The History of Austin-Healeys.com

Welcome to Austin-Healeys.com History Page

This is the 4th location of my website, but once I purchased this domain, I have had to move hosts

Over the years, the site began as a general interest webpage covering many topics, and has been refined to become the home of my car hobby.

Here are the address of the first three sites…

One is still active, but points to this one

- http://www.geocities.com/TheTropics/Shores/1256
(Started by May 1997 – left due to space restrictions)

- http://members.xoom.com/spridget
(Began in early 1998 until xoom was bought by NBCi and closed the account)

- http://carport.virtualave.net/
(left due to excessive pop-up’s by host)

First posting to the team.net mailing lists
- http://www.team.net/cgi-bin/wilma_hiliter/mgs/199705/msg01103.html

 

Austin Healey Sprite – M. G. Midget “A”-SERIES ENGINE DETAILS

Austin Healey Sprite – M. G. Midget

“A”-SERIES ENGINE DETAILS

Dimensions are in inches unless otherwise stated.

(information from SPRITE, MIDGET, 1958-71 AUTOBOOK, by Kenneth Ball, Autopress Ltd. 1971)

Bore and Stroke (mm):
  948 cc 62.94 X 76.20
  1098 cc 64.58 X 83.72
  1275 cc 70.61 X 81.28
Compression ratio (low):
  948 cc (‘Sprite’ I and II, ‘Midget’ I) 8.3:1
  1098 cc (‘Sprite’ II and III, ‘Midget’ I and II) 8.1:1
  1275 cc (‘Sprite’ IV, ‘Midget’ III) 8.0:1
Compression ratio (high):
  948 cc (‘Sprite’ I and II, ‘Midget’ I) 9.0:1
  1098 cc (‘Sprite’ II and III, ‘Midget’ I and II) 8.9:1
  1275 cc (‘Sprite’ IV, ‘Midget’ III) 8.8:1
Firing Order 1-3-4-2
Main bearings, journal diameter:
  All capacities except ‘Sprite III and IV, ‘Midget’ II and III 1.7505-1.7510
  1098 cc and 1275 cc (‘Sprite’ III and IV, ‘Midget’ II and III) 2.0005-2.0010
Main bearing liners, running clearance
  948 cc (‘Sprites’ and ‘Midgets’) .001 to .0025
  1098 cc (‘Sprites’ and ‘Midgets’) .001 to .0025
  1275 cc (‘Sprite’ IV, ‘Midget’ III) .001 to .0027
Main Bearings, lining material
  ‘Sprite’ I Whitemetal
  948 cc (‘Sprite’ II and ‘Midget’ I) Lead/indium
  1098 cc (‘Sprites’ and ‘Midgets’) Lead/indium
  1275 cc (‘Sprite’ IV, ‘Midget’ III) VP3 lead/indium or nfm/3B
Crankshaft regrind undersizes
  948 cc and 1098 cc -.010, -.020, -.030, -.040
  1275 cc No more than >010 without heat treatment
Crankshaft end float (all Capacities) .002 to .003
Crankpin diameter (all capacities) 1.6254 to 1.6259
Connecting rod centers (all capacities) 5.75
Big-end bearings, running clearance (all capacities) .001 to .0025
Big-end bearings, lining material Copper/lead
  948 cc (‘Sprite’ II and ‘Midget’ I) Lead/indium
  1098 cc and 1275 cc (‘Sprites’ and ‘Midgets’) Lead/indium
Connecting rod end float on crankpin (all capacities) .008 to .012
Clamped gudgeon pin:
  Diameter .6244 to .6246
  Clearance in piston .0001 to .0003
Fully floating gudgeon pin (fit in piston -1098cc) Hand push
Gudgeon Pin (1275 cc)
  Fit in small end (interference) Pressed in small-end, .0008 to .0015
  Fit in piston Hand push
Piston Type Aluminum alloy
Standard piston, suitable bore size:
  948 cc 2.4778 to 2.4781
  1098 cc 2.5424 to 2.5447
  1275 cc 2.7803 to 2.7800
Piston oversizes:
  948 cc +.010, +.020, +.030, +.040
  1098 cc and 1275 cc +.010 and +.020
Piston clearance, bottom of skirt:
  948 cc (‘Sprite’ I) .0010 to .0016
  949 cc (‘Sprite’ II, ‘Midget’ I ) .0016 to .0022
  1098 cc .0005 to .0011
  1275 cc .0015 to .0021
Piston clearance, top of skirt:
  949 cc (‘Sprite’ II, ‘Midget’ I ) .0036 to .0042
  1098 cc .0021 to .0037
  1275 cc .0029 to .0037
Piston rings, compression:
  Top Plain
  Second Taper
  Third Taper
Fourth piston ring, all capacities except 1275 cc and later 1098cc Slotted scraper
  1275 cc and later 1098 cc Duraflex 61
Width of compression rings:
  948 cc .0690 to .0700
  1098 cc (top ring) .0620 to .0625
  1098 cc (second and third rings), 1275 cc (all three) .0615 to .0625
Width of slotted scraper ring:
  All capacities except 1275 cc and later 1098 cc .124 to .125
Ring gap, fitted, all capacities except 1275 cc .007 to .012
  1275 cc (top ring) .011 to .016
  1275 cc (second and third rings) .008 to .013
  Duraflex 61 (rails and side spring) .012 to .028
Ring clearance in groove
  948 cc, 1275 cc (top, second and third) .0015 to .0035
  1098 cc .0020 to .0040
Camshaft journal diameters:
  Front 1.6655 to 1.666
  Center 1.62275 to 1.62325
  Rear 1.3725 to 1.3735
Camshaft bearings:
  Front Steel-backed whitemetal
  Center and rear (‘Sprite’ I) Direct in crankcase
  (All ‘Sprites’ and ‘Midgets’, except ‘Sprite’ I, have three whitemetalled bearing liners)
Camshaft clearance:
  Front bearing (also center and rear when linered) .001 to .002
  Center and rear bearings .00125 to .00275
Camshaft end float .003 to .007
Timing chain Single roller (Duplex on 1275 cc)
timing chain, pitch .375
Timing chain, length 52 pitches
Valve seat angle 45 deg.
Valve lift:
  948 cc (‘Sprite’ I) .285
  949 cc (‘Sprite’ II, ‘Midget’ I ) .312
  1098 cc .312
  1275 cc .318
Valve head diameter, inlet:
  948 cc (‘Sprite’ I) 1.0937
  949 cc (‘Sprite’ II, ‘Midget’ I ) 1.151 to 1.156
  1098 cc 1.151 to 1.157
  1275 cc 1.307 to 1.312
Valve head diameter, exhaust
  948 cc (‘Sprites’ and ‘Midgets’) 1.00 to 1.005
  1098 cc 1.00 to 1.005
  1275 cc 1.1515 to 1.1565
Valve stem diameter, inlet:
  948 cc (‘Sprites’ and ‘Midgets’) .2793 to .2798
  1098 cc and 1275 cc .2793 to .2798
Valve stem diameter, exhaust (all capaciteis) .2788 to .2793
Valve stem clearence, inlet (all capacities) .0115 to .0025
Valve stem clearance, exhaust:
  948 cc and 1098 cc .0020 to .0030
  1275 cc .0015 to .0025
Valve rocker clearance (cold):
  All capacities 0.012
  Competition work 0.015
For checking timing only:
  948 cc (‘Sprite’ I) 0.019
  949 cc (‘Sprite’ II, ‘Midget’ I ) 0.021
  1098 cc 0.021
  1275 cc 0.029
Valve springs —free length
  948 cc (‘Sprite’ I) 1.750
  948 cc (‘Sprite’ II, ‘Midget’ I ), inner 1.672
  950 cc (‘Sprite’ II, ‘Midget’ I ), outer 1.750
  1098 cc (‘Sprites’ and ‘Midgets’), inner 1.672
  1098 cc (‘Sprites’ and ‘Midgets’), outer 1.750
  1275 cc (‘Sprite’ IV, ‘Midget’ III), inner 1.703
  1275 cc (‘Sprite’ IV, ‘Midget’ III), outer 1.828
Valve spring pressure (valve closed):
  948 cc (‘Sprite’ I) 52.5 lb
  948 cc (‘Sprite’ II, ‘Midget’ I ), inner 18 lb
  950 cc (‘Sprite’ II, ‘Midget’ I ), outer 52 lb
  1098 cc (‘Sprites’ and ‘Midgets’), inner 18 lb
  1098 cc (‘Sprites’ and ‘Midgets’), outer 52 lb
  1275 cc (‘Sprite’ IV, ‘Midget’ III), inner 25 lb
  1275 cc (‘Sprite’ IV, ‘Midget’ III), outer 51 lb
 
Valve timing (‘Sprite’ I):
  Inlet opens 5 deg. Before TDC
  Inlet closes 45 deg. After BDC
  Exhaust opens 40 deg. Before BDC
  Exhaust closes 10 deg. After TDC
  With rocker clearance of .019, for checking only
Valve timing (948 cc ‘Sprite’ II and ‘Midget’ I. All 1098 cc and 1275 cc):
  Inlet opens 5 deg. Before TDC
  Inlet closes 45 deg. After BDC
  Exhaust opens 51 deg. Before BDC
  Exhaust closes 21 deg. After TDC
  With rocker clearance of .021, for checking only (.029 for 1275 cc)
Oil sump capacity including filter (pints) — all capacities 6 1/2
 
Oil pressure relief valve springs, free length:
  ‘Sprite’ I 2 7/8
  Later ‘Sprites’ and ‘Midgets’ 2.86
 
Oil pressure (normal running), lb/sq in:
  All except ‘Sprite’ IV and ‘Midget’ III 60
  ‘Sprite’ IV and ‘Midget’ III 40 to 70
 
Exhaust emission control
  Exaust gas analyser reading:
  At engine idling speed 2 to 2.5% CO (provisional)
  Air pump test speed 1200 rev/min (engine)

Austin Healey Sprite – M. G. Midget SU CARBURETOR DETAILS

Austin Healey Sprite – M. G. Midget

SU CARBURETOR DETAILS

Dimensions are in inches unless otherwise stated.

(information from SPRITE, MIDGET, 1958-71 AUTOBOOK, by Kenneth Ball, Autopress Ltd. 1971)

Type (Sprite I) SU H.1 (two)
Needle (normal) GG
Type (Sprite II and Midget I, 948 cc) SU H.S.2 (two)
Needle (Standard) V3
Needle (Rich) V2
Needle (Weak) GX
Spring Light Blue
Type (1098 cc Sprite II and Midget I) SU H.S.2 (two)
Needle (Standard) GY
Needle (Rich) GG
Needle (Weak) M
Spring Blue
Type (1098 cc Sprite III, Midget II, 1275 cc Sprite IV, Midget III SU H.S.2 (two)
Needle (Standard) AN
Needle (Rich) H6
Needle (Weak) GG
Spring blue
Spring (Sprite IV and Midget III) Light Blue
Fuel pump (all models except Sprite III and IV and Midget II and III) AC ‘Y’ type (mechanical)
Sprite III and IV, Midget II and III SU type A.U.F. (Electric)
Type (1275 cc Sprite IV, Midget III) Exhaust emission control SU H.S.2 (two)
Specification: Exhaust emission control:  
  Fixed needle type AUD 266
  Spring-loaded type AUD 328
Needle, fixed type, exhaust emission control AN
  Spring-loadaed type, exhaust emission control AAC
Piston spring, exhaust emission control Blue
Initial jet adjustment, exhausted emission control 11 flats from bridge
Idling speed, exhaust emission 1000 rev/min
Fast-idle speed, exhaust emission 1100 to 1200 rev/min