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Jun 02, 2011 11:36 am
Jun 02, 2011 11:36 am
Subject: Re: Power At Last
Hi Chris,
Never too late for interesting comments and observations.
Very interesting to read your views.
I do notice Chris in your comments and I notice it a lot with customers I talk to, that when referring to "performance modifications" people tend to associate this with race engines and revy characteristics. Not necessarily so! These old engines ware designed for very poor fuels etc and mostly have very low compression ratios, terrible port shaping and combustion chamber shapes etc, it is a simple enough job to apply modern thinking, understanding and practices etc to achieve very good and useful power increases all through the rev range and many times improving low end drivability and torque even more than outright power. Of course you can also do it badly as it would seem someone did with your triple carb setup.
CR is also a massively misunderstood "word" that I often have to explain.
In short the only CR number you can easily calculate with any real accuracy is your "static compression ratio" (this is simply your engines volumes etc calculated) BUT this has little real relevance to actual "dynamic compression ratio"
eg. if we take a 2 litre Lagonda, this has some of the worst shaped ports imaginable, the flow is dreadful both in and out of the engine, so our "volumetric efficiency" (cylinder filling) is very poor. (let us say 50% at rpm "X") so it does not take a genius to deduct that this engine with a 6:1 static compression ratio will actually only be about 3:1 at rpm "X" simply because the engine can not fill it's cylinders!
Because the initial design is so bad, we can easily help it fill those cylinders with better porting and say a better camshaft profile we immediately increase the dynamic CR and thus help the entire performance curve and gain more torque and ultimate power.
I agree with you that the 16/80 is a pleasant engine, in standard good condition it makes for nice driving. The problems we encounter and the comments we get are Motorway driving when one does not want to sit with the trucks but wants to cruise in the middle lane at standard motorway speeds of today's traffic for any length of time, 70+ mph and also those who like to compete in rallies etc and need a car to pull up the mountains and hills with more ease.
I see Peter's point, but I don't see the difference between changing a piston that gives 6:1cr and changing a piston that gives 8:1cr! etc etc etc, Both are new and so Not Original, so if it does not change the external look of the engine and you can not tell it is in there other than the extra enjoyment and ability when driving, then why not! I am sure the components in Peter's own engine are not exactly as standard either, eg shell bearings to rods, more modern ignition coils etc! are these acceptable but other changes not? Do we revert to using the original pre-war spark plugs too?
Either ABSOLUTELY 100% original with absolutely NO deviation in any way shape or form what so ever. Including leaky oil seals! Surely part of a pre-war car ;o)
OR
Do as you like as long as you keep to "period" modifications.
I would prefer to see original engines and original cars "looking" as they left the factory, but I personally feel we should not be too pedantic!
Personal choices for personal vehicles that are used by different people for different uses.
Neither are wrong or right, and we should refrain from trying to impose our views on others, voice them by all means but not "impose". It is down to the individuals to "choose" that is our right! and let's face it. The more our cars get used and enjoyed the better our hobby will be!
As for value. Well Peter, your comments need clarifying here with a little "insider knowledge" In the context of engine power your comments are far from the reality! however, I agree that in general a more original car will be worth more than a highly modded one. But if the car looks great but goes very badly then you will struggle to sell it. "period". (unless it has something extra to offer in the way of super rarity etc) We can now get a very good premium for a 2 litre with one of our special engines fitted, as opposed to a standard 2 litre. They both look exactly the same so it's Simply because it is much more powerful and usable and "for most" more enjoyable. Same goes all the way through the range! and through many other makes and models right up to the top! Simple reason is that more people own the less rare and less expensive cars and can't afford the price of an 8c Alfa etc, they want the experience but without paying silly prices. (some want both) They want to do the classic events etc and want to have fun with their cars. They don't want to be the "slow car" or to spend every evening of the rally fiddling with their engines to try to make them work half reasonably so they can participate the next day! People want cars they can enjoy the pleasure of driving with, and in the majority of cases today this means having a reasonably powerful engine with fairly good reliability! They vote with their pockets and we see this on the showroom floor!
Again, Each to their own and I am not saying you are wrong Peter, just that we are all entitled to our own views! and we as a company are led by our customers / fellow enthusiasts, we do not create things that nobody wants, we do as we are asked! and when asked by enough people we undertake projects like this one.
Very best regards and secretly wishing we were not so busy so we could maybe get a bit further with this project!
Julian
Hi Chris,
Never too late for interesting comments and observations.
Very interesting to read your views.
I do notice Chris in your comments and I notice it a lot with customers I talk to, that when referring to "performance modifications" people tend to associate this with race engines and revy characteristics. Not necessarily so! These old engines ware designed for very poor fuels etc and mostly have very low compression ratios, terrible port shaping and combustion chamber shapes etc, it is a simple enough job to apply modern thinking, understanding and practices etc to achieve very good and useful power increases all through the rev range and many times improving low end drivability and torque even more than outright power. Of course you can also do it badly as it would seem someone did with your triple carb setup.
CR is also a massively misunderstood "word" that I often have to explain.
In short the only CR number you can easily calculate with any real accuracy is your "static compression ratio" (this is simply your engines volumes etc calculated) BUT this has little real relevance to actual "dynamic compression ratio"
eg. if we take a 2 litre Lagonda, this has some of the worst shaped ports imaginable, the flow is dreadful both in and out of the engine, so our "volumetric efficiency" (cylinder filling) is very poor. (let us say 50% at rpm "X") so it does not take a genius to deduct that this engine with a 6:1 static compression ratio will actually only be about 3:1 at rpm "X" simply because the engine can not fill it's cylinders!
Because the initial design is so bad, we can easily help it fill those cylinders with better porting and say a better camshaft profile we immediately increase the dynamic CR and thus help the entire performance curve and gain more torque and ultimate power.
I agree with you that the 16/80 is a pleasant engine, in standard good condition it makes for nice driving. The problems we encounter and the comments we get are Motorway driving when one does not want to sit with the trucks but wants to cruise in the middle lane at standard motorway speeds of today's traffic for any length of time, 70+ mph and also those who like to compete in rallies etc and need a car to pull up the mountains and hills with more ease.
I see Peter's point, but I don't see the difference between changing a piston that gives 6:1cr and changing a piston that gives 8:1cr! etc etc etc, Both are new and so Not Original, so if it does not change the external look of the engine and you can not tell it is in there other than the extra enjoyment and ability when driving, then why not! I am sure the components in Peter's own engine are not exactly as standard either, eg shell bearings to rods, more modern ignition coils etc! are these acceptable but other changes not? Do we revert to using the original pre-war spark plugs too?
Either ABSOLUTELY 100% original with absolutely NO deviation in any way shape or form what so ever. Including leaky oil seals! Surely part of a pre-war car ;o)
OR
Do as you like as long as you keep to "period" modifications.
I would prefer to see original engines and original cars "looking" as they left the factory, but I personally feel we should not be too pedantic!
Personal choices for personal vehicles that are used by different people for different uses.
Neither are wrong or right, and we should refrain from trying to impose our views on others, voice them by all means but not "impose". It is down to the individuals to "choose" that is our right! and let's face it. The more our cars get used and enjoyed the better our hobby will be!
As for value. Well Peter, your comments need clarifying here with a little "insider knowledge" In the context of engine power your comments are far from the reality! however, I agree that in general a more original car will be worth more than a highly modded one. But if the car looks great but goes very badly then you will struggle to sell it. "period". (unless it has something extra to offer in the way of super rarity etc) We can now get a very good premium for a 2 litre with one of our special engines fitted, as opposed to a standard 2 litre. They both look exactly the same so it's Simply because it is much more powerful and usable and "for most" more enjoyable. Same goes all the way through the range! and through many other makes and models right up to the top! Simple reason is that more people own the less rare and less expensive cars and can't afford the price of an 8c Alfa etc, they want the experience but without paying silly prices. (some want both) They want to do the classic events etc and want to have fun with their cars. They don't want to be the "slow car" or to spend every evening of the rally fiddling with their engines to try to make them work half reasonably so they can participate the next day! People want cars they can enjoy the pleasure of driving with, and in the majority of cases today this means having a reasonably powerful engine with fairly good reliability! They vote with their pockets and we see this on the showroom floor!
Again, Each to their own and I am not saying you are wrong Peter, just that we are all entitled to our own views! and we as a company are led by our customers / fellow enthusiasts, we do not create things that nobody wants, we do as we are asked! and when asked by enough people we undertake projects like this one.
Very best regards and secretly wishing we were not so busy so we could maybe get a bit further with this project!
Julian