| Maker | ABC Co | Armstrong-Siddeley Tiger IX | Armstrong-Siddeley Tiger VI | Armstrong-Siddeley Cheetah IX | Armstrong-Siddeley Cheetah X | Armstrong-Siddeley Cheetah VA | Bristol Mercury VIII |
| Arrangement | Horizontal | Radial | Radial | Radial | Radial | Radial | Radial |
| Cooling | Air | Air | Air | Air | Air | Air | Air |
| No of Cyls | 4 | 14 | 14 | 7 | 7 | 7 | 9 |
| Bore/Stroke | 4.2" x 4.8" | 5.5" x 6.0" | 5.5" x 6.0" | 5.25" x 5.25" | 5.25" x 5.5" | 5.25" x 5.5" | 5.75" x 6.5" |
| Displacement | 244 cu ins | 1996 cu ins | 1996 cu ins | 834 cu ins | 834 cu ins | 834 cu ins | 1519 cu ins |
| Comp Ratio | 5.6:1 | 6.2:1 | 6.2:1 | 6.35:1 | 6.35:1 | 5.2:1 | NA |
| bmep Cruise | 130 | 104 | 104 | 104 | 106 | 102 | 159 |
| Blower ratio | N/A | 5.4:1 | 5.4:1 | 5.4:1 | 6.52:1 | 1:1 | NA |
| Cyl Material | CI/Steel | Steel | Steel | Steel | Steel | Steel | Steel |
| Valves per cyl | 1 Inl 1 Exh | 1 Inl 1 Exh | 1 Inl 1 Exh | 1 Inl 1 Exh | 1 Inl 1 Exh | 1 Inl 1 Exh | 1 Inl 1 Exh |
| Valve Arr. | OHC | OHV | OHV | OHV | OHV | OHV | OHV |
| HP max - not Take-Off | NA | 804 | 810 | 345 | 350 | 326 | 840 |
| @ RPM | NA | 2450 | 2450 | 2425 | 2425 | 2400 | 2750 |
| @ Altitude | Sea Level | 7200ft | 6400ft | 7800ft | 7300 ft | Sea Level | 14000 |
| HP Take-Off | NA | 880 | 840 | 368 | 340 | 296 | 730 |
| @ RPM | NA | 2375 | 2150 | 2300 | 2100 | 2100 | 2650 |
| HP Cruise | 75 | 560 | 560 | 230 | 235 | 225 | NA |
| @ RPM | 1875 | 2150 | 2150 | 2100 | 2100 | 2100 | NA |
| Fuel Octane | NA | 87 | 87 | 87 | 87 | 87 | NA |
| Prop Drive | Direct | Geared | Geared | Direct | Direct | Direct | Geared |
| Dry Weight | 219 lbs | 1220 lbs | 1180 lbs | 635 lbs | 635 lbs | 596 lbs | 980 lbs |
| lb/Cruise HP | 2.92 | 2.18 | 2.11 | 2.76 | 2.70 | 2.65 | 1.17 |
| Carb(s) | 1x Claudel-Hobson | 1x Claudel-Hobson | 1x Claudel-Hobson | 1x Claudel-Hobson | 1x Claudel-Hobson | 1x Claudel-Hobson | NA |
| Ignition | BT-H Mag(2) | BT-H Mag(2) | BT-H Mag(2) | BT-H Mag(2) | BT-H Mag(2) | BT-H Mag(2) | NA Mag(2) |
| Electric Starter | N/A | Hand/Electric | Hand/Electric | Hand/Electric | Hand/Electric | Hand/Electric | NA |
| Length | 25.50" | 68.30" | 65.00" | 46.75" | 52.90" | 48.70" | NA |
| Height/O.D. | 28" | 50.80" | 50.80" | 47.70" | 47.70" | 47.70" | 51.50" |
| Width | 39" | 33.27" | 33.80" | 21.55" | 22.22" | 21.85" | NA |
| Ht above bed | NA | NA | NA | NA | NA | NA | NA |
| Mount Dia | NA | NA | NA | NA | NA | NA | NA |
Let me know if any of the above does not read true, or if you have information that does not agree. Wherever possible, I will update these pages on a regular basis as data comes in.