That's not the engine we were talking about. It's another! This one has plain big ends , look at the external oil pump arrangements. Or should that be derangements?
ET: Engine (Twin) Camshaft design
- Thread starter roger edwards
- Start date
It's one thing to modify something to go better, but it's another to keep it looking original as well. As much as I admire the work gone into that outfit,it certainly looks off the mark.
D
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Roy
sorry but I've posted an incorrect photo, and don't have a correct one to hand.
If you have an appropriate photo perhaps you would oblige and set me right.
sorry but I've posted an incorrect photo, and don't have a correct one to hand.
If you have an appropriate photo perhaps you would oblige and set me right.
Thank you. Interesting to see how much effort has been put in to getting more oil round the engine. I have seen the same type of rotary pump used between the ignition system and the back of the timing cover. That is the 'magneto' was driven through the oil pump.
D
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David
cams were specials by Phil Joy
cams were specials by Phil Joy
D
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Phil
to copy the profile of the BSA cam 65-2442 into a format for a Vincent, see the attached file. It may be opened as a comma delimited file in Excel. Note the follower type is a radius pad finger.
This kind of exercise is fairly straightforward provided the complete engine's valve train geometry details are available.
No doubt this has been done before by someone, it's too obvious not to have been.
to copy the profile of the BSA cam 65-2442 into a format for a Vincent, see the attached file. It may be opened as a comma delimited file in Excel. Note the follower type is a radius pad finger.
This kind of exercise is fairly straightforward provided the complete engine's valve train geometry details are available.
No doubt this has been done before by someone, it's too obvious not to have been.
"No doubt this has been done before by someone, it's too obvious not to have been." - exactly my thoughts when asking my question, an obvious (post MK2) first stage for development.
I would assume that the late great Ian Hamilton must have done something similar in his cam development journey, as he was just so meticulous developing his engines, using the dyno to validate each change - that is how he obtained his '105' cam.
Thanks Grey One for the info, are you aware there are some mantissa number errors and column ommissions within the number stacks?
From what I have been told the Mallows engine originally used cam events derived from Honda F1 engine tech, apparently the original cams were not included in the sale, so that info cannot be validated - did you do the cam work for his engine then?.
I would assume that the late great Ian Hamilton must have done something similar in his cam development journey, as he was just so meticulous developing his engines, using the dyno to validate each change - that is how he obtained his '105' cam.
Thanks Grey One for the info, are you aware there are some mantissa number errors and column ommissions within the number stacks?
From what I have been told the Mallows engine originally used cam events derived from Honda F1 engine tech, apparently the original cams were not included in the sale, so that info cannot be validated - did you do the cam work for his engine then?.
D
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Phil, the cams are nothing to do with me, I simply measured them for record purposes when the engine was undergoing a general service. As I mentioned earlier, Phil Joy was said to have ground the profiles, but to what original or master I have no idea, and Phil when I asked him, could not recall where the original cams came from.
The data in the file, as far as I can ascertain, is all in order, but here I stand to be corrected because the original file format was not acceptable as an attachment, so I had to save it from Excel in a different format with the warning message that some of the data could be compromised. If you have come across any particular fault I would appreciate having the details to investigate.
The BSA cams that were copied by PEI for the Repco Brabham engine are not to my knowledge specified as to which cams in particular, but the regular fitment to the Gold Star engines were 65-1891 for exhaust, and 65-2442 for the intake. so without knowledge to the contrary, I'm assuming these profiles were the ones used.
Having the BSA cams for the Repco Brabham project, it seems a little surprising that PEI didn't at some stage consider using the same profiles for his Vincents, and I can only assume he had some good reason for not so doing - or perhaps he did, does anyone know ?
The data in the file, as far as I can ascertain, is all in order, but here I stand to be corrected because the original file format was not acceptable as an attachment, so I had to save it from Excel in a different format with the warning message that some of the data could be compromised. If you have come across any particular fault I would appreciate having the details to investigate.
The BSA cams that were copied by PEI for the Repco Brabham engine are not to my knowledge specified as to which cams in particular, but the regular fitment to the Gold Star engines were 65-1891 for exhaust, and 65-2442 for the intake. so without knowledge to the contrary, I'm assuming these profiles were the ones used.
Having the BSA cams for the Repco Brabham project, it seems a little surprising that PEI didn't at some stage consider using the same profiles for his Vincents, and I can only assume he had some good reason for not so doing - or perhaps he did, does anyone know ?
,I know nothing of the inside of Gold Stars but if they do not have lever cam followers then it would be a time consuming task, without the advantage of a computer, to convert their lift profiles so that they gave the same curve in a Vin. I do know of one tuner/builder who copied G50 cam lift onto a Vincent engine and that bike goes very well. However, the chap in question keeps things to himself and I have no idea how the conversion of an OHC cam works with a pushrod engine.
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