Boost Pressure

[jrjones26]

I have just had boost & EGT guages installed on my new truck. I previously had a Dodge which also had guages. What are typical boost pressures for the Dmax?

jrj

[Buck]

If the truck in your signature is the one? Around 2-5 psi on flat ground in overdrive and 23-24 psi under full throttle.

[jrjones26]

The 2 to 5 psi in OD is what I see mostly. However, it's never gone above 10 psi even when towing a 16k # trailer over a steep mountain. I have the Van Aaken Smart Box installed, anything that may be causing?

jrj

[sdaver]

something is definitely wrong.........pinched line or bad ground......7-8psi crusing flat ground 28-30 full throttle. What kind of guages?

[YZF1R]

You say you had them installed, as in someone else did it. Was it a new person? If you have the itsy-bitsy plastic tubing, it's VERY easy to over tighten the brass compression fitting and pinch a tiny hole in it. Just a thought.

Steve

[jrjones26]

The guages are the Westach combo guage from Geno's Garage for boost pressure & EGT. I had them installed at Texas Diesel Injection in San Antonio along with a BD exhaust brake. I used the same combo guage on my '99 Dodge & had no problem with them for nearly 5 years. I haven't checked the connections, or checked for a crimped line. I'll do that as soon as the weather improves.

jrj

[afp]

JRJ,

With 90HP Juice, I get 2-5 PSI at freeway speeds and 24-25 at full-throttle.

BTW, I live in Converse. I can show you how I installed mine. My e-mail: painterb@sbcglobal.net

Blaine

[YZF1R]

jrj, I'm not familiar with that gauge set up. Is it an electronic one? If so, it could also be a bad transducer. Just have it swapped out for a new one. Of course, I'm sure the people that installed it for you will make it right.

Steve

[Heartbeat Hauler]

A little clarification required here. I was under the impression that 19 PSI was max boost for a stock Duramax(under load). Is this correct? I say this because the stock wastegate is not adjustable and without some type of mod, not capable of anything over ABOUT 19 psi. :confused:
JP

[JMJORDAN]

Something doesn't sound right. My stock truck could easily hit 25 psi hauling that kind of load. Now with the Predator 85hp tune I can get 30psi running around empty. I would see if I could hook up another gauge and compare the two.

[ksevern]

Been a while since my last post/reply...

I know when the D-Max's first come out, some of the post-turbo intake tubing clamps were not properly tightened causing pressure leaks.

My understanding of the 2001's is the max pressure was set at 23 psi. This was too light and caused 2 over-boost codes on me and shut down the plant to limp-home mode. This was corrected with a software update. I also understand the chip kits on the market also move the over-boost up, or over-ride the factory settings.

[jrjones26]

I'll take my truck back to Texas Diesel Injection tomorrow and have them check their installation & the gauges. If all of that checks out, I guess I'll heve to remove the smart box & take it back to the dealer for further check out. Driving today, I couldn't get more than 8-10 psi boost under full throttle.

JRJ

[CPMac632]

Does it seem to be running as well as it did stock,or better, or worse?

[jrjones26]

Thanks for all the responses. I took it back to the guy that installed the gauges at TDI in San Antonio. He hooked the tube for the gauge up to a pressure supply & immediately found a severe leak in the line. There was a split about 1 inch long at the place where the tubing connected to the fitting. He cut off 2" of tubing then did another pressure test. 20psi on the regulator checked out at the gauge with 20psi. Now everything is hunky-dory. I get boost readings of about 22 psi under vigorous acceleration and readings of 4 to 10 psi driving into a moderate headwind at 65 to 70 mph. It seems more responsive now even though the mechanic didn't think it was enough of a leak to affect performance. I'm no mechanic, but I would think the loss of boost would affect performance.

jrj

[YZF1R]

Glad to hear everything got taken care of. Enjoy!

Steve