Common Rail with NADS boost pressures

Gday Everyone
I am just wondering what kind of boost pressures folks are running in their CRD patrols after a NADS/Dawes and Needle valve installation. I have mine set at 19 psi peak and about 11 to 12 psi for cruise. Cruise pressure is a bit hard to read as the slightest touch on the throttle will make it waver a fair bit. (distinct lack of flat road around here). I towed our boat for the first time yesterday and found that it dropped off boost a bit too easily for my liking and was thinking of upping the boost levels a tad more. TIA.

I think you will find your boost levels are at the top end for the CRD's. If anything I would ever so slightly screw in the needle valve just to raise your cruise boost another psi or two. But thats how I would like it... Towing will kill the boost levels at the same rev range when not towing. It does this when I tow my camper. I just drive differently to suit.

I set the boost controller so we took the spare tire pumped MPa, connected with boost, and then rehearsed 1.4-1.5 MPa. Pressure turbine shows 0.9 MPa at maximum .

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Originally Posted by Snow Patrol

Gday Everyone
I am just wondering what kind of boost pressures folks are running in their CRD patrols after a NADS/Dawes and Needle valve installation. I have mine set at 19 psi peak and about 11 to 12 psi for cruise. Cruise pressure is a bit hard to read as the slightest touch on the throttle will make it waver a fair bit.

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Hi mate. Mine is set to max 19 as well, although I have to really really push it to hit that number, normally it's 16-17. This gives me enough juice for my liking. Now I'm not going to answer whether it is safe or not, upping the boost a tad, but from factory boost spikes can be much higher than that (without dawes and needle).
Funny you say your boost is erratic, it should have a very smooth curve after needle and dawes.

Might have a leak or the gauge is faulty, check all fittings and joins

Cruise pressure is a bit hard to get right if you don't have a long flat road to test it on. As your foot on the pedal will move over the slightest bump and you will see your boost move in accordance to this. Just get it as best as you can really. 19PSI is fine for these motors and turbo. The turbo will easily go to 30 psi, but at that pressure it will be just pumping hot air and you will more than likely snap the impeller shaft on the turbo if kept at that rate. The overboost warning I get comes on at 30psi in my DI but no limp mode. Just a warning from the ECU, so I can't really say for the CRD's what the overboost warning is on yours....Maybe the same?

Thanks Guys
I was just wondering/ making sure I was in the ball park I guess and making sure I wasn't going to do any long term damage. I took the troll for a drive again with the boat on when it was cooler and wet and saw 20 psi but had to push it pretty hard. Mudski is right about the slightest bump moving the needle on the gauge as I paid extra attention and found this to be the case. I have upped the cruise to 13/14 and it seems to hold a gear a bit better also. EGTs are at about 500 on a hot day towing a 1.2t trailer and easily controlled. The troll is much smoother with the Dawes and Needle valve installed no question. Down the track I will go for a new exhaust which should give me more torques and maybe a chip if the Minister for War and Finance approves the expenditure.

I'll tell you, get a pipe before a chip. I removed the muffler from my 3inch pipe, so its just the high flow cat, and the difference was outstanding. Heaps better for towing.

Ended up dropping boost back to just on 18 PSI. Went for a drive up to the Outlaws on the weekend and got a limp mode at a bit over 20 psi on the freeway which caught me by surprise. I did have my pressure set too high and I found I would subconsciously back off the right boot a bit around the 20 mark and I had not tested it at freeway speeds. I did wind up my cruise pressure just a tad as Mudski suggested. Troll does tow much better and seems to use less fuel.

IMO a pipe alone will see a little gain but combined with a chip you'll really feel the difference.
Another mod I highly recommend you look into is a Autron Cruise Control,
mine holds speed up hill towing so very happy