neo
08-05-2010, 08:23
So I have a bunch of quesitons, but going to start here. Recently purchased this 96 Burb K2500 and love it. I installed a boost gauge and see the boost never stays very constant. I have read many of the posts during my research that make good arguements on both sides of the "mechanical" v.s. "electrical/computer" boost control and don't really understand why, if it is, bad to run boost all the time. Yesterday, I had to drive about 2 hrs away and figured I would play with things a little. Since I have a boost gauge, pyro (post-turbo) and temp guage, I figured I would try a couple combinaitons. Never, did I exceed 8 psig of boost, using the trottle to insure that. But running at 70 down the highway, with the computer doing the controlling, I would only see boost climb to a max of 6 or so psig, the EGT was reading about 450 dF and the engine temp (stock gauge) shows about 200 dF (just under the 210 on the guage.) If I switch the lines on the control solenoid that lets the vacuum go to the wastegate controller, it seems to simply hold the wastegate shut - yes, cheap way to do this, but I was on the side of the road, then it runs pretty much the same in terms of power, however I do have to watch the guage to let off as the boost climbs. The temps though are a little different. At 70 mph under similar condition (road slope, wind, ambient temps) the EGT ran about 50dF cooler, the boost ran pretty constant at around 5 psig, but it apeared as though the coolant temp climbed ever so slightly up abotu 5dF - keep in mind the guage pretty much sucks.
So, is it really bad to run constant boost like this? I honestly don't know. I can kind of see why temps might climb a little in the cumbustion chamber, but don't understand why my EGT drops unless it is becuase it is fuller combustion in the chamber and less "combusting" on the way out?
The TurboMaster is one option cause the elimination of the vacuum system, but the computer controls seem to be alright also. The arguments I have read make sense on both sides and I am trying to figure out what is the best option for me. I rarely tow, live near the coast where it is flat, but do use the truck out on the shoreline in the thick sugar sand where it has to work very hard.
I tired to make the "boost fooler" circuit, but it just through DTC's so I must ahve messed something up. I'll probably take another look at that this week. Any guidance/input is apreciated.
So, is it really bad to run constant boost like this? I honestly don't know. I can kind of see why temps might climb a little in the cumbustion chamber, but don't understand why my EGT drops unless it is becuase it is fuller combustion in the chamber and less "combusting" on the way out?
The TurboMaster is one option cause the elimination of the vacuum system, but the computer controls seem to be alright also. The arguments I have read make sense on both sides and I am trying to figure out what is the best option for me. I rarely tow, live near the coast where it is flat, but do use the truck out on the shoreline in the thick sugar sand where it has to work very hard.
I tired to make the "boost fooler" circuit, but it just through DTC's so I must ahve messed something up. I'll probably take another look at that this week. Any guidance/input is apreciated.