Tiff Needell's 1980 Rover V8 S SD1 Group 2 on our rollers
Discussion
Who said all publicity is good publicity Martin?
The wheel power was 322 and coastdown losses 28 giving our guesstimate of 350 at engine. Close to JE 350? I had been told it had seen 377 on JE dyno but that may have been incorrect. Like you I just enjoy driving things and listening to things. I have never claimed our figures are Gospel, neither do I care as long as figures are repeatable I can then say they are comparable with other cars on my rollers. Yours is a flying machine, better than the flat plane ex Tony Pond TR8 we tested years ago! I posted the car details as I thought it nice to show folk a lovely car that had been awol for a while, there cannot be many MK1 SD1s left at all, let alone character cars like yours! I know it pales into insignificance compared to some of your stable such as Porsche 862 Le Mans car or your (James Bond's original car?) blown 4 1/2 Bentley but it has a place in my heart for what it is, a much respected SD1![smile](/inc/images/smile.gif)
Peter
The wheel power was 322 and coastdown losses 28 giving our guesstimate of 350 at engine. Close to JE 350? I had been told it had seen 377 on JE dyno but that may have been incorrect. Like you I just enjoy driving things and listening to things. I have never claimed our figures are Gospel, neither do I care as long as figures are repeatable I can then say they are comparable with other cars on my rollers. Yours is a flying machine, better than the flat plane ex Tony Pond TR8 we tested years ago! I posted the car details as I thought it nice to show folk a lovely car that had been awol for a while, there cannot be many MK1 SD1s left at all, let alone character cars like yours! I know it pales into insignificance compared to some of your stable such as Porsche 862 Le Mans car or your (James Bond's original car?) blown 4 1/2 Bentley but it has a place in my heart for what it is, a much respected SD1
![smile](/inc/images/smile.gif)
Peter
That is interesting about timing advance, as you probably know many folk think the more the advance the more the power!
I assume you write from theory rather than hard practice as we regularly find we run low 20s in our best 2v engines. Best A series 1380 two engines at 21 degrees, 1500 Spitfire/Midget based engines 22 degrees max advance. TR6 6 cylinder, best engine 22 degrees. Best 1840 B series 24 degrees, however run the same B with a milder cam more suited to 1840 than 1950 and advance needed was 25.5 degrees even though it made a wider spread of torque and power with the same peak toque and power. Standard race MGB engines with loosening restrictions over the years to make racing more interesting for spectators by increasing power have changed from 34 degrees max with 92 at the wheels winning in 1987 to 27 degrees and 120 at the wheels winning in 2016. These were all on Shell best pump fuel and booster.
The above engiines have smaller to larger combustion chambers in the order written.
Peter
I assume you write from theory rather than hard practice as we regularly find we run low 20s in our best 2v engines. Best A series 1380 two engines at 21 degrees, 1500 Spitfire/Midget based engines 22 degrees max advance. TR6 6 cylinder, best engine 22 degrees. Best 1840 B series 24 degrees, however run the same B with a milder cam more suited to 1840 than 1950 and advance needed was 25.5 degrees even though it made a wider spread of torque and power with the same peak toque and power. Standard race MGB engines with loosening restrictions over the years to make racing more interesting for spectators by increasing power have changed from 34 degrees max with 92 at the wheels winning in 1987 to 27 degrees and 120 at the wheels winning in 2016. These were all on Shell best pump fuel and booster.
The above engiines have smaller to larger combustion chambers in the order written.
Peter
Years ago we had a bad dude cam (as The Donald would say). It was a design needing wider diameter followers than our standard B ones and the edge of the follower dug into the cam just each side of the nose
. We could have put an MGC follower in but we decided to junk the cam as only fast road spec. Talking to the late Bill Nicholson, at a tuning seminar where I was answering questions etc, he said there was a work around which was simplicity itself. Tuftride the cam lobes and followers and it can't dig in, he said this worked to perfection when he was working at BSA. Bill used Jack French cams....another blast from the past! It just reminded me about friction on followers and made me wonder if the tuftriding would reduce frictional losses twixt cam and followers?
Peter
![frown](/inc/images/frown.gif)
Peter
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