redneck1

I just installed my pyro and boost guages and I am curious what boost reading you guys are getting. My old 2003 could see as high as 25 psi (stock) when I floored it. This truck only went as high as 20 psi when floored in 3rd and 4th gears. Boost at 60 mph was 4psi. Does this sound right as it seems low compared with my previous truck.

redneck1

Has any one bench marked their 4th gen prior to putting on a programmer? My Smarty is due in on Wednesday so I just wanted to see what every one else was running. All my numbers are without trailer and on flat surface.

roughstock

You will only get boost under load, crusing at 60 isnt much of a load, so boost will be low. however, cruising at 60 up hill with a trailer is a load and boos will be much higher. what was your previous truck?
but as far as 4th gen numbers, i cant help. i just finally moved up to 3rd gen. So in another 10 years, ill have a fourth gen. lol

SOhappy

I'd hit 33psi all the time on my '03 with the Edge boost elbow installed.

A hard 100,000 miles and never had any boost-related trouble with the truck.

Not sure what the '11 pushes- still stock.

redneck1

My previous truck was an 03 CTD. I had the guages on it and if I floored it (empty on level ground, NV5600) I would hit 25 psi. That was completaly stock with out any mods. Since I'll be deleting my 2011 this weekend I wanted to benchmark it. So far the most boost I've seen out of it is 20 psi (empty on level ground). Just curious if the 6.7 runs lower boost than the 5.9. If that is the case it might explain some of the CH gasket failures.

Busboy

If you are still stock try pulling out the manifold pressure/temp sensor and have a look at it. It was so bad on the manual truck even after cleaning that we replaced it. There was no way it could read correctly. The auto with 7500ml was still ok after cleaning. Ahhh never thought you may have installed an aftermarket new boost sensor or be running a mechanical gauge.

redneck1

Where is it located and I'll pull it when I get home. BTW, I installed the air line for the mechanical boost guage in the intake horn. Not sure if that makes a difference.

Busboy

It's located in the intake horn on the rear side, one screw holds it in, lube the seal before reinstalling. I suspect that it's the most accurate location for it except for the carbon build up from the ERG.

redneck1

OK, I pulled it out. There was quite a bit of soot on it. Given that the truck only has 18,000km on it the amount of soot was shocking. I cleaned it out with some isopropyl and reinstalled it. BTW, my boost is mounted exactly opposit the sensor. I did a few mile on the truck yesterday and here are some numbers (once again the truck is stock everything running empty):

1. at 65mph steady 4 psi - EGT=800
2. when accelerating in traffic (moderate to hard) anywhere between 12 and 20 psi - EGT between 700 and 1100
3. at steady 45 mph (5th gear) boost at 0 psi and egt = 600

One interesting thing I noticed was that on the highway at 65 mph a regen started. My boost pressure immediateley went from 4 psi to 0 and egt went from 800 to 1200 .

So these are baisically my baseline numbers. Now I'm off to the UPS store to pick up the Smarty Jr. I would like to thank Lary at the DTR store for setting me up with the delete system. Guess what I'm doing this weekend .

Busboy

It's hard to believe that soot coated/clogged sensor decides how much fuel to pour into the engine isn't it. I'd like to bet very few have ever removed it to clean it. Of course it's not a problem if you are deleted.