51fixer wrote:
Lynn Allen wrote:
Rich, can you change out the nose cases of the Mk engines from the contra to single blade like you can for the 3350 slow noses, etc or do you have to have a select Mk for the single 5 blade?
Thanks
The 58 is derived from the 57 and there is also a design called the 5900 which was a single prop shaft while the 57 and 58 were the contra prop setups. These all were based on the same design and layout with the prop shaft set up being the only variation. The 5900 didn't seem to make it to production. I suspect it was a commercial offering in a RR power plant design, think Shackelton engine, nacelle and radiator set up but with a single prop shaft and maybe 4 of them on an airliner.
The 60 series of the Griffon along with the Mk 74 are also a family series with different nosecase gearing, slight differences in the supercharger and your choice of Bendix carb or British Injection Fuel system. These all had a single prop shaft, intercooler and the same crankcase and nosecase housing.
Some differences that come to mind-
65 has 510 nosecase gears (turns faster and sports the smaller 5 blade prop), Bendix carb and runs at 18 lbs boost with 2030 hp.
66 is the same but has an extra gear in the nosecase to run a blower to pressurize the cockpit of the high altitude PR XIX.
67 has some alterations in the carb and cams to run 25 lbs of boost and get around 2350 hp.
74 has 471 nosecase gears (slower turning and runs a larger 4 blade prop), British injection carb and fuel pump, different cam.
To run a 60 series nosecase on a 58 takes a bit of doing as they have a different size outline. The gear set up and mounting location for the cabin blower on the PR XIX is present on all the 60 series and 74 crankcases and nosecases. It just isn't installed.
On the 58 there isn't any provision and the casting doesn't have the material for it. The 58 also has internal oil galleys for some of the oil feeds that are external lines on the 60 series. To bolt up a 60 series nosecase to a 58 will take some doing in the engineering and fabrication dept.
Looked in the AP2234K&L Volume I manual and the genealogy goes-
Griffon 61
Prop Gearing .451 to 1
2 speed, 2 stage blower with 5.84 and 7.58 to 1 ratios
Boost 18 psi
Bendix 9.T.40/1 Carb
This splits in 2 groups-
Group 1-
Griffon 65 is the same as above with Prop Gearing being .51 to 1
Griffon 66 is the same as a 65 with the addition of the cabin blower drive.
Group 2-
Griffon 64 is the same as a 61 but has a modified Boost Regulator, Ignition Timing Device, Ignition Timing Controls, Increased Capacity Oil Pump and a different CSU or Prop Gov.
This allows 25 psi boost (80+ inches of manifold Pressure)
Griffon 67 is the same as a 64 but with .51 to 1 Prop Gearing
Griffon 69 is the same as a 64 but has modified rear feet mounting for booms with extra flexibility.
The 74 has .451 to 1 Prop Gearing
Supercharger gears of 5.167 and 6.79 to 1, different cam, and the RR Mk2 Series C Fuel Injection Carburation along with matching Automatic Boost Controller.