Post by 33grinder on Oct 11, 2009 13:38:14 GMT
Well, Rover's tune-up day came yesterday. I took her to my mate's MOT station after he had finished the last MOT. The gas analyser was put up her exhaust pipe and the timing gun set up.
As suspected, the timing was quite far out, we ended up setting her to 7 degrees BTDC. COs was measuring about 6 or 7%, which is a little high for MOT purposes but she seemed to run better at this level.
Further tuning of the Holley continued and my friend found that each front barrel could be independently set and one side was running lean. This was all adjusted.
Well, the difference was startling to say the least! There is a very slight cough when the accellerator is floored, and there was much head scraching and adjusting of the dwell angle to try to find the sweet spot.
In the end we couldn't totally erradicate it and from further research I believe that due to the age of the engine there has been some stretch in the timing chain which prevents timing from being set accurately. I was planning at some stage to fit a piper cam so when the time comes I will fit a duplex timing chain at the same time which should resolve that.
Friends' comments so far range from 'bloomin' Hell!' to 'I think you should upgrade your brakes!', so that bodes well. ;D
Now my mechanic friend has returned from Malta I have broken the bad news about the leaking core plug(s) and that it will be a gearbox out job but he seems unphased by that which is good. Ho-hum, onwards and upwards!
As suspected, the timing was quite far out, we ended up setting her to 7 degrees BTDC. COs was measuring about 6 or 7%, which is a little high for MOT purposes but she seemed to run better at this level.
Further tuning of the Holley continued and my friend found that each front barrel could be independently set and one side was running lean. This was all adjusted.
Well, the difference was startling to say the least! There is a very slight cough when the accellerator is floored, and there was much head scraching and adjusting of the dwell angle to try to find the sweet spot.
In the end we couldn't totally erradicate it and from further research I believe that due to the age of the engine there has been some stretch in the timing chain which prevents timing from being set accurately. I was planning at some stage to fit a piper cam so when the time comes I will fit a duplex timing chain at the same time which should resolve that.
Friends' comments so far range from 'bloomin' Hell!' to 'I think you should upgrade your brakes!', so that bodes well. ;D
Now my mechanic friend has returned from Malta I have broken the bad news about the leaking core plug(s) and that it will be a gearbox out job but he seems unphased by that which is good. Ho-hum, onwards and upwards!