designing the nissan vh45 engine-information

8/3/2019 Designing the NisSAN VH45 Engine-Information

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Tbe .Ellgineering SocielYFor Advancing MobilityLand Sea Air and SpaceINTERNATIONAL 400 COMMONWEALTH DRIVE , WARRENDAlE, PA 1509&.0001 U.S.A.

SAE echnicalPaper Series900651

Development 0 " aNew-GenerationHiqh-Performanc ..4.5-liter v a NissanE.ngineM. KLnoshita s..Shiga, T..Hlrai.,a.nd K. SugiharaNissa MotorCo...Ltd.

T. FukuharaJapan Electronic Control Systems co, L d.

Reprin.ted from SP..823 -New Design and Adva.ncedComponent Design

International Congress and ExpositionDetroit, MichiganFe bruary 2 6 - M arch 2.1 .9 90


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900651Development ofa New-GenerationHJgh...Performance 4..5..1iterV8 NissanEng.lne

ABSTRACTThiS paper describes 8: new 4 _5 ~lite r V 8 eng in e,V H450E . 1.vhfch was developed for use in thelNFINrT i

Q45 sporty luxury sedan that was releasee in the U_S .and Japanese markets In Novem ber 198 9. The m any v aengines [n use around the world can be o oadry dev[dedinto - ','0 catecorles. O ne cate go PJ is cha ra cteriZ ed byample torque at low engine speed and relatively largeen gine d isp la oeme n . T he o tne r categ ory is characterizedby en ha nced p erfo rm an ce at re la ive ly high enginespeeds. The VH450E engine is a ne~rgenera ion VBpowerpfant tn a delilJ ers smoo th powe roulp ut at to~endspeed and also generales ample torque at low enginespeed. to main ta in gooo id le stablity ,and acoomplishesi ta ll w ith th e sma lle st p os sib le d Is pla cement

o ,evelo pm entefforts w ere focused o n tw o main goals.T he first w as to achieve efficient intake air charging. T hishas been acco lprished Ihe' .intake air resonan point at arelativ ely high e ng in e speed Ih ro ug h ap pro pria te inta keb ra nc h a nd co lle cto r tu nin g .. A d ditio na lly , h ig he r c ha rg in ge ciency at lo ' ,vengine speed has been achieved byusing N issan's aerodynam ic intake port and the N issanvalve tim ing control system . These features assure highchargingeffic iency from idle speed to the rev lim it. Thesecond goal was 0 reduce losses resul.ting frommechan ic al fric tio n. F or th is p urp os e, ro lle r ro ck er a rm sand m olyM enum -co ated p isto n skirts are used to reducehie ion. As a result, the engine p rovides superb high--speed power (6900 rpm rev lim it) and also low~speedtorque. Fur th .e rmore , t he a lum in um c yl'in de r b lo ck a nd thehigll-rigidity d esign o f the main structural parts combine toach ie ve go od en gine s oun d qu alit'J .

THE P RO JE CT to develop t n . e IN FIN IT I045 sportyluxury sedan was launched in 198 4. The aim oflhispro e'ct w as to build awono-ctass luxury ca r tna wouldr-e fle -e tJ apanese des ign sensitiv itY ,o ng inalit y and is sanethnology. Market research f indings had indicated that

M. Kinoshila, S. Shiga,T. Hirai', and K. Sugiha.raN iss an :A oto r ce. , LtdT. Fukuhara

Japan E lec tr on ic Contra! S ystem s co., Ud

the luxmycarsegment in tile U.s. and in other marketswas expected to gfO'oh!In the com Ing years. Am ong thethree drvisons making up the hJXWY ca r s~ment, theINFIN IT I 045 '.vas targeted at the functional luxury carc ate go ry (Fig . 1) . The a tt rihu tesof a car emphasized' bycustomers in Ihissegmen Included wei -rnaoeworkmansh ip . du rab il it y. safety and goo d trade-in value.Markel research r-esu s showed that the lu xu ry cars thesecus tomers I ;'.' er eaclua lly dr! ing tended. to have the10[[ol,'ling characteristics. They were higher p rice d th another cars in the [uxury car sagmen; they providedexcellet handling and st:abU ity and superb powerperfom1ance; eir interiors had few dscora iv eembe llis hme nts ; lh ey we re popular am ong relativelyyoung, aLuent buyers (T able 1). B ased o n these findings,the m ajor developm enobjed :ives set for the INFiN IT I045 ~,:ereto achieve e best d ynam ic perform ance in itscla ss, p rem ium qua lity, h ig h re liaJ Jirty a nd d ura)Ility, an dquietness and co mfort befit ng a luxury car.

The power un at the heart of the 1 F1NITl 045 vmuldbe the VH45DE engne, w llich was ne y designed a dengmeered v ir tua ll y f rom the ground LIp.

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fam llr ---- -- '- ------- Sp01tIEtooomlt lli ll C I W P r lc , !!

Rg, 1 LUXURY CAR SEGMENT

STYLIG SEm ENTS'YOU .GER RICH' HANDU G &

TRJIJ)mor~ALLUXURY

CONSERVATIVESTYLI G'4 DOOR BODSTYLI G, O LD ER

HIGH STYLELUXURY

'ADVANCEDSTYUNG 2 DOOR BODY

G.ENERA.ON GENERAnON'VERY SOFTYRIDING COMFORT'VERY LARGEINTERJOR SPACE

FUNCnONALLUXURY

HIG ER PRICETHAN OTHERLUXURY

ACCELERJ..TINGPERFORMA.NCE

FEWERDECORATION YOU GE:R&MJDDLERICGENERATION

\IVB.l . . MADEDURABIL ITYSAFETYT R .A .D E IN VA lU E

Table 1. FUN.CTlONAL LUXURY CAR SEGMENT

ENGINE ,DESIGN CONCEPTsince Ihe VH45DE engine was int.ended to be thepO\Yer source of the .t FINITI Q45,the basicdevelopment was to pursue the crsa ion of a n en ginesuitable for use ina V i orld-dass tuxurycar. The foremosobjective V i a s to achieve am p I.e lo w-e nd to rq ue to ge th er

\I..ith high power output in the high speed range, acba rac e ris tic without parallel in this car class. T he result\,. 'ould bea true new-generation VB enginecharacteristics never before seen inexfsting vapowerp lan s, enab.rng e INFINTIl 045 0 delr'v 'er thebest performance ,in its cla ss . T oa tta 'in th at o bje ctiV e., agenerous d-splacement size of 4.5 litter was chosen,a~ong w ith natural asp iration and a design w fthfourvalves per cylinder. careful. atten ton was paid 0 theengine oonsbuctionsoas 0 assure good noise an dvibra.ioncharaderistics, absolute retiability and excellentQuality (R g. 2). Specif ica ll y, t he major d ev elo pm ent g oa Jsincluded;

- the bes dynam ic performance in its class in als pe ed ra ng es , w ith ample powe r deliv ered smoo lh lyin d irect response to he driver's wishes;- Q uiet operation befitting a luxulY car al.ong withcornfortable sound cnarac e ris tics th at are linearelative to the engine speed and have noperc.eptible peaks; .- h igh rerab -[ it yand, ma ln tenance -f ree operat ion ;The advancedenglneechnologies Nissan hasperfected throug many years of auomotiveengineertng,experience were utilrzed to build a high-qualitypowerplanlhat wou d achieve U le se g oa ls . The majortechnical features of the VH450E engine include theNissan valve timing control system (NVCS)aerodynamic ports, dual exhaust system

scdlnrncooledexneust valves Nissan direct ignitionsystem (NDIS) timing chain drive, crOSS-flOW watercoolinq system, roller ro ck .e r arm s, m olybd en uffi-coated piston skirts and an integrated engine andautomatic transmission control system., FUNCOONAl

L U J l I i J R V I Y~I

R g, 2 ENG1NE DESIGN CO NCEPT

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OUTLINE OF THE VH45D,EENGINEThe VH45DE is a 4.5{jter 32~val\le DOHC 90" v awater-cooted engine. II generates m axim um poo ero t278 Hp at 6000 rp m an d m axim um to rque of 292 U)ftat4000 rpm . Front .s ide and op viell.!s of engine a re sho \!min Fig,. 3 and lts main speci f ication are g iv en in Tabfe 2.

:\lVa ercooli ggasolie4cycle ' ,: B . 90~ Varrangemen

Typeumbe r o f cylinder,arrangement~lg~io 'nbusion

Valve mechanismella;"

: D OH C. 4 valve,: 4,494 (c.e.):93 X 82.7 (n ): 112 (0101): 22 (mm): 2 20 .35 (nvn): 10.2: 1 6 , 4 ,. ( r n m . ): 52 (null):147 (mm): Jnt3!J.(n.\n~)".Ex~33 (ml'n):Mul fXl[nhnJeclio ,EGGS ':"T'VV'C+ '.control + EG'R: 278HpI6OO0rpm(SAE ne): 292lb .- ~ OOO rp mSAE net): - 8 -7 ~3 -6 ,. .5 -4 ~2: 890(l)X740(WIX725(H), (nvn)

T able. 2 M AJO R SPECIF.ICATtO' S

Front

BASIC ST,RUCTUREA cross section of the VH45DE engine is shown inR g. 4. T he bas ic structure and eatures 0 I he eng ine a reexp la in ed below .An aluminum cynnder block, w ith a closed. u pp er d ec kand deep skirt, was adopted-to re du ce tl1 ee ng in e w eg ht.The compact com xrs tion chamber has a cross-flowpentroo f oonfi gura lon Wi th a cen traJIy rotated spark pl.ugEach c y1 in de ris p ro v id ed with tw o intake and t'oVoexhaustvalves, placed at Tnduded .angle o f 4 6". T heinlake p ortsfe atu re N is sa n's a ero dy namic port ( 1). Sod iu rn~ coo le dvalves are employed on the exhaust s ide to lower the'rtemperature when exposed to hfgh'emp.eratureexhaustga s (Fig. 5).

U~ l hoeFig. 5 COMBUSTION CHAMBER OF THE Vl- f45DEENG INE

Plan

Side

Fig. J OUTLINE DRAWINGS OF THE VH450E ENG INE

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Fig:. 4 CUTAW AY VIEW OF THE VH45DE ENGINEThe intake man[fold is built w ith branches of equallength to each c ylin de r and are fed by a o ommon surgetank positioned betw een the .ro banks. T he 'branches

from the surgeank to each port have a g ra du allyta pe rin g d ia n e re r at midl""length that lorks 0 improve aicharging eff i.ciency in the l o w and medium speed ranqesThe exhaust manifo ld o f each ban k is made of stainlesssteel piping fo r lighte r we ight and the dual system designis e ffective in reducing exhaust losses.The engine o oo fng s ystem feature sa. cross-flowdesign (4 ), w .ith co oling w ater ro uted from the pumpthrough galleries between the banks and distributeduniformly -into ea ch ba nk to p ro vid e even coo ling o f theeight cylinders. Coo lin g wate r n o W ' s over tne cylinderheads from the exhaust side 0 collect on the in take sid eand from mere i t r etu rns to the rad ia to r. The thermostatislo cated befo re the ~ '/atef p um p an d co ntro ls the wa.er

tempera tu re a t th e eng in e ln ls t to a c on sta nt level.

The valve train ISo the swing arm type, havIng asmaJ ler inert ia l weight hat helps to achieve higher enginespeed. Hydraulic la sh ad jus te rs thateJiminatethe needfo r v aJ ve cle ara nce a dju stm en ts are positioned on theinside of he cam shaft and ro lte rs have been incorporatedin the rocker arms. The NVCS system (2) is frUed to theends of the two [nake camsha fts to control he valvetim in g . ... .Ig ni 'o n is accompnshedby (he NDIS system (3) whichelim inates the need fIX a d is tributor and high~ensioncables. The power transistors provided fo r each cyl tnderbank send an lqnftion s ig na d ire ctly to tile coils mountedabove each s pa rk p lu g .. T his ig nr io n s ys tem thus assures

8. stab e supply of secondary voltage at high enginespeed.Thefourcarnsha.s are driven off (he crankshaft by

single~s1rand rolterchans, \!o'itheach .ban having it s ownchain. T Ilechain~ drjv en. o il pum p opera es off a shaffsepara te f rom til e c ranksha ft (Fig . 6).

Fig. 6 CHAIN . LAYOUT OF THE VH45DE EN.GINE

OUTPUT 'PERFORMANC,Ei1 h theexoeption of some sports car pow:erplantsmost V 8 engines have been design,ed w ith a largedisplace m en to g.enerateabundant lov-end torque.Howeer, to achiev e the perf ormance in tended for theINFINIT1 045, emphasis ~as placed on providinghighspeed power output as well as amp e low~eJ1torque. Tha mean the VH45DE engine would need 0deliver p leas ing sporty aeeeteranon performcanceup 0the high rpm range and sm oothness befitting a luxury car\, .~thno d 'scomfOf ting G sensa tio n durin g s tand ing-s ta rtacceleranon or lransm 'ssion shift shock. Thetechnolnqies tha t were employed to achi.eve theseperformance characteristics are explained in thefolfoY,ingl discussion.

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MUl T lV ALV E D ES IGN -AI.ong w ith the s ho rt s tro ked es ig n(s tro ke lb ore= 0 .99 ), e ach cylin de r is p ro vid ed w ithfour val es f or bet te r air intake efficiency. T he tw o in aksvalves have a d iameter o f 38 mm w~hile that o f the twoexhaust valles is 33 m m. The ratio of the valve diam eter0: the bore is a large 0.41. To improve oombus ione ffic Ie nc y., th e c ombu sU on ch ambe r w as g iv en a compacp en tro of s ha pe with thespaf1< p lug loealed in its cen er.The compression ratio was seta 10.2 and the engine isintended to operate on prem ium gasoline (Rg. 7) ..S KO R tsT R OK ES IB "" v!9L J ,R & E l N TM E '; ' ' ' l V E C I A V , M .Y I !:C I II IB O R E " "l U IP l I f T R O O f C O W B u S 1 1 0 N e~AIlSSlCE N fE l ! Pl U G P O S l n ( I i I r I Il i tO .H O O N 'P R E SS IO t f 1 M T IO 1 1 1 2

Fig. 7 M'UlT1NAlVE DESIGNVALVE TIMIN.G-It is well known tha the valve ttmingl.vhich provides m axim um air cha rg ing efficiency vanesacco rd iog to th e e ng in e o pe ra tin g c on ditio ns . S in ce 1986,issan has been using t e NVCS sys em v . 1 i t h its DOHCvs engine fam ilies and this outstand ing system w as alsoad op ted fo r th e VH45DE engine. The N VC S system useshydrauic pressureand a helical gear to vary the p hasethe intak e cams ha ft s pro ck et and camshaft lr t a crankan gle ra ng e o f 2 0" ,C on tro l is accomp lis hed by m eans ofa solenoid fitted to the end 01 each intake cam shaft and ahydrau ic pressureoontro l valve inoorpora ed in the. VCS unlt, This ena1> tes the intake valve tim ing to bevaried between two levels. Under h'gh speed and highload conditions when power is needed, the intake v'alveclo sing -m ing is d elayed to keep the valves open tor alonger interval. In law and m idd e speed ranges whereorque is needed, the intake valvesars closed moreQuIckly.S ta ble id 1in g ha s a ls o be en a ssu red by re ducing valv eovel1ap d Uring idling o peration. W rth a f~ed vaJve tim ingsystem , the cams be designed - he sma ler operatingangle and the intake valves closed sooner if 1 0 0 0 ' I - e n oerque is to be im pro ved w ht e nlffintaining id ing stabiJ ity.This invanabty results in a drop in power outpUt (5). The

outstanding power perform ance a the VH450E engineowes.much a the NVCS system (Fig. 8 & 9). While thisNVCS techno logy has mainly been used . h high~perf 01111 an ce engines to date, it is expeetec to findbro ad er .ap plication in tne future as a standard fea ureotengines mounted in comp act an d small -s ize cars.

Fig ..8 NVCS(NISSAN VALVE TIMING CONTROLSYSl iEM.)

Q ' " " " j ) t o ~ , , : , : : ~ , : : , . - . . - 'u ...~' I.' I. v..... T1 o f t I J I ' t ~Q iiIJLA.-.. _ '. b Wf,,jJ:ij:'" ip;..o' ,...q:& ! I - " , . . . . " "

Fig ..9 EFFECT OF THE NVCSA IR IN TA KE SYS TE M D ES IG N-V ariO US possibili iescan be considered for the intake surge tank and intakem anifo ld 'of a V B engine. For instance,a single surge tankcan be employed to feed all eight inaKe manffo ldbranches co lletti eFy,or a dual system can be used in\!','hich separate surge tanks are provided toreach bank.The single surge ank syst.em . w h'ch p rovides unJorm

intake cydes of Sloe crank ange degrees, is moreel'Jec iVe in reductng variation tn charging efficiencyam ong the cylinders. A dualsurg.e tank sys em can alsoprovide unifo rm .intakecycles .180 crank angledegrees), but.ttis so metim es m ore difficu to d es ig n th eman-fold wtth b ra nc he s o f e qu al !Ie ng th..

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The air inlake sysem of the VH45DEengine ha sbeen designed with one surge tank and equaHengthmanifold branches for more even charging efficiencyamong the cyljnders. The intake air resonant point hasalso been set at a relatively high engine speed. Asmen onedearlier the intake manifo ld is buil w ithN is san's aerodynam ic ports fm improved torque in the[o w and m id dle s peed ra ng es (F ig . 1 0).

Fig. 10 AERO DYN AMIC INTAKE PO RT

SOD IUM-C OO LE D E XH AU ST V ALV ES -T he exhaustvalve stems are fil ed w ith metallic sodium to lower theemperatureof th e v alv es and su rr ound ing parts of ~hecylinder head when the engine is ,opera:ed under h.lghspeed, heavy load condl ions. As a result, knockresistance is im provedi and engine orque increases. A nX -ray photo of a sodhm-cooledexaaus vale is shown i,nRg', 11. The e ff ec ts of the sodium COO led \laNes can beseen in Figs. 12 and 13 in com parisonw ith conventionals olid ex ha us i v alv es .

i~ototype

Fig. 11 SOD IUM COO LE DEX HA US T VALV E

Fig,. 12 E XH AU ST V AL VE T EM PE RA TURECOMPARISON

~ ; :: iC O M P f l E 5 . S I O H RAllO: ;

f i iQ U I II tO to 1 4 1 T IO N T 1M I N OFig. 13 EFFECT OF THE SO DIUM COOLEDEX HA UST V ALV E

SMOOTHNESS-An investigation was rnace of hea cc ele ra tio n G ch ara cte ris tics s uita ble fo r a lu xu ry car .was found that a quick an d prolonged G characteristiccan be obtained u nd erw id e-o pe n th ro tH e operation (Rg_14).

1 ~ lT I IA ,E lS IFiO.14 W.O .T . ACCECERAT ION G~TCHARACTERISTIC

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A linkage m echanism has IJeen adopted to provide adelayed thro ttle opening characteris tic hat works toassure smoo th .powerou tpu t when the t r at tl e is partiallyopen.The DUET E-AT system isernploye{j to provideintegrated control 'over the engine' and a u om a n clra nsms sio n. T his s ys tem reducestransmssion shockduring gear sh if ts and integrated con tro l a ls o enables th ecar to start off in second gear without any lurchtng.T hank s to the rorego ing lech lcsl features, th e VH4 5D Eengine can produce as much as 90% of its maximumOf que beginning from 2,000 rpm . They also assuresm ooth deH llery o f am ple IX Iw er up 0 the high speedrange, an output characteris tic w ithout preceden tn thisctassot v a eng ine ( Fig . 15,16,17).

8 'e ~~ 3 2 ~ 4 8 G 6 ~E N G I N E S P E ED I X I O : ;p m )

Fig, 1:5 POWER OlJTPUT OF THE VH45DEENGINE

I N I'l N IT I - - - - - ,( 1 0 1 $ ' - - - - - - i

Fig ..16 ACCELERAT ING PERFORMANCE

' lSOOHC~.61 *

Fig. 17 RATED SPEED COMPARlSONPLE.ASING SOUND CHARACTERISTICS

Veh ic le s ou nd characleristics p leasing to the hum anear are generally typ ilied, firs t o f all, by a linear soundl eve l re la tive 0 Ih eeng in e s pe .e d..Second, th e s oun dlevel of the IDndamen al order com ponent, the fourih~order com ponen for a VB engine, exceeds tha of theother orders. W hen the even and o dd o rd er componensound levels are close, the sound ts p erceived as lJeingim pure and unpleasan . A 1 ' 1 2 order component sound isheard as the so-caned rumbljn g. no is e ( Fig .. 1 8 ) .

. ' J .. .

'

H 8 T H W . O. T A C C E L E R A T I O N/ . M e :S U R E .o A T F R O N 'F S E A. 1' AI A A ..~""=='

~

oFig. 18 EXAMPLE OF RAM BUNG NOISE

P re vio us e xp erie nc e with V6 engine de elopmentindicated that a V6engine ,crankshaft ,hav ing o ne th ro wand tl.vo p in s, ha s le ss IJ en dn g a nd lo rs io nal rig id ity th anan in -lin e engrnecranksha ft because of the 1 -d er s pa nbetw een the journals. In the case of a vee-type engine, iis essen ial to assure high rigid, aro und Ihe block sk[rbecause thecombustlon pressure is imptlsed on thecylinder :b lock diagonally (F ig.19) and tends to causepow erp lanofs ional and bending r vibra on (6). B asad onsuch experienoe, the fo llow ing steps were taken 0achieve p leasing s ound characteris tics for the V H4 5D Eengtns_

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Fig. 19 V TYPE CYLINDER BLOCK DEFORMATIONFirst. the crankshaft is m ade of forged steel and hassufficiently larg.e pin and journal diam eters to m ain"ainn igh th rowr ig d i1y .Setond,at the fran en d of the crankshaft the pulleyincorporates mass damper to reduce cranksha bendingviJ)ration (F i .g. 20).Third, a bearing beam is used t o enhance the ' supportrigjdity:o thecranksllaf t [naddm on, sde bolts have beenadopted and the cy.linder has been reinforced. to

suppress the d iago nal and torsional deformations 0 theb lock . l JilhiCh are unique to a vee-type engine (Rg21).FOllrth, primary-order balancing 's done to reduce therotating,irnbalance hat results in engine vibration. Thismeasure has reduced the imbalance oone-tourth thep revio us lev el (R g. 22).The lig .,.weight o f the pistons also contributes to areduc tion in v il )r at ion .In addi ion :0 re duoing ,eng ine v ib ra tio n, a O r intakenoise has. been reduced ttiroughelaborate tuningmeasures, These include ti1eadop lon ot expansionresonators , He.lm hollz resonators and tube resonators .As a result, th e VH45 0E eng jn e a ch ie ve s p le as tn g s ou nd

qua lit y a nd .lin ea rity h 'om . id tng to the re v lim it w itl1 0u tanys en sa tio n o f p ea ks (F ig .2 3).

r:..; \ l ' . ',. /~~/::_:'i~- - ----~ ,A 16 I~, '~LWI1)(10' I IIFig. 20 EFFECT OF BENDING MASS DAMPER

~_~_._t.2 0 0 mf E O U c " ( H z l

Fig,. 21 H IGH RIGID ITY DESIGN O F CYLINDERBLOCK

1 0 0 0

$0.E N (3F R L fN e.tl..A N Oo ENGAR l J. rf J3A~

Fig, 22 ENG. ASSE MBLY BALA NCING

-W.O.T. I o t e : H 1 .I l & I l 81 t J I I j J NI ~ld

Fig .23 E NG ..V 1B RA liO N FREQUENC Y A NA LY SIS

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RELIA:SILITY ANDO'PERATION MAINTEN ANCEaFREEF irs t o f 8 J I , singte-s rand roner chains,equipped w ith ahydrau tc tensioner,are usee to drive the camshafts fnorder to assure h-gh reJiabilitysuitable to a luxury car.Un ike H mlngbelts, w .hi.ch have com e into g.eneral use inrecent years as cam shaft dri es, these chains require no

ad justing or rep lacing .. R ecent im pro vem ents tn chainsand associated technolog-es have gone along \''1aytoward solving traditional problems such as noise ande xp an sio n (7 ). W h H elim in g belt r n a erials have beenimproved, th e belts still require regular rep acemsmpartic ula rly in high~per fom1ance cars w hich have higherengine comp artm ent tem peratures. T herefo re, chains areregarded as being a m ore suitable dlive system in cars'Nhere a long service life is im perative. Thed-:erence inw'idth between belts and chains also g-ves chain-dl ivesystem s ana er adltSntage in that Ineycancontrtbute toa shorter overall engine length. Th~s can also be.accomplishecl by po sitio ning Ine oil sea] in the spacebetveen U le'enginefro ot co er an d th e c ra nk shaft p ulle y,which results in a more compact encme front end. Forthese reasons it \'/as decid ed to ad op t single-strand ro llerchains as the camshaft drive in the V1-145DE engine(Rg.24).

Second, Ine cross-:flo\!/cooling system is anotherechnicalfeaturecontributing to enhanced renabUiIy. Itprov ides even coonng of each cyHnder. resulting in esscylind .er bo re d isto rtio n. Furtherm ore, it m akes po ssibleun ifo rm com bustion among : t he cylinder s (Figs. 25 & 26)_Third, the issandirect Ignition systern has beenad opted (Fig.27). W ith the m echanical dislributor systemus ed p re vio us lY ,lne s eco nd ary v oltag e ge nera te d by thecoil was distr ibued to the spaffi plugs throughhightension cables. Cons eq ue ntly, ig nitio n en ergy te nd edto drop at higengine speeds.The VH45D 'E engine has a crank angle sensorattached to the end 0' he exhaust cam shaft on the leftbank for detecting the crank angle. The sensor signal Issent to the E CC Sengine m anagem en unit w tlichoutputsan ignillon signal to !he pm ver transistors located aboveth e rocker arm covers of each bank. The powertransiStOrs then send an igni ion signal to the cornoactco ils m ounted each spark p lug. Because of heir oompacslze, the eight co ils charge very qujckJy and are capal)leof p ovid inga stalJle supply of h-gh secondary voltage ot37kvat 9000 rpm . The com bination 0he NDiS systemand pla:tinum ~Upped plugs supports the h'gh~speedperformance of the VH45DE engine and providesm ajntenano e~ free o per.ation w ith no. plug rep lacem ent

required for up to 60,000 miles, .In addition, the hydraulic. lash adlusters m ake valvecreara ce adjuslm ents unnecessary and tile auxiliary airco n r o t v alve fo c idling o peratio n requires no ad juslm entbecaus eU le contro l unit "learns" ho w nuch sup plem entalair should beprovided. The control unit and crank anglesensor are provtdedloVith backup eireuits as a rai l~safem easure in case of trouble_ UQ Uidpacking is used fornearly a J [ engl e seals to assure high l ieJiabUity.

F ig. 24 TI.MING CHAIN DRIVE OF T HE VH45 DEENGINE

Fig. 25 CROSS~fLOW WAT1ER COO UNG SYS TEM

F ig ..26 E FFECT OF CROSS FL OW COO LIN GSYSTEM

_ b . e~l~-Fig. 27 N IS SA NQ IIR ,E CT IGNIT IO N SYSTEM

. . . . . . .

125


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FRICTlON LOSS REDUCTIONRedudng engIne friction is one of the m ost im portantissued in developing a nev.' engine. TIle foUmvingdiscussion ocusss on he various echniques emptoyedo reduce f ricron in the V H450E engine.H olle r ro ck er a rm s v ~e re ad op ed 0 re du ce v alv e tra infric'on, 1A 'hich reportedly accounts for about 1;5% of all

engine l'riclio n. InU le 32-v slve V 1-14 50E engine, the useof ro ler rocker arms has co ntributed 10 a substantialreduction in friction, as seen in R g . .2 8. B ecause frictio nI. 'I8S reduced w ithou t decreasj ng the valve spring load,the range of valve motion was not affected. In theVH45DE engine, the areas of contae between he valvesemend and rocker arm and between the hydraulic lash.adjusters and 1I1e rocker arm, as well as o ther s lid in gsurfaoes,are precision machined to reduce friction.

The piston sldrts are also cooed 'Ih molybdenum.This p rocess in vo lves sp raying the skir t \'j~thmo.lybdenumfollowed by heatnea ment. Th.e tens ile fo rce o f the p is to non ri 9 was also re-exam ined and. m odified. The m ainbea rin g w id th was reduced 0 the neighbom.o od o f 0.3 D,1 .'I he re D: :: : t he jou rnal diameter. The p ow er lo ss in cu rre din driving fhe all pump has osen reduced. by adoptingIn 'V olu te ~s ha pe d ,e xams l s pu r g ea rs in ih .e p um p.

1~9'ml0 . ( 1 5

~O.30.~~ ( 1 .2 5 '~. ,

o~ 0.20 69".$ ..wa 0.15IXoI-IJ J 0.10 .>c :i:li0.05r. J

o -

oil pressure. O . 2 k : _ g ' l o m 2~1I18mj), 7 8 . . . . 8 2 " CW ithout r tl llarroeker e l ' J t l i

~ . . . . . ,E l ch a lJ s i c a m s h a f tInlaKe eirnahaft

~~- ; )1E x h a u s t G &O i I 5 h a r t-- - ------ - - _ . _-5 0 0 1000CAM SPSeD (rpm }

o 1000 2000E N G IN E S P E E D (rpm)

3000

Fig ..28 EFFECT O F ROLLER ,R OCKER ARM(Head assembly)

MAJOR STRUCTURAL COMPONENTST Ilts s ec tio n o utlin es th e majo r s tru clu ra J compon en tsot tbs V H45D Eengine which are shm "i'n in Fig. 31.CYLINDER 8LOCK(Fig.29)-As indicatedearlier,anatum inum cylind er blo ck is m ad e o f a hyp oeutectic silico nalum inum containing 7-10% silicon by v .re ight ,a ma eria

that provides good cost perfo rmance. he structureincludes cast-in iron liners, 3 m m in th ic kn es s.w hich a recast at IQ lw p ressure. Each cylinder has an ind.ependentwate r ja ck et fo r im pro ve d cc(lo!ing and the closed top deckdesign contributes to hig; er reliability. The housings orthe v,ra!er and oil pum ps have been attached directly 0the block to shorten the overall engine length. Coolingw ater galleries are .Io cated betv'/een the lJanks,as is themain 0-1 ga1 le ry . The s id e 0'1 gane~ i s prov ided along theface' of the Ie bank and io"ns Ule m ain gaJe,ry a the rearo f the blo ck . Therfg'dity of the bloc has been increasedby applying rib re in fo rc ements 'b etw een tfle l) an ksandalo ng the s id es . Other m easures taken, to im prove blockrig id ity in clu de he side,~ support structure fo ,: r thebearing caps, use of a bearing beam and the ad op tio n oa large-size ange at the rear whet!e the transm ission isa . ached.

Fig . 29 C YL IN D E R B LO CK

FIg . 30 C YL IN D ER B LOC K126


12/16


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CO NN EC TING R OOS- The connecting rods are m adeof a h ig h- str engt h micro-al l.oy ,ed f ree~cu t fo r reducedengine w eight A n angular tightening technique is usedfo r th e connecting rod bolts and nuts to r educe varia tionin axI al f orce. T he large and sma ll e nd s o t the rods are 55and 22 m in d iamet er, re sp ec tiv ely , and the distancebetween them is 147mm.CRANKSHAFT (Fi.g. 3 3).. Th e tw o-p la ne fo rg ed steelcrankshaft carries six co unterv eights having go od w eightefficiency. TIN O counterw eights are attached; on eitherside of the number one and four pins and on ecounterweight is a tta ched to the front and : re ar of thenumber t w o and three pins, Pins m easure 520101 indiameter and 44,2 mm in 'dth. Journals have a 64 mmdiameter an d a re 26,5 mm in width, The comers of thejournalsare filet roU m achined for higher fatigue sire gtha m atch the .h:igh..po Vo'erand h'gh~ speed cap abilIties o fthe engine .. In addmon, the surface of the cranksnaft .israd' C)- frequencyhardened.

F ig . 3 3 CRANK SHAFT

VALVE TR AIN (Flg.7)~The hydraulic lash adjustersare positioned on ttle ins ide of the camshaft to create avery com pact design and serve to m ake valve clearanceadjustments unnecessary. The contact area betw een thelash adius er and th e ro ck er arm is precisio n m achinedfo r less friction. As another measure for reducingfric uo n,th e ro lle r rocks arms are precision cast of ironand incorporate, need e bearings tha" act as the camonower. The rouer bearings hae an outer d'ame er of 18mm and are 12 mm in w idUl, The valve springs are madeof a nel,V material, based on a hig~strengthsniconchrom ium steel alloy w hose m aterial strenglh hasbeen fu rth er improved. The single springs nave a \\'v 0-level p itC h and p rov id e improved surge resistance tom atch the high~speed o peratio n o f the engine.

CHAIN DRIVE (Fig .. 24}Single~strand ro lle r cha in sare' used asim ing chains and bush chain is used as theoil pum p, chain. The cam sprockets have 38 teeth V lr'hilthe crankshaft sprocketS have 19 teeth. Bolhtypes ospro ckets are made of a slntered steel alloy. Chainten sio ners a re provided fo r bo th banks . .The tensione r 'Oth e ri.g ht bank is built w ith a reservoir so nat all the oidoes not run cu t wnen the engine is stopped. Thisconstruction works to prevent chain slaolm ess when th.engine is started. The chain guide 'On the ension side ism ade of p lastic w hile th e guide on t he s la ck side is madeof stece! with an overlay of b aked on rubber.

LUB RIC ATIO N P AR TS -The c ha in -d riv en 0 [1 pumpoperated off a separate shaft from the crankshaft, Thepump is bunt w iUl iMolufe-shapedextemal spur gears anfnim ize drive losses. In con parison wi1h in te rn al g ea rpum ps, Ihis type o r pump has less co ntact area bet\t;eengears as well as !) e ween e gears. and their housings,which re su lts in re du ce d me ton (A g. 3 4). T heblo wby ga ssystem is fo rm ed by he crankcase and rocker arm coverto assure high reliabflifl; .against oil deterioration. Theshapes of th e oU pan baffle and bearing beam baffle havebeen optim tzedo prevent air from inerm ixing 'til he oidue to agitation of the oil in the crankcase, T he optim izedshapes also work. to preentincreased m ellon as well ason pressure fluctu atio ns d ue 0 oil level changes whenth e c ar is o orn erin g o r in c.lin ed lo ng itu din ally ,

-----.tNTWW. G E A R P U P- e x m u w . S P U R G i1 0 R P U fI .P ,..'

2 0 0 0 ' O i J D 6001)P U M P S P C EO lr p m )

Pig. 34 OIL . P U M P CHARACTERISTICS

12 8


14/16

INTA KE MAN!I.FO lD AND SURGE TANK~The intakemanjfo ld and surge tank are made of cas' a um inum .Branches from the surge tank to the in take manif old havea dlarnster thai gradually tapers from 46 to 42mm toassure both amp le low-e nd torque and h ighsp eed p ow eroutpul Each .b ranch has an e qu al le ng th of about 420ro m. The intakem anrtold gaskets are m ade of meta l w itharuJ)ber co aling and are entirely free o f as besto s.EXHAUST MANIFOlD- Theexnaust manifo ld ismade of stainless seel pip ing to reduce the engine',:v eigh. Im pro ved therm al insuJ atio n and no is e iso latio nhave been achie fe I > y placing a coer around the pipingto from a double -la ye red construction. A pre-catalystispositioned at the exhaust manifoldoutle to im pro veexhsustem s sio n perfo rmance.

'ENGINE CONTROL AND FUELING SYSTEMThe VH45DE is equipped ttl fully s equential fuelinjection for all 'eight cylinders. issan's ECCS enginem anagem ent system and a m ultipoint in jection system .The fuel injectors are otme tottom feed type w 'hichp rov idessuper to r hea t res is tance. The a ir fl o" ,'1m eter is of1he hat-film type and emp!oysan axial~flo measuringecnnlque. Em iss ion con tro l isacee rnp lis tr ed by m eans ofa three -w ay catalyti.c converter, clo sed ~lo op lam bd acontrol a d exhaust gas rec.irculation. S eparate Ian Jdacontrol is provided for each banI< , w ith both bankequipped wfth an 02 sensor. The 8-1>itECa control unlhand es all control functions, inclUdIng, a ir ~ fuel ra tiolearning control for each cylinder bank. It also providesig ltien : im tng co ntm l,knoeJl control, auxiliary air valveleam ingcontrol, three-way speed control a the fuelp um p, a nd in eg ra te d' e ng in e a nd a utoma tic tra nsmis sio ncontrol (Rg. 35). .

w . . .. . 1!cks are a~ made ovariablltty in the comb us 'on chamber volume, fueinjector 11010vate and other parame e rs aifedfng ,enginperformanoe. .

(0 .\l1II1I.naWi.d . n . ~

Fig. 35 ENG'INE CONTROL SYSTEM THE VH45DH ENGINE129


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CONCLUSIONA pp ro xim ately th ree yea rs w en t in to th e d ev elo pm en tof the V H45D E engtne m ounted in the N issaniN FIN I.T IQ45 sporty IllxUry car the was recently put on themarxe The VH45DEincorporatesan a rra y o f a dv an ce declmologies issan has aceemutated to date tndevelop ing, high-perfo rmance enginesindud ing arnultivalva design, v aria ble v alv e tim in g,e le ctro nic c on tro l

and so phisticaed m easures for assuring develo pm enttarge~s set or the ne~'" engine w ith regard top erfo rm an ce , p le as in g s ou nd C lu altty , re ia bi.!ity an d fueleco no my. O ne key to the SLiCCesS of this pro ject w as theIh e pe.ople involved in th e d ev elo pm ent wOEk constantlyhad their s ights seton achieVing challenging targets.Another im portan factor was that Nissan's engineeringc ap alJ ilitie s a nd a na ly tic al to ols w ere p ut (0 rn anmum usein designing all he engine p arts . R na rly , the useotSimultaneous engjneering made i p os sib le to tra ns la tehe des igns in to c oncre te products w ith good e ffic ie nc y.This paper has only p resented a brief OUUineof theconstrue on and features of the VH45DE 'engine. Thisne"/~generati.on v a engine (Rg. 36) will stand out in the

long history of the v a pOlu erp !a nts fo r its ability toge ne rate p ow er ln respo nse to the d river's I ,v ishes overIhe entire speed range from id ling to the rev lim . Thecom fortable , p le as ing performance it im pa l1 so theI FIN1TI 045 w ill surely give the owners of this newsporty luxury car the h ighes t level s a. satisfaction.In future work theauthors11 continue their effo rts todevelOp new an d improved engines that meet theChanging demandso fi.h e ma rketp .la ce .

ACKNOWLE,DG M .ENTSThe authors would Ilke to express their .appreciationfo r betng given this opportunity to introduce the ne NVH45DE engine. The development o f this new engineowes much 0 the enormous e ffo rts an d enthus iasm ofmany people in N issan's R&D divis ion both inJapan andoverseas as well as in the manufacturing, sales andpublic relations departments. The successfuld ev elo pm en t o f th is h ig h..p eJ iom 1anc ee ng in e d ep en de dto a great extent on their hard work and we:alth 0e xp e.rle no e,e ng in ee rin g s kflls a nd e xp s 59. The aut ho rs1j!lould n k , e to ake thIs o pp ortun ity to th'ank everyoneNithi,.. and outside theoo mp any w ho co ntributed so m uchto th e d ev e o pm ent, rnanutacture and ma rketin g pub lic it yor the new V H45DE engine.

REFEREN.CES1. T.Okuno etal., -Devel.opmento f a New 12 valve 4cylinder Eng in e- SAE Pap er 8 8 17 76 .2. S .N is himu r.a e t 31.. "Nissen V6 3..0 Ulre, -cam 24Va lv e H igh Pe rfo rmance Engine- S AE P aper 870351.3. YJshida e aI., "N issan's New In~Une OOHC SixCylinder Engine and Its Deveropmen SAE Paper

860160.4. K.Sasaki et at, ~A New 3.0L V6 Engine Developed bytssan M o'to r C om pany- S AE P ap er 8 40254 .5. KMaeka\'f'a et al., " Development 0 a V alv ,e T im ingCon Iro I S ystem - S AE P ap er 8 9068 0.6 . H .USU) 3 at al., -low noise D esign for M ain S bucturalParts o f V~6 Engines" Journal O f the Soci.ety oAutomotive Engineers of Japan 1987 VOl 41,10.7. KMaekawa et at, ' 'The Cam shaft D riving System bylim ingchan and , . e 'lmproved Technology." Jo m alof the Socie ty o f Au tomo tiv e Engineers of Japan 198 9Vol 43.9.

1.30


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Positions and opinions advanced in this paper a rethose of theauther(s) and not necessarily those ofSAE. The author is solely responsible for thecontent of the paper. A process is available bywhich. dIscussions will be printed with the paper i fit is publ.ished in SAE Transactions .: Forpermission to publish this paper in full or in part,contact the SAE PUblications Division.

Persons wishing to submilpapers to beconsidered for presentation or publicationthrough SAE should send the manuscript or a 3'00word abstract of a proposed manuscript to:Secretary, Engineering Activity Board, SAE.

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designing the nissan vh45 engine-information

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