manicmechanic Posted July 21, 2009 Share Posted July 21, 2009 I've got an 03 granite tractor with a 427 and mack 10spd.I am always pulling heavy loads 120,000+.I think there might be something wrong with this engine,It has very little power and the engine is not very responsive.I've checked the turbo for cleanliness and bearing play,I also put 6 new injectors in and adjusted the valves.still no power.On a long hill the pyro gauge will sit almost at a 1000 degrees.I'd like to add a boost gauge in my dash.There is a spot for it in the gauge cluster.Can I just buy the factory gauge and plug it in or will the have to turn something on in the ecm???Also is there any way of safely adding more power to this engine..I'd like it to run like my 2004 460.I asked my local dealer about a power upgrade and they told me it would be so expensive they wouldnt even consider it...THANKS FOR ANY HELP.... Quote Link to comment https://www.bigmacktrucks.com/topic/10103-2003-427-boost-gauge-question/ Share on other sites More sharing options...
Lmackattack Posted July 21, 2009 Share Posted July 21, 2009 If I recall the 2001-2004 Mack engines were said to be pretty weak when compaired to others with the same HP. I have driven a few that felt lifeless even empty. As soon as the engine felt like it was coming alive you had to shift. Even tho it would pull 80k it never felt like it wanted too. I think there was a program to turn up to 480HP but the EPA killed that a few years ago. ?? Quote Link to comment https://www.bigmacktrucks.com/topic/10103-2003-427-boost-gauge-question/#findComment-38284 Share on other sites More sharing options...
bobo Posted July 21, 2009 Share Posted July 21, 2009 (edited) if you look on the intake manifold you will see two plugs on the top, thats where you will get your boost reading from. I would check out summit performance for the gauge, thats where I bought mine(check out my pics)no ecm adj. need if you use mech. gauge which is the "real" reading anyway! check out north west, or rochester fuel for upgrades I been running big turbo and inj for over a year runs a little hot up hill with foot in it(but its a Rb so to be expected) good luck Edited July 21, 2009 by bobo Quote Link to comment https://www.bigmacktrucks.com/topic/10103-2003-427-boost-gauge-question/#findComment-38285 Share on other sites More sharing options...
manicmechanic Posted July 21, 2009 Author Share Posted July 21, 2009 I have been thinking about larger injectors ,it just sux because mine only have about 5 thousand miles on them.They cost me almost 12 hundred from MACK and I'd hate to turn them in for cores.When you say egts run hotter up a hill, what can I expect for temps?R U using stage 1,2 or 3 injectors? How about raising the fuel pressure at the transfer pump, can that be done?? THanx in advance!!!!!!!!! Quote Link to comment https://www.bigmacktrucks.com/topic/10103-2003-427-boost-gauge-question/#findComment-38309 Share on other sites More sharing options...
bobo Posted July 22, 2009 Share Posted July 22, 2009 rochester charged me 86$ apiece for the stage two, I pull heavy (140 000) pyro temps get up to 1100 but drops just as quickly Quote Link to comment https://www.bigmacktrucks.com/topic/10103-2003-427-boost-gauge-question/#findComment-38321 Share on other sites More sharing options...
bts-4120 Posted July 22, 2009 Share Posted July 22, 2009 did the dealer say why it would cost an arm and a leg to uprate to a 460p don't waste your time and go to a straight 460 they are weaker than a 427 Quote Link to comment https://www.bigmacktrucks.com/topic/10103-2003-427-boost-gauge-question/#findComment-38324 Share on other sites More sharing options...
manicmechanic Posted July 23, 2009 Author Share Posted July 23, 2009 I brought the truck in to the dealer today to have them give a look.They found 2 troublecodes stored in the computer. high voltage in jake # 1 and fault in injector circuit #2. Still havent got the truck back,they feel the problem is a wiring issue...I ordered a service manual but it hasnt come in yet. I dont know where to begin looking .hoping a manual will have some sort of troublshooting charts in it Quote Link to comment https://www.bigmacktrucks.com/topic/10103-2003-427-boost-gauge-question/#findComment-38349 Share on other sites More sharing options...
manicmechanic Posted July 27, 2009 Author Share Posted July 27, 2009 got the boost gauge plumbed in today..Only getting 30-31psi tops..Very slow to produce boost.by the time it finnally starts pulling its time to shift.Anybody know how much boost a 2003 e7 427 should make??? Quote Link to comment https://www.bigmacktrucks.com/topic/10103-2003-427-boost-gauge-question/#findComment-38487 Share on other sites More sharing options...
mackdaddy1911a1 Posted July 28, 2009 Share Posted July 28, 2009 If I were you I'd call your local Mack dealer to find out the PSI of the boost. Good luck.Matt Quote THE GREATEST NAME IN TRUCKS MACK TRUCKS Link to comment https://www.bigmacktrucks.com/topic/10103-2003-427-boost-gauge-question/#findComment-38527 Share on other sites More sharing options...
bts-4120 Posted July 28, 2009 Share Posted July 28, 2009 your not too far off on boost 01 427 usually around 31-32 have seen 35 pulling long hills that is off the factory gauge Quote Link to comment https://www.bigmacktrucks.com/topic/10103-2003-427-boost-gauge-question/#findComment-38538 Share on other sites More sharing options...
cool mr grinch Posted July 29, 2009 Share Posted July 29, 2009 have you checked your fuel pressure? it is commonly over looked at shops, it should be running 59 at idle 80 at full throttle, the electronic motors like to spin the nylon gear away from the pump shaft. is it a vgt turbo? is there a large position sensor on the side of the turbo? Quote Link to comment https://www.bigmacktrucks.com/topic/10103-2003-427-boost-gauge-question/#findComment-38562 Share on other sites More sharing options...
Mackpro Posted July 29, 2009 Share Posted July 29, 2009 Factory spec for that year is 29-37 psi of boost at full load. Take the truck to a Mack Dealer and tell them you want the "throttle responce program" downloaded on the VECU ( and they will calibrate the throttle pedal) and any new software/datafile for the engine and vehicle ECM's. Its a free download from Mack, you should only pay labor, 2 hrs max. We do this to all AI engines and it make a big difference. It helps with the poor throttle responce between the gears. Most AI 427 and AI460 are the exact same engines but with different datafiles for different HP levels. The dealer can submitt a HP conversion request form to Mack, sometimes its just a free download to up it to 460HP, + labor to install program of course. However I did have a 2005 CT713 with a AI427 and requested a HP conversion to 460 HP and was denied, I called the engineer and he said on some AI's they couldn't bump up because of EPA reasons? Good Luck Quote Link to comment https://www.bigmacktrucks.com/topic/10103-2003-427-boost-gauge-question/#findComment-38575 Share on other sites More sharing options...
manicmechanic Posted July 30, 2009 Author Share Posted July 30, 2009 I am going back to the dealer tommorow.I will have them check fuel pressure and download throttle responce file..Thank you very much for all your responces and ill be sure to let u all know how i made out!!! I usually like to make all my own repairs , however , I've got a service manual on order for several weeks now and these electronic engines are a little tricky Quote Link to comment https://www.bigmacktrucks.com/topic/10103-2003-427-boost-gauge-question/#findComment-38577 Share on other sites More sharing options...
Lmackattack Posted July 30, 2009 Share Posted July 30, 2009 let us know how it goes.. Sounds like you may be on to something.. boost looks good to me. but I know more about the mechanical engines. have little info with the new stuff. does it blow any black? most of the new elec engines wont.. if it is throwing black and there is no power it could be a boost isssue or something with the timing or turbo etc... hopefully that pedal reprogram gives it some life. I was not impressed with the lack of power with my friends 02' 427 mack with a 13 speed. my little 285 maxidyne with a 6 speed would walk away from it thru 1-4 gears and holds its own all the way to the middle of 5th gear.. h Quote Link to comment https://www.bigmacktrucks.com/topic/10103-2003-427-boost-gauge-question/#findComment-38586 Share on other sites More sharing options...
manicmechanic Posted August 25, 2009 Author Share Posted August 25, 2009 Well I got the truck back from the dealer...They said It had a really outdated program file in the computer and they downloaded the latest greatest file for a 427,atleast the best the could do and still be emmisions compliant! The truck runs a lot stronger , still not as strong as my 460, but acceptable.My next step was to relace my muffler with a freeflowing unit from pittsburgh performance. What A Difference!!!! Lowered my EGT,s by almost 150 degrees AND picked up about 4 pounds of boost.It was a little bit of a pain in the as% to install ,being a 5 inch pipe where as mine was a 4 inch inlet 5 inch outlet. that wasn,t too hard but this muffler is also a 10 inch diameter where as mine was a 9 inch.A little fabrication to the muffler mounts and pipe and all is well...The muffler cost about 160 dollars plus about fifty bucks for clamps and such.Best couple of bucks I've spent on a truck in a long time!!!!!! Quote Link to comment https://www.bigmacktrucks.com/topic/10103-2003-427-boost-gauge-question/#findComment-39551 Share on other sites More sharing options...
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