Just out of couriosity, I’ve been keeping a list of cam data for the Murena 2.2 engine. Recently I discussed with Youri from this forum that it would be a good idea to share them here. I’ll be updating this list if I receive corrections or details on performance or engine configurations, so please send it to me. Please feel free to use the thread to discuss and share stories about the cams and engine configurations.
| Type | Lift
(mm) | Timing | LCA
inlet
exhaust | Periods
inlet
exhaust | Overlap | Timing lift | Clearance
inlet
exhaust
(mm) | Engine configuration |
| Stock | 6.5 | 19°12'/56°48'
54°48'/13°12' | 108°68'
110°68' | 256°
248° | 32°24' | TBD | 0.2
0.3 | Bosch distributor and single Solex carburettor. |
|
| K142 | 7.4 | 27°/72°
69°30'/29°30' | 112°50'
110° | 279°
279° | 56°30' | TBD | 0.2
0.3 | Murena S, twin Solex ADDHE 40, Ducellier distributor, stock cylinder head. |
|
| Politecnic Maxiroute | 7.75 | 30°/86°
78°/42° | 118°
108° | 296°
300° | 72° | TBD | TBD | TBD |
|
| Holbay Tornado 58C | 7.06 | 39°/77°
79°/37° | 109°
111° | 296°
296° | 76° | TBD | 0.25
0.3 | Fastroad cam with stock head, carburettor, and distributor |
|
| Danielson K230 | 7.45 | 21°/77°
85°/24° | 118°
120°50' | 278°
289° | 45° | TBD | TBD | Turbo |
|
| JRD No 1 | 7.0 | 34°/71°
68°/32° | 106° | 285°
280° | 66° | 0.5 | 0.25
0.30 | Designed for a racing class defined by Simca with Chrysler 2L engine and Lola or Chevron chassis |
|
| JRD No 10 | TBD | 31°/62°
58°/35° | 105.5°
101.5° | 273°
273° | 66° | 0.5 | TBD | For rally |
|
| Condrillier | 7.5 | 35°/85°
85°/35° | 115° | 300°
300° | 70° | TBD | TBD | Designed by Condrillier as a fast road camshaft |
| Piper 3777 | 8.3 | TBD | TBD | TBD | TBD | TBD | TBD | TBD |
Notes:Lift is measured on the cam. Rocker arms multiply this by a ratio and the clearance is subtracted from that number to get the lift the engine sees at the valves.
Timing lift is the lift (on cam) by which the periods are measured.
Unless there’s an adjustable cam sprocket installed in the engine, cam timing is fixed.
Timing angles are specified as: Inlet opening BTDC; inlet closing ATDC; exhaust opening BBDC; exhaust closing ABDC.
Some definitions:LCA: Lobe Centreline Angle
TDC: Top Dead Center, piston at the highest point
BDC: Bottom Center, piston at lowest point
BTDC: Before Top Center, i.e. while piston rising
ATDC: After Top Center, i.e. while piston lowering
BBDC: Before Bottom Center, i.e while piston lowering
ABDC: After Bottom Center, i.e. while piston risinng
Acknowledgements:Thanks to Youri Nieuwenhuizen for actually measuring and verifying the data on the K142, Danielson, JRD and Condrillier cams, and for calculating LCA's
Thanks to Roy Gillard for supplying me my original data on Holbay, K142 and Stock cams
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