13 mmP-pump
TheBoschP-pump,theheartandsouloftheengine,canbe
spottedin theliftervalley.CourtesyofHypermax,it’sbeen
fittedwith 13 mmplungersandbarrels,a quick-ratecam,
andanAggovernor.AccordingtoFerenc,thepumpis set
extremelyconservativeforProStock,yetatthesametime
supportsmorethan1,800hp.AccommodatingtheP-pumpis
a billet-aluminumfrontcover,intermediateplate,andadapter
plate,alongwiththecorrespondingpumphubandgear.A
belt-driventransferpumpsuppliesadequatefuelpressureto
theP-pumpwhileeightoversizeinjectionlinescarrydieselto
theinjectors.60 PSIofBoostandIce-coldIntakeTemps
In ordertomeetProStockrules,the7.3Lis forcedtobreathe
througha single,3.6-inchsmoothboreturbocharger(i.e.
nomapgroovetotakeadvantageof).Andwhilethisairflow
limitationdefinitelyseemstoholdthebigdisplacementV-8
backa bitmorethanit doestheCumminscompetition,the
JumpingJackFlashguyshavemadethemostofit. Withdata
logsthatshow 60 psiofboost,EGTthatrarelyexceeds1,700
degrees,andintaketempsthatstaybelow 80 degreesthanks
toanefficientwater-to-airintercooler,durabilityisn’tbeing
sacrificedin ordertoruna littleclosertothefront.During
SuperStockorexhibitionhooks,the3.6-inchchargergets
ditchedin favorofa 4.1-inchunit,andthe7.3Lresponds
verywell.“Whenwethrowthe4.1onthere,thisenginereally
likesit,”Ferenctellsus.Fromthecaptain’schair,Nathanhasplentytolookatwithtachometer,
boost,oilpressure,watertemp,andfuelpressureanaloggaugesinfront
ofhim.However,a Racepakdataloggersystemis themostvitaltoolin
thisworkspace.Followingeveryhook,therecordeddatais reviewedand
thoroughlyanalyzedtomakesurekeyparametersarestayingincheck,
tohelpimprovethetruck’snextperformance,andsometimesevento
findoutwhatwentwrong.Transferringpowertothegroundbeginswitha four-discCrower
clutchconfinedwithina one-offbellhousingbuiltbyCustomFloaters.
Insteadofrunninga Reversertransmissionintheconventional
locationdirectlybehindthebellhousing,Ferencandcrewoptedfor
ProFabMachine’sUltimateQuickChangetransfercasewithReverser
setup,whichcombinesthetwocomponentsintoa single,weight-
savingpackage.Beneaththecold-sidewater-to-airintercoolerpipingliesthemagicbehindthemechanical7.3L:theP-pump.
HypermaxtreatedtheBoschinlinepumpto 13 mmplungersandbarrels,a hot-rodcam,andanAggovernor
thatprovidesfullfuelingallthewayupto5,800rpm.TheP-pumpsendsfuelthroughspecially-bentinjection
linestoeightinjectorssimilarinappearancetowhatyou’dfindina DT466International.Hypermax’sinjector
adaptersleevessimplifiedtheprocessofconvertingtheinjectorstylefromHEUItomechanicalwithoutrequiring
extensiveadditionalmachiningoftheheads.A water-to-airsystembasedarounda SandridgeCustomintercooleranda belt-drivenwaterpump(bothof
whichwereobtainedfromHaisleyMachine)keepsintaketempsenteringtheengineintheupper70s.Withthe
aforementioned4.1-inchchargerinthemix,intaketempsjumpuptoroughly 100 degrees(alongwithboost
checkingin10-psihigherat 70 psi).Additionalcoolingcomesintheformofa nine-nozzlewater-injection
system,designedandconfiguredtokeepEGTfromcresting1,700degrees.JUMPING JACK FLASH
56 OCTOBER I 2019 • DIESEL WORLD http://www.dieselworldmag.com