjusted overall fueling, so in theory…. EGT at full load should only be slightly higher (if not the same)

The tweaks you have done, simply put more fuel in at lower speeds/loads which in turn will make the turbo spin up faster (thus start boosting quicker) reducing lag and improving low speed pick up.


IMHO you should not have a problem, just remember not keep your foot flat to the floor for too long if you are worried.



Ian

[Topple]

Thanks Ian,

I'll let you know how my trip to salisbury goes on friday.

[Xtremeteam]

when i tweaked mine on sat i turned the diaphram from 11.55 to 3.15 & i rekon its runnin about 17 psi of boost (1n a wee bit bar) n it now goes like stink,runs out of gears even on 750's,

i was also concerened about the EGT thing as mines smokes most of the time when the coals being shoveled