Leylandr--. - . ·-1&~

)~~~

i Special Tuning

for the

MIDGET and SPRITE1275 c.c, ENGINES

C-AKD 509.8

Issued by: BRITISH LEYLAND SPECIAL TUNlNG DEPARTMENtABINGDON ~ON .. THAMES • BERI(SHI RE • ENGLAND,-,

SPECIAL TUNING

Model !"UrGET III &. SPRITE IV 1275 cc

DESCRIPTIVE INDEX

DAIA

ShMt Ea - 1 laue 6

DescriptionBODYWORK

Bonnet securing strap setRubber Toggle Strap setHeadlamp Cowl Kit

BRAKESDS11 Brake pad set (competition)VG 95/1 lined brake shoes

CAMSHAFTSRoad 160

, 560

510

210, Lift .250"

o 0' 0' °Rally 10 , 500" 51 , 21 , Lift. 250"Racing 50°, 70 ,75° 45° Lift .315"Super Sprint _ 60° 80° 85°' 55°; Lift .315"Sprint 60°: 80°: 75°: 45°, Lift .315"

CARBURETT,ER14" Twin SU AssemblyInstallation Kit for C-AUD 194 CarbsFlare pipe for 1-t" SU Carbo alloyli" Twin SU AssemblyInstallation Kit for C-AUD 416Flare Pipes for 1t" CarburettersAir Cleaner 1t" SU CarbWeber 45 DCOE 13Installation Kit and manifold for Weber

CRANKSHAFTCompetition Nitrided Crankshaft

CLUTCH &. FLYWHEELLightened flywheelCompetition clutch cover assemblyCompeti tion clutch driven plate

CYLINDER HEADRace Extra Large ValveRace Large ValvePolished 19cc

DISTR.IBtrrORCompetition timing (Lucas 41110)EXHA~ST SYSTEM

Competition large bore manifoldPINAL DRIVE &. AXLE SHAFTS

3.727 ratio, matched crown wheel & pinion3.9 ratio, matched crown wheel & pinion4.22 ratio, matched crown wheel & pinionLimited slip differentialAxle shaft, heavy duty, Disc wheels onlyAxle shaft, heavy duty, Wire wheels only

GEARBOX

Straight cut close ratio gear set complete '

Part No.

C-AJJ 3381C-AJJ 4016C-AJJ 3385

C-MIT 16C- 8G 8997

C-Am 567C-Am 542C-AEX; 529C-AEX; 595C-Am 597

C-AUD 194C-AJJ 3334C-AHT 247C-AUD 416C-AJJ 4001C-AHH 7209C-AHT 210C-AHT -14 3C-AJJ 3360

C-Am' 326

C-AHT 70C-Am 546C-Am 547

C-MiT 22'1C-AHT ' 222C-AHT 134

C-27H 7766

C-AliT 11

BTA 535BTA 1223BTA 539

C-BTA 1226C-BTA 940C-BTA 939

C-AJJ 3319

Qty/Car

111

12

11111

1'1211221'1

1

111

1

1

1'1'1'122

'1

,Sh e e t No.

E-5E-5E-5

E-5&-5

£-2/2-'2&-2/2-2£-2/2-2E-2/Z-2E-2/2-2

E-3&3&-3B-3&-3&-3B-3B-3E-3

E-4

E-3E-2B-2

&-1E-1E-1

B-2

B-2

E-4&-4E-4&-4E-4&-4

E-4

'M'OIltTANTI Tllnlnl of 1M kind d-.crlbed 011 thlt .h_ Is ..p~lr acclttMd by dl. W- of u..Warnntv ol th. ".hld• ..,anufartur.r_

1275c<;

6IssueE - ~

Model t-ITDGIT III & SPRITE IV',

Sheet

SPECIAL TUNINGDATA

When carrying out work on these ca r s always refer re" Workshop I";Cl:,.ui'll AKD 4C21.

Cylinder Head - Stage l

Remove all frazes from th~ combustion chamber and ports, bUe leave the locatingsleeves in place when matching the manifold ?orts. The c0mpr~ssion ratio may beraised by machining the head face, .012" is approxima tel y equa 1 to 1 cc reductionin combustion chamber volume. Exami:1e the \"atecv."~ys to er.sure that there are nocore wires remaining. Use the competition cylinder heed gasket C-AHT 188 andensure there are no burrs at the base of the head studs by reMoving the studs andcounter sinking the holes. A lightly polished standard cylinder head C-AHT 134is available with 19cc combustion chamber (9.S~1 retio).

Stage 2 Road Tune (9.5:1 ratio)

A large valved polished and gas flowed cy.l i ndcr \-]~cG ano ccmp-",tit:.t :"n h('ild gasketshould be fitted in conjunction with a speci.a l cllstrib\.;tor, tv:in H" SU carbun:tters,special inlet manifold and air ~ l e ane ~s which a~e contained in the co~burp.tter

installation kit and a free flow exhaust manifold w~i~h shou~d be coupled to astraight through exhaust system.

Description

Cylinder HeadTwin it" SU carburettersInstallation Kit (carburetters)Distributor-N64Y Sparking PlugsGasket (Cylinder head)Exhaust Manifold

Part Nc.

C-AHT 461c-xun 640C-A.JJ 4040C-27H 7766C-37H 4208C-AHT " 188C-AHT 11

Performance Figures (By kind permission of "Motor" )

Acceleration through gears from rest

M.P.H. Km.P.H. ~. Stage II---0-30 0-48 4.0 sees 3.3 sees0-40 0...64 6.5 5.10-50 0-80 9.3 7."20-60 0-96 13.5 10.00-70 0-113 19.1 13.80-80 0-129 28. ~ 1E.80-90 0-145 45.7 27.5

Standing quarter mile 19.3 17.4

Acceleration in Top Gear

M.P.H. !<m.P.H. Std. stage II

20-40 32-64 9.9 sees B.9 sees30-Sb 48-80 9.E- I}. Q40-60 64-96 9.8 8. 550-70 80-113 11.7 9.160-80 96-129 16.0 10.970-90 113-1.45 14.0

Maximum Speeds

Flying lap 9S map.h. 153.0 km.p.h. 102 m.p. r.. 1f,4 km.p.haFlying quarter mile 97 m.p.h. 156.0 km.p.h. ~'J4. 7 m.p.h. 168.5 km.pah.

Issuad by: BRITISH LEYlAND SPECIAL TUNING. DEPARTMENT

ABINGDON ..ON .. THAMES' BERKSHIRE • ENGLAND

SPEC;AL TUNING DATA

ModelMIDGET I II & SPRITE IV I 1275cc Sheet Ea - 2 Issue 5

DESCRIPTIVE INDEX (Cont'd.)

dia C-Am 544:naterial C-AEG ~69

C-AEG 39 ?C-AD3 399("-Affi 519C-Affi 578C-/J.EA 6 52C-AEA ~24

C-AEA 654

C-AHA 7573

Descriptio::,LIT£RATURESpecial Tun ing Book et - 1275cc Midget/5p~ite

Special Tun ir.q Da t a Sheet Set - all mod~ls

Bi~der, f o r Speci a l Tuning SheetsDivider- s e t :or Binde rBritish Leyland Special Tuning Emblems (1 pair)British Leylar.d ~pecial Tuning Lapel Badge

OIL COOLEROil co~ler k ~ t co~plet~

Oi ~ C~ol er ~xt~a I cg~ ~adi t o ePISTONS

SUSP ENSI ONShock ahs o r b e r , compet.i.t.Lon setting front

frontShock absc rber I ed jus t ab l a rear

rear

E-1E-l£-1E-1

£-3

E-2£-2E-2B-2

&-4&-4E-4E-4E-4£-4E-SE-5£-5E-5E-4

E-5

E-2B-2B-3£-3B-3E-3E-2E-2£-2

1 E-31 E-3

4

111

1

1 £-5

1

4

5

l

818B8

- I111211

Qty./Car Sheet No.Part No.

e-AXD 5GJ3~-AJJ 3333C-AKD 5061C-!U<D 5093C-AKD 5125C- AHT 200

t:.-AJJ 3323ARO 9809

C-AEG 043043C-AJJ 338243C-AJJ 338223C-AJJ 3377

C-AJJ 3324

C-37H 4208C-27H 5982C-~7H :;::1 :~ 9

C- 3Tt-! 2148

C-AHA 6451C-AHA 6452C-AHA 7906C- AHA 7907C-AHA 8272C-AJJ 3322C-AJJ 3314C-AHT S6C-AH'F 57C-AJJ 3356C-AJ.J 4031

R.H.L.H.R.H.L.H.

IICo..,peti t i.on 4 !:'"i 9 fl a t top, .j.. 040" "Flat top f o .:'ged · 040"Fla t top _'orqed +020"Lightweight forged di shed (9.75:1) set(~tate s i~e required)

SUMP-Deep sump and oil pick-Up kitSPARKING PLUGSChampio: ~ J E41'

S7RN6 2R6.~Y

Lower~d reflr r Oed s pri ngsFron~ suspen~ior, lo~ering kitAnt i-col1 b a r kit comri l et.e 9/16" df.a,Anti- r o l bar ~ " dt a . ·An t i -;:" · . b a r - 1 / 16 " ciaIns t a Ll.a ion ki t f o r C-AH'I 56 and 57Rear ~~~p stop k ' t

VALVE G£AR.lnlet varve - l : r ge i . 406" (35. 7%, )Inlet v;;\lve (zt:.~. s i zr-' .::ompet.i~:iol :

Valve rocker s~acer

S t r ergthened r ocx e S!"l 'i f:Lig' t.en ec tappp'Camsha t p~ -e t - ~ ~~ t erce =Val ve spr i ng - i nne r

- o u terlac ting collar

WHEELSWire, 60 spoke 13" x:;"

•

Issued by: BRIT-1SH LEYlAND SPECIAL TUNING- DEPARTMENT

ABINGDON - ON-THAMES· 8ERKSHI RE • ENGLAND

SPECIAL -rUNING DATA

• IS(

Issue 3Sheet E - 2ModelMIDGET III & SPRITE IV, "1 275cc

Camshafts

All camshafts fitted to these models use flange 12G 729 f or the staroil pump drive. They are not knterchangeable with the conventional-PinDrive Op Pump type. _

For road and rally use with emphasis on mid range torque the C~AEA 567camshaft will be suitable.

For racing purposes C-AEG 529 has increased valve lii;'t • 394" (l~) andopening period while two new ca~shafts for short circuit or sprint work arealso available with even longer periods.

For complete camshaft specification -refer to sheet Z - 2.

Distributor

Distributor C-27H 7766 is available f o r use with the above camshaft,' moststages of tune require static setting of T.D.C. Maximum tune may require 1

0or

20 A.T.D.C.

Valves

The standard inlet valve can be replaced by C-AEG 569 in i mp r oved materia1. ­A large diameter inlet valve C-AEG 544 1.401". (35· 7%) is also available.C-AEG 544 is fitted to the competition cylinder head C-AHT 22 2.

_The stem lengths of these valves are longer than Cooper '5' and they are NOTinterchangeable~

Valve Springs

8 off8 off8 off

C-AEA 652C-AEA 524C-AEA 654

Valve Spring InnerValve Spring OuterBottom Collar

'St andar d valve springs suffer valve crash around 6700 r.p.m. without causingundue load on the valve gear. Stronger (180 lb.) springs ~ay be required forcompetition, these raise valve crash -to around 8300 r.p.m. with the C-AEG 529camshaf t.

The locating collar C-AEA 654 must be fitted with high lift camshafts toprevent valve springs becoming 'solid'.

Plugs

For ra l ly or road use N64Y (C-37H 4208) will be most suitable. For racingit will depend on various factors, but NS7R (C-27H 5982) J N62R (C-37H 2149) orN60Y (C-37H 2148) cover a suitable r enqe , _

Exhaust Manifold

A competition 'large bore exhaust manifold, C-AHT 11 can be connected to alarge bore sileocer with tail pipe terminating in front of the rear wheel fortrack use, or it can be connected into the existing exhaust system for rally/roaduse.

Clutch

A competition clutch is available, cove r assembly C-AEG 546 has a strongerdiaphragm spring and shoul d be fitted with driven plate C-AEG 547. For very highlytuned power units a special clutch may be required, if lOS b.h.p. is likely to beexceded.

Issued bv: BRITISH LEYLAND SPECIAL TUNING OEPARTMENTABINGDON-ON-THAMES • BERKSHIRE • ENGLAND

SPECIAL TUNING

Model MIDGET III & SPRITE IV, 1275cc

Sump

DATA

Sheet E - 3 Issue 3

"" .~ .~

• . <

.-. '"

Where oil surge is exper~enced in competition it is r ecommended that a De epersump, with repositioned oil pick up be fitted. These are contained in kitC-AJJ' 3324~

Oil Cooler

If the car was not delivered with an oil cooler a comp lete ki t is availableC-AjJ 3323. For racing use ~he larger capacity cooler A'R.O 9809, but this wi 11slightly restrict sir flow to the radiator and must be carefUlly positioned.

Carburetters

Twin 1'1" SU carburetters are available C-AUD 194 and should be fitted 'wi t hInstallation Kit C-AJJ 3334., This kit contains all necessary gaskets, stUds, e t c .

Flare pipes C-AHT 247 may be fitted to restrict blow back and air cleanersC-AHT 210 are also available for normal road use.

Weber carpuretter (twin choke 45 D.C.O.E.) C-AHT 143 is available to suit arace tuned engine. ' Other uses may r equire different chokes or ~ets.

Fitting kit C-AJJ 3360 is complete with manifold for the Weber and containsall the necessary parts required.

Valve Gear

A strengthened rocker shaft C-AEG 399 was fitted in production from EngineNo. 12CC/Da!H16597, using modifi e d rocker pillars 12G 1926 and l2G 1927. ThepU lars must be located correctly to maintain the oil supply and l,oc a t e the shafL

Friction between ' t he rockers can be reduced by replacing the co'I I springs witJ­sol i d ~pacers C-A~G 392 (3 off). ' The standard r0cker 12G 1221 can be f urtherl i gh t ened by carefully grinding the sides of the pad and bosses. Ensure correctpositi~ning over the valve by using spacing washers AEG 168 or s lightly machiningthe pillars.

A specially lengthened adjuster screw should be used with Race. Sprint orSuper Sprint ca5hafts, Part No. C-AEA 692.

Fl.ywheel

A special ly ligh t ened flywheel C-AHT 70 is available weighing 12.5 lbs.(5·67 kg.).

This must be balanced with clutch, crankshaft and damper to ensure perfectbalance.

' ,Li ght ened Tapp~ts & Sprocket

Special tappet C-AEG 579 are available that are lighter than sts0dard thusreducing the l oading on. the camshaft and raising the valve crash point.

A lightened s t ee l camshaft sprocket C-AEG 578 is also available~ This isNOT suitable for B Series engines as timing would be incorrect.

, 11" HS6 SU carburetters C-AUD 416 can be fitted with the fitting kit" ~-AJJ 4001 which includes manifold and f lare pipes •

' I ss ued by: BRITISH lEYlA'NO SPECIAL TUNtNG DEPARTMENT

ABINGOON~ON~THAMES • BERKSHIRE' ENGlA,NO

,SPECIAL TU'NING

Model MIDGET ' III & SPRITE I V , '1275c c

DATA

Sheet E - 4 Issue 3

-

Gea'rbox

C;Lose r atIo s t!'?l l-Jht cut gear set C~AJJ 3319 is available fo r fi tUng direc t'into these gearboxe5 ,and nIl the necessary joints and lock washers are includedil1 th'is k it '~ 'hi c h giv.es t he following ratios:

,...

1st::'nd3l'd

C!R

2·5731.7221·255

see,

3· 21.921· 36

Ensure that the latest Laygear 22G 673 is fitted when installing these clcseratio .gea r ~ .

Axle Ratios

The fol~owing altc~na~ive axle ratios are available to fit these cars

3·7273· 94 · 22

111

11/41 teeth10/39 teeth9/38 teeth

Crown wheel & pinionStandard {late carS )Stan~ard (early cars )

BTA 535BTA 1 223BTA 539

Limited Slip Differential

When regulations permit the use of a l irni.Eed slip differential a Powr-Loktype is available, C-BTA 12 26 which may be used with any of the above axle ratios.

Axle Shaft

Stronger axle ::::J lfl J. : , ' C- iU A 940 are available -for competition use on carswith Disc Wh~els only II.': ::;ha'fts C-BTA 939 ' are suitable for cars with Wire Whee1s.Ensure that the wheel h<::arings are in good condition when fit ting new shafts.

Front Susp,ens ion

The, -f r on t suspc.r.s ton may be lowe red slightly by changing to the softer frontcoil springs Part ~c . 2A 4214. Alternatively, or i f the car is to be loweredeven further, use t h e lowering kit C-AJJ 3322 'whi c h contains a special packingfor the rebound stops. The standard front springs AHA 8003 give the greatestride heigh t ,

Rear Suspension

A lowered rear read spring 'C- AHA 8272 is available to be used in conjunctionwith the lowered front .suspensi on.

Shock Absorbers

Front shock absorbers C-AHA 6451 R.H. and C-AHA 6452 L.H. are available,wh~ch have a harder setting. For the rear use adjustable shock absorbersC-AHA 7906 R.H. and C-AHA 79D7 L.R. These can be adjusted atter f i t ting toobtain the des ired damping. "

Before fitting the shock absorbers, they should be mounted in a vice andthe arm opera t ed on full stroke for a few minutes to expel any air, from the va lve.

If large capacity fuel tanks or heavy loads are carried, also for towing,i t is recommended that the special rear bump rubbers are fitted C-AJJ 40,3],.

5IssUB

KrooE'T III & SPRITE IV, 12 75cc

E ... 5

ModeJ

Sheet

SPECIAL TUNINGDATA

Anti Roll Bar

When a new car Ls ordered wi th an anti roll bar it is £i t ted wi th one 9/16" (14. 3%>dia. but if the car was suppliec wi~hout a roll bar it may be fitted afterwardsus i ng kit C-AJJ 3314 which cont _ns all necessary parts and fitting instructions.

For competition use two l a rge~ aiameter roll bars are available i" (15.~) dla.C-ART 56 or 11/16" (17.~) ella. C-AIiT 57. These will fit straight onto carsal ready fitted with a works rol l bar . but installation kit C-AJJ 3356 will berequired if no roll bar has previously been fitted.

WheelsWider ~im 60 spoke wire wheels Part No. C-AHA 7573 are available.<330.~) dia. with 5" (12~) rims ...

These are 13H

The latest Rostyle .whe e l Part No. AHA 8892 which has a 4t" rim can be fitted toearlier cars with disc wheels providing the latest hubs Part No. BTA 1254 are fitted.These can be identified by a grove in the periphery of the wheel mounting flange.Wheel nut torque must not exceed 45~b.ft. (6·.2 kg.m). Contact tyre manufac=u:: 1' ::

direct for all tyre recommendations but note that great care must be taken if anylarger wheels or tyres are fitted. The front brake hoses must be regUlarly chp.cr.edand it is essential to ensure that the brake hose is well clear of the tyre.

Bonnet StrapsTo eiIminate any possibility of the bonnet flying open during competition events ,leather straps as supplied under part number C-A:JJ 3381 should be fitted. Allcars competing in International competition events must have a supplementaFYlocking device such as the leather straps fitted to the bonnet and boot lid.

: 1,

BrakesCompetiHan Ferodo 0511. brake . pad set C-AH'l' 16 1s recommended for competition US(~,

togethe,r wLt)'l: VG 9~/1 rear brake linings C-8SG 8997. :Us e only LQckh'eed Serie:s II .Disc Brake Fluid for flushing or topping up.

Special Tuning EmblemsBritish Leyland Special Tuning self adhesive emblems are no w available in pairsunder Part No. C-AKD 5125. In vinyl material they are practically indestnlctableonce fitted t o a smooth flat surface.

Head1amp CowlsThese fix direct to the headlamp rims and protect the light units from stone damageetc. Part No. C-AJJ 3385 ( 1 pair).

Alternator FittingA special bracket C-AHT 32 is designed to take t he increased loading when usingLucas 11AC alternator 13H 2131 in place of the existing dynamo. This will copewi t h extra l i ght s or con tinual stop-start motoring where the dynamo outpuf maynot be adequate.

Issued by: BRITISH LEYlAND SP£CIAl TUNING DEPARTMENTA81~GDON - OH-THAM£S • B'ERKSHIRE • -ENGLAND

SPECIAL TUNING

MocIllMIDGET III & SPRITE IV l275cc-

DATA

-S1f••~E- 6 IdUI 2

AXLE RATIO

Axles fi tted after Austin Healey Sprite Car No. HAN7~2473l and 'MG MidgetGAN2-l6l83 have changed pinion bearings and redesigned differential assembly.While the complete differen· .a1 assemblies are in.terchangeable between early andlate type axles, crown wheel and pinions 'A' are" NOT interchangeable.

The different ial cage ATA 7036 (illus. C) remains unaltered and ALL axlesaccept the Limited Slip Differe~tial C-BTA 1226.

CaW. & P. Carrier Assy.....

INo.of Part No. Part No'. DifferentialRatio Teeth Illustration A Illustration B Assy. Part No. Standard Model I

3·727 11/41 ATA 7240 • ATA 7167 BTA \~ 5 l Riley 1·53·9 10/39 C-ATA 7354 • ATA 7167 BTA r;t~2

4·22 9/38 ATA 7266 ATA 7032 ATA 7326 • Up to I4·55 9/41 8G 7129 ATA 7032 ATA 7093 Morris t ton Van4·875 8/39 C4 no ATA 7032 2A 7230 A35 Van5·375 8/43 ATA 7040 A..TA 7032 ATA 7073 • Morris GPO Van

3.727 11/41 BTA 535 BTA 549 BTA 551 Later Riley 1· ~

3·9 10/39 BTA 1223 BTA 549 BTA 1222 Sprite/Midget 04·22 9/38 BTA 539 BTA 549 BTA 550 From I to 04·55 9/41 C-BTA 816 • BTA 549 ATA 7093

• Information only. No longer available ,I Sprite/Midget Change Point HAN7-247~/GA..N2-l6183.....~ Spr~te/Midget Change Point HAN9-~6226/GAN4-77591

f

ILeyland~~ Data

Model GENERAL Sheet z - 1 Issue 7

...

r-.

The following information is issued in order to =acilitate the choice of asUitable final drive ratio and tyre for any particular application.

The table indicates the wheel revolutions per mile for various tyre sizes. fror.this the vehicle speed per 1000 engine revolutions per minute can be calculatedusing the formula:

M.P.H./1000 R.P.M.60,000

or K.P.H./1000 R.P.M. 96,560-A x B -A y. B

where A _ Pinal Drive Ratio :1B - Wheel revolutions per mile

This formula gives the speed in direct top gear only but the equivalent roadspeed in any intermediate gear can be calculated by dividinq this by the gearboxgear ratio.

Tyre Size & Type Wheel revs Tyre Size & Type Wheel revs(Dunlop) per mile (Dunlop) per mile

520 x 10 C41 1058 145}530 x 13 CR82 96514 5 x 10 SP 1095 155/530 x 1.3 CR82 960520 x 10 CW44 1060 185/550 x 13 CRB2 904500 x L1D R7 1053 • 175 SR x 13 MS MK11 865145 x 10 SP44 1080 17.5/70SR x 13 SP44 910

I 195/70SR x 13 SP44 862550 ~ .... CP41 960 I 195/70SR x 13 MS MKl1 865x """ ,145 x ~2 SP44 974 j 205/60 x 13 Rally Super 934let:: X ~2 SP 960 I 185/70SR X 13 MS Type 564 890..J ~ I

"550 x 12 CW44 955·175 x 12 SP44 959 520 x 14 ,C41 865155/500 x 12 CR89 1013 550 x L14 R7 807 •

560 x 14 CLl! 853520 x 13 RS5 914 590 x 14 ~S 842520 x 13 C41 917

d 590 x 14 C41 831560 x 13 C41 884 14? x 14 SP 892550 x L13 R7 840 • ! 155 x 14 SF 873590 x 13 RS5 871 165- x 14 SF 854590 X 13 C41 867 i 185 . x 14 SF 821I600 x L13 R7 807 • ' .

145 x 13 SF 934 550 x L1S R7 775 •165 ;.: J3 SP 892 560 x 1S C41 814560 x 13 MS MK11 855 590 x 15 RSS 807560 ·x 13 MS Snow 851 590 x 15 C41 803600 x 1.3- MS Type 564.869 I 600 x L1S R7 747 •17 5/ 550 x 13 CR65 I 917 ·165 x 15 Sp· . 820. I

For further information contact the tyee manufactu~er5 direct.

Any change in final drive ratio or tyre size wi 11 affect the accuracy of thespeedometer and odometer, which should be recalibrated by the instrumentmanufac turer •

Ail wheel revs per mile are at 30 M.P.H. except those markec • which a~e at~ 100 M.P.H.

~ ......

I Leyland..::b'£l Data ]Model GENERAL Sheet Z - 2 Issue 13

The following chart shows details of camshafts produced for 'A' series in-line•

.,.. 0

~ r s ..

~~- u

~e,.

i~ ~

'" ..'" :..~ ::l.- ~ :

tI, .'" '" j'" ...v- I ... U C

;--. Ii -Ii b't:!l'Q."E-

I .. "I'''(J

.. f ._

~ ~ sl..

~.

t ... ...~- ~ a.

'"

~I ....... t

~ ..a:

.,

e­

'"'"

N ,.. --"',.. z, cI

,.."''''

lil ,,0< i?N ... •

;; s.. tr.:: ~ •" ~Ii " .. »i1 "" " .' "~ ~ J> ""0 :s e...

~ " 1~ .:;• I .. ..0. .. U '"

~:.:>

~ . l i:~

la - t liS" "... «

'" -a...i?~2 ~

~ .8.8~ J~

~~

~~ s..~ ::u

I; ... ~ "~0I; • .. 'f

z r ~ ! ~I of~ !': 3 ~ ~

t, ...

-Par identifi~ation see markings and carn lobe width <-i" .. 9. S?', 11t = 12.7%)

. .+

For cneckfnq , set rocker clearance to .019"For cnecktnq , set .rocker clearance to .016"

(.4&%)( .40%)

NB. See P.C.M.~. Michroform Parts List of appropriate vehicle for fulldetails of changepoints.

Data~l[Leylandb£JModel" GENERAL Sheet Z - 3 Issue 80

" 0".

Overheati.ng

Assuming that the c~·'!.inder head gasket is not lea1<ing due to distorti·:)D andthcT. the correct s parki.nq pl:.rgs, i gni t i on timing and mixture are being useo , checkthe running temperature with an a=curately gro.c-.:ated gauge. Note the ~0iling

points under p~ssu~e - 5 lb/sq.in. 226C

F , 7 lb/sq.in. 2~2oF, 13 lb/sq.in. 246°FC'.nd r efer to the pressure on the cap. If excessi·...e temperctures are confirmed,possible cause may be found amongst the follo"~ng paragraphs, but overheatingin tra£fic can often be prevented by opening the water valve and running theheater so that this acts as an extra radiator•

Examine bottom hose on 'A' series engines in case heater outlet portion protrudes ·into the main bore. Cut off suc)lus with a sharp knife or replace if there isany sign of flaking. The water pump should be checked to ensure clearance betweenvane and body is no more than .020 to .030in. (.508 to • 76~) ... The water pumpintake bore should be as large as possible and the grinding of a slight taper intothe bore will also assist flow. Ensure fan belt tension is adequate. A largerwater pump 12G 1771 was fitted to the la te Cooper I S I models and the 1275 GT, thismay be fitted to earlier models after grinding away part of the block casting toclear the pump rotor. A new bottom hose 12A 1550 MUST be fitted at the same tilne.

If existing thermostat is working correctl~, it ~~y b~ better to fit a colderoperating one, such as 13H 3727 (74

0C,165 r i , Whe.'1 thermostat is zemoved

altogether it is essential to blank thermostet bypass, using sleeve kit G-AJJ 4012.On 'A' series engines, the bypass connection bec~en head and water pump may besealed.

After continual use in dusty conditions, the radiator core may become partiallyblocked with leaves and insects. This can be cleared by compressed air Or ajet of water used in the opposite direction to normal air flow.

Obstructions to air flow, such as badges, extra lights and rally plates can allcause overheating, and should obViously be reduced as much as possible. If asump guar~ is fitted, it is essential to use a large capacity cooler, andthis is also desirable for competition or motorway use. On the Mini range usea cooler such as that contained in kit C-AJJ 3309. On the Clubman range use kitC-AJJ 4030. Full details for oil cooler installations are shown on the M.G.B.Midget and Sprite parts micro film but a larger one is available part numberC-ARO 9875 for the M.G.B. and ARO 9809 can be fitted to the Midget and Sprite.

On the Mini r~oper 'S' ~~e radiator efficiency was improved by changing from13 gills per inch (25.4;4) to 16 gills per inch (25.4%). Tl~is may be checked

'h y count.Lnq vertically the number of horizontal f i.ris in Cl given height of the=adiator core. The ~atest Part No. ARA 2064 ~JST be used with the correct capARJ.. 2'161 and improved top hose 12G 1164 on the'S I only. This same radiatorand cap can also be usee. on the E>iini Coope.r , but cop hose. 12G 104 must be used.For very severe conditions, an auxiliary radiator may be fittec to the Mini rangeusirg"~it C-AJJ 401~. .

For the 1"'tini range, 6 bladed fan 2A 998, Stiffener 2,". 803 :::~re the most efficient.{or ~ooling. T~1 11 bladed Plastic Fan :2G 1305 is quietest, but for racingt or .2-- bladed Fan C-2A 997 may be used with stiffener 2A 803.

The latest thermostat Part Nos. are as follows:-

13H 3727 (74oC,

16SoP ) , 13H 4070 (820C, 180o

P ) , 13H 4964 (88°C, 192oF)~

IMPORTANT: iUlllllll 01 tho Ir.inddescribed on tt>is~UI may be 6><cluo.d bv 1"'o.anTIS <lIth" ()wl\'" ".Ntr. ~ .•'_M .... 'k. _k....._._~_.._.

Issued b~: BRITISH LEYlAND SPECIAL TUNING

ABI NGOON - ON· THAM ES • BE RKSH IRE

SPECIAL ·TUNING DATA

DEPARTMENT

£NGlA~O

Mod.t GEnERAL Shut Z - 5 Issue t

-'

The follnilag ohart shows Piston DimensioDs for I A I Seri 6S engines.

Part No. lZA 187 12A US 12A 280 12A 120 l2A 673 120 303 ~2G ]C6l.2A ".C-.2A 946 \

Bore ~.470'· 2·478" 2.478" 2·47A" 2· 543" 2·~3" 2·~ .. 2· I"Pin Db. -0·625" 0.6~5" O. 625'~ O·&2S" 0·625" 0.625" 0.62 .. 0- ..ComDr.,non Ht. 1·339" 1· )]9" 1· 339" 10495" 1·]45" l·lM" lol'il ," 1. "Pilton H~Qht 2. 59~n 2·592" 2.592" 2·718" 2.288" 2·~ .. 1·61 ..Rinas .. 4 .. .. .. " .. 4Cra_ • Fl.t- '·2ee ;l.79<:c .S7cc 5.69cx; 6·9cI: 2·4kc 1U.16e<:

.010" +010" .010" tOl0" +010" .010" .010" ..010"O/S +020" +020" .020" .020" +020" -0020" -0020" .020"",v 11.11 ab1e -0030" +030" .030" +0)0"

+O~" ~" +CMQ" ..040"998 ADO Hi ADe 16

Std. use (bl 9CG 9C 9CO e..a Ilf-Mlni AIIt1I PGR 99BeeLie !'11n.1. Hom.t

__'.N"10980: c:oaa.r

Connecting 2A &54 2A 654 2A 6S4 ~ 654 120 12)-, 120 12)- 12G 12loo 120 12~

Rodl Cel 2A 656 2A 656 - 2A 656 ~ 656 120 126 120 126 120 126 120 126eonment (d) c. e c e lIP. Ff S4 rf F~ Pf

sa 24.32Part No. C-AL\. 639 C-At.o\ 637 C""IA&o\ 711 c...ua ~3 eo 2414 80 546 80 2545-Bore 2·538" -2.5lS" 2.667" 2·790" 2·78C" 2. " 2.780"Pin Db. 0.687" 0·687" 0·687" .81J" ·813" . .. .813"ColllDreaaion Ht .. 1.400" 1·600" 1·139" 1.495" 1·U5" 1. " 1."95"Pbton Hcdaht 2·15~" 2.152" 2.092" 2·110" 2.310" 2. " 2·'45"Rinal 3 4 3 -4 (e) 4 4. "Crown (al ).55cc. R 3.5cc R P"lat r18t '6.6 11·l)· 15.a

O/S Nil Nil Ntl .9ee (e).010 .010 +010-0020 .020 +020

Std use (b) f' ,. r 970cc '.9 '12cc 12cc

'.9' 1071/1275Connecting C-AE,A 620 c-m 620 c-m 706 12G 176 120 176 .ux; 520 AID 520Rods (c l c-m 621 C-.u:A 621 C-m 709 .CollWll~t Sd I se , I se 1 I Sd. I se, I 5l!. r

'al D. Dish, followed by approx. capacity of 4lahFlat - pistons ~ve flat top'R • Raised. followed by apprcx. cepac~ty of do~

(bl Engine Pr~fix or car type, ADO IS i. 1100/1300 rangeFJ is Formula Junior'S 1,s Cooper • S'12cc 11 !pr1te~dget

(~) Connecting rods ar~ handed, two off each required. One Psrt No. indicates fouriden ti cal rods.

\dl Sd means solid skirt, sp Ipllt ~.rt piston, Ff means fully floating ~d9eon pin.e lTIearlS C16mp _type gudgeoh pin. I means interference fj t. qudq~n pin requiringspecial \-001

(el BG 243? availablE' •. 010" & .020" e .....D:; 043 is only ..040"3 ring piston e-~EC 190 available Std size only12G l'h and ADG S20 are lnterchanqeable as sets, having Identlr~l dimenBions