1.9TD turbo boost

JohnCKL · Post by **JohnCKL** » 07 Sep 2006, 06:29

Thanks. How much does it cost?

JohnCKL · Post by **JohnCKL** » 07 Sep 2006, 06:30

double entry

KP · Post by KP » 07 Sep 2006, 17:03

I dont know you would need to email him to check. IIRC about £24 or such like

JohnCKL · Post by **JohnCKL** » 08 Sep 2006, 08:24

Just went for a test run yesterday. Seems that the last full turn finally boosted my turbo from 0.85 to 1.00 bar. Maybe because I sprayed some silicone lubricant under the nut, not sure whether that did the trick. The test run do need a long uphill stretch in 4th gear.

JohnCKL · Post by **JohnCKL** » 15 Sep 2006, 22:43

8304,

Boost compensator valve:

you have wound the torx screw down, this provides the engine with more fuel throughout the range but the biggest increases are gained when your remove the alloy top of the compensator valve. Remove the diapragm and spring beneath and wind the spring base down (clockwise) three turns. Then put the diapragm back in with the accentric taper on the bottom of the pin to the right (allowing the "reader pin" inside of the pump on the left to perotrude further.)

Before removing the alloy top to tweak the compensator valve below, do I need to wind the torx screw back up to original position? I think I will do it soon but need confirmation.

8304 · Post by **8304** » 18 Sep 2006, 13:52

there is no need to wind the torx back to the original position. All the torx does is set the starting height of the diaghragm. The only thing is if the torx is too fay down you will be using more fuel when off boost than you need to. and if the torx is wound too far up you will be reducing the fuel when off boost.
Winding the spring base down increases the maximum possible fuel available when on boost - it will not effect the off boost running or fuel consumption.

hope it makes sense!!!!

JohnCKL · Post by **JohnCKL** » 18 Sep 2006, 17:45

Thanks. Will try it out later.

KP · Post by KP » 18 Sep 2006, 18:05

Is there an online guide to this kind of thing at all?
Pictures would be usefull, or even a How to Guide if possible.

Its a bit hit and miss i guess getting this right if your doing it for the first time but a few of you on here seem to be very knowledgable about this kind of thing and i would think it would be easier to create a How2 guide and post it up and then it could be refrenced and improved as times go on and to help people out

mpr1956 · Post by **mpr1956** » 19 Sep 2006, 00:26

Hi all, although personally I regret playing with the settings of my turbo and pump ( I must have left black clouds all over Wiltshire!!), I can see there is a lot of interest, so here are a couple of sites I used to improve performance of my 93 tdsx...

http://dodgeram.org/tech/dsl/more_power/Power_ve.htm

Another is ..

http://www.club-306.com/forum/index.php?page=2

There are a few others, so you have plenty to go on for now

Remember to note the original settings before you start, so you can go back to them (for the UK mot smoke test if nothing else !)

Best Wishes, Martin

8304 · Post by **8304** » 19 Sep 2006, 11:13

ive actually started to type a guide to tweaking the various bits we have mentioned on the forum recently. Its motivated me to finish it so i will do that ove the next couple of weeks.....

with regard to smoke tests at MOT, you will find that there isnt any problems because the biggest increase in fuel and so emissions comes from the compensator valve which only has any effect when you are on boost - reving the engine for the smoke test doesnt cause the engine to run boost as it isnt under any load.

however, if the maximum fuel screw has been adjusted (the one that deals with off boost fueling) too much then you might get problems but mine is turned right up and hasnt given me any problems at mot..........

there is no hard and fast rule for playing with the pumps on these engines. You have to ballance fuel economy with extra performance and smoke. I expect to see a puff of smoke when i first put my foot down as the extra fuel arrives instantly whereas the extra boost from the turbo takes slightly longer to arrive as the turbo has to spool up, and so for an instant there is not enough air for all of the diesel to burn and so you get smoke (unburnt or part burnt diesel)

The turbo's however can be measured - with a boost gauge. I find that above 18psi the gains drop off sharply as compressing the air causes its temperature to rise and density to decrease, meaning at say 22psi you will have less air per unit volume than at 18psi. - better intercooling would combat this and give good gains inpower above 18psi but i havnt gone down that route - yet....

JohnCKL · Post by **JohnCKL** » 19 Sep 2006, 11:28

Will increasing the turbo boost provide more air/power throughout its range or just provide higher peak boost?

8304 · Post by **8304** » 19 Sep 2006, 12:17

by turning the boost up you raise the maximum power which the engine can produce at the top end (providing fuel is increased to match)

by turning up the fuel on the max fuel screw (on right of bosch pump looking at front of car) you effectivly increase the quantity of exhaust gasses produced at any engine speed so the turbo will begin to spool up at lower rpm.

from memory mine used to start to spool up at around 2500 rpm - now its about 2100rpm which means the engine has a wider rev range where it is useable.

Think of it like this: the very reason why the turbo spins is because exhaust gasses are passing over its turbine. if you increase the volume of exhaust gasses for any set revolution rate of the engine you will be making the turbo capable of doing more work. you can increase the exhaust gas volume in two ways - reving the engine more or turning the fuel up so the volume at any set number of revs goes up. with the outcome of the turbo spooling up at lower rpm

hope its clear!!

KP · Post by KP » 19 Sep 2006, 19:10

The only way to really decrease the temps in higher boost levels is to fit a better turbo as the intercooler does a good job the turbo will be glowing red hot at these pressures for such a weedy turbo as well.
My GT28RS on the coupe still glows red hot after runs and the intake temps are a good bit lower with it when it flows more air than the standard TB28 turbo due to the compressor heating up and falling out of its efficiency island.
Its not all about pressure its about air mass as well. Denser air from a turbo that doesnt get as hot at the boost levels will mean a much better bang

JohnCKL · Post by **JohnCKL** » 20 Sep 2006, 07:27

8304,

How much did you tweak the max fuel screw? I turned it 40 degrees. Didn't go further yet.

Bigger turbo might not be suitable for diesels. I've modified mine to a bigger spool on the air side but noticed lack of power in low speed. I think the original size might just be engineered right for a diesel.