NWDave

Ok, gauges are in and functional. Fuel pressure gauge says my lift pump is ok. Idle is 15, wot is 10 (at 70 mph). Just a quick short run on the freeway. My habits with the turbo cooldown were longer than necessary according to the EGT but then that was alot of city driving. <br>Now, the boost gauge. I've seen references to it as an item needed, not high on the list but a good item to have. On that basis, I installed one. Now, just what am I looking at? When I was doing 70, the gauge seemed to be reading about 19. At idle, it was 0. (I actually thought as I was pulling out of the driveway, &quot;darn, it doesn't work&quot; , fortunately, as I gathered speed, I saw needle deflection, whew.) Maybe I just need a simple, 1-2-3 lesson on what boost means to me, in relationship to hp production and what kind of readings might indicate potential problems. Anyone care to step up to the plate on this fine Sunday afternoon. <br>All in all, I'm very pleased with the Rod Pod and the gauges. I can't wait for it to get dark so I can see these ISSPRO EV gauges. <br><br>Top, you're gonna wish you had the Rod Pod. Looks much better than a Pillar. Thanks to Scotty and Rod for another fine product. You guys outdid yourselves. <br><br>~Dave

RATTLINRAM

Dave,,,,,, Just my $.02 on the boost gauge, <br> I kind of look at it this way, my boost readings vary with how much work the motor is doing. I know that I should see right around 19-20 at WOT. I know that if the truck ain't acting right and my boost numbers are low,,, I need to check the intercooler hoses and intake connections.<br> At a steady speed, on level road, I still see flucuations when running into a head wind or when the cruise control backs off just a little when the tractor-trailer that just passed me pulls back in front of me and the motor doesn't work so hard because of the draft from it.<br> All in all, I think of it as more of a diagnostic tool,,,,,, plus,, it's neat to look at! ;D ;D<br> Maybe someone will chime in and give us both a better explanation.

chuck3

Dave at idle you should see 0, floor it from a stop and it should jump up to 19 to 20 or so. running 70 mph you should see 5 to 7 give or take a couple depending on head winds, inclines etc.

P Kennedy

Cummins put out a motor minder boost guage a few years ago that showed both boost+ and vacuum- with a zero at top. This was supposed to be the answer to fuel milage, ECM's and trip computors superceded this item. At idle your truck basically is naturally aspirated and draws vacuum, this condition changes as power is needed to move combined with rpm. Turbo is turning but no + pressure is created until exhaust side of turbo is pushed hard enough to generate pressure on the intake side (turbo pushing more air than engine would use just by running) creating PSI to increase until defueling or wastegate dumps. PSI's will vary depending on year,settings,bombings and air density. When wastegates started being used variances in top PSI readings due to air density became more consistant ie;19-21 psi stock. Without the WG pressures would fluctuate seasonally 5-8 psi (19-21 summer to 26-30 winter on my 91). Like any guage there is a normal range in which your truck will operate, sudden drops while driving under normal conditions could mean leakage in charge air system, plugged air filter, plugged fuel filter and with a few other things including EGT (higher) and black smoke. So clear as mud in a 5 minute lesson right. PK

RATTLINRAM

Yeah,,,,,,, What PK said. ;D<br> I guess I should have also stated my readings @ idle are 0 and anywhere from 3 to 8 or so when running 65-70mph.

Stamey

My 99, with the cruise set, at 65 mph, on level ground only boosts 10 lbs, or a little less. 20 lbs at 70 mph seems too high, unless you are bombed.<br>Am I off base here guys?<br><br>Chris<br><br>

NWDave

Ok, the picture is starting to clear up. Well, tomorrow its back to work so I'll be back on the freeway alot (for me, anyway) so I'll get to see the boost under several different conditions. <br>Stamey: Come to think of it, that 19 was when I was accelerating to 70 (in a 60 zone of course). I may have been misreading it too. More mileage will give me better information for what is &quot;normal&quot; for my driving. Well, now I have a better understanding. Thanks for the info. Additional comments are always welcome.<br><br>~Dave<br><br>P.S. The night has finally arrived. Just had to go to the grocery store for some bananas . The gauge lights are sweet. ;D ;D<br>

Shovelhead

The nice part about analog guages is that the longer you have them the less time it will take to glance at them and see if everything's &quot;normal&quot;.<br>You'll get used to where the needles should be pointing for your truck and conditions, so a ''abnormal&quot; condition will be noticed with a quick glance. ;D

P Kennedy

Okay sorry I was in a hurry and left some details out, peak manifold pressure will develop pulling hard, almost max rpm and pedal on the floor. Driving down the highway guage will vary between 0-20? depending on throttle position and power needs, to better understand this if you hold throttle in one position while climbing a grade manifold PSI will increase as truck slows down. Press down throttle on grade then and pressure will be even greater along with the pyrometer readings as power levels increase. Fuel+air=heat=power. Before the days of ECM's and wastegates mechanical pumps were jacked up by various methods but the driver was the key in reading the three most important guages (water temp,pyrometer and manifold psi) and using his foot while constantly pulling to prevent engine melt down. PK