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  1. #1
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    Default Williams Helical Camshaft for SR type engines.

    I originally posted this in the "All Motor" section but possibly "VVL" is a more appropriate area.

    The end of the road for VVL?

    This post refers to the Helical Camshaft system - described below:

    Introduction

    Helical camshaft - Wikipedia, the free encyclopedia

    I would be interested to read peoples' opinions about this camshaft system.

  2. #2
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    Default Williams Helical Camshaft.

    Possibly people with SR engines may be interested in the following:

    Introduction
    Helical camshaft - Wikipedia, the free encyclopedia

    You can see from the general layout of the Suzuki GSX 250 helical cam prototype in the photos and videos that the SR-type valve gear is very similar in arrangement. This would imply that it may be possible to actually build a "bolt-in" variable camshaft for an SR engine.
    When the original HC prototypes were made and tested the people behind the HC project were totally unaware of the type of valve gear on SR engines - otherwise the prototype would have most likely been an SR of some kind.
    Since becoming aware of SR's the HC builders are contemplating bulding variable cams for this type of engine and would like to know if there would be much interest in these cams amonst SR owners.

    To complicate things - there are actually two types of variable cam - the simpler one (called the Type 1) has a continuous duration range from standard to about 40 crankshaft degrees above this. This is the type of cam shown running in the Daihatsu Charade engine on the HC website. It would probably not be particularly difficult to build this type of cam for an SR along with a similar centrifugal controller to that shown in the video (athough, obviously the SR would require two of these arrangements).

    Slightly more tricky would be to build a HC (or Type 2) cam for an SR. This typically would give a duration range of 85 to 100 degrees above standard (the prototype Suzuki is 85 degrees) basically this is enough duration to allow whatever RPM the SR bottom end could stand while retaining the standard idle speed etc.

    Anyhow the builders of these cams would like to hear peoples' opinions on these cams and whether there would be enough interest to justify building some SR prototypes.

    I attempted to post a similar thread to this a few days ago but (for whatever reason) it never appeared - I hope the other thread doesn't suddenly pop up as well as this one.

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    It looks like the earlier attempt at posting a new thread did suddenly "pop up" - sorry about that.

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    Quote Originally Posted by Sheepdog View Post
    Possibly people with SR engines may be interested in the following:

    Introduction
    Helical camshaft - Wikipedia, the free encyclopedia

    You can see from the general layout of the Suzuki GSX 250 helical cam prototype in the photos and videos that the SR-type valve gear is very similar in arrangement. This would imply that it may be possible to actually build a "bolt-in" variable camshaft for an SR engine.
    When the original HC prototypes were made and tested the people behind the HC project were totally unaware of the type of valve gear on SR engines - otherwise the prototype would have most likely been an SR of some kind.
    Since becoming aware of SR's the HC builders are contemplating bulding variable cams for this type of engine and would like to know if there would be much interest in these cams amonst SR owners.

    To complicate things - there are actually two types of variable cam - the simpler one (called the Type 1) has a continuous duration range from standard to about 40 crankshaft degrees above this. This is the type of cam shown running in the Daihatsu Charade engine on the HC website. It would probably not be particularly difficult to build this type of cam for an SR along with a similar centrifugal controller to that shown in the video (athough, obviously the SR would require two of these arrangements).

    Slightly more tricky would be to build a HC (or Type 2) cam for an SR. This typically would give a duration range of 85 to 100 degrees above standard (the prototype Suzuki is 85 degrees) basically this is enough duration to allow whatever RPM the SR bottom end could stand while retaining the standard idle speed etc.

    Anyhow the builders of these cams would like to hear peoples' opinions on these cams and whether there would be enough interest to justify building some SR prototypes.

    I attempted to post a similar thread to this a few days ago but (for whatever reason) it never appeared - I hope the other thread doesn't suddenly pop up as well as this one.
    When this guy did the original helical camshaft about 8 or 9 years ago, I was very interested to get something going for the SR engines and contacted him.
    He was on that stage more interested in getting it patented and trying to sell the idea to major car manufacturers.
    He had a feature of it in an Australian car magazine and I fell in love with the idea. Unfortunately the magazine didn't do any follow ups and it sort of died.
    As I am not going to do any more development in the SR's and are busy selling everything I have, I dont have a direct interest but would love to see someone doing it.
    As I could not get in contact with this guy in years, I have approach someone else with all the drawings and they were very impressed with it but funding something like that was out of my reach and put it on the backburner.
    One of the major features I liked is that with the right setup you could do away with your throttle plates, have any duration you like.
    Biggest drawback would have been to design a controller for it and a Ecu that could handle it, but would be doable.
    Last edited by kiwi-japie; 03-08-11 at 12:34 AM.

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    Kiwi - I am afraid that (after much head-scratching) I have to say that we do not recall you contacting us - I assure you we would have followed up any request you might have made. Eight or nine years ago the HC had not run and we could not be sure that it would run - certainly we were not expecting the fuel-saving effects to be so pronounced.
    You were probably unaware of the earlier (Type 1) cam at the time. You could have made one of these back then. This is actually the Type that we are investgating the possibility of making aftermarket cams for. The HC is a possibility for the SR but still would be a very ambitious project for us - the helical machining was tricky enough for two cylinders let alone four. But once a CNC example was made I would imagine copies would be fairly straightforward.

    Perhaps you could contact us through the address given on the website. We would also be interested in whatever SR parts you have for sale - especially heads and valve gear etc.

    The reason the magazine ("Performance Buildups") did not do any follow-ups was that the editor, Paul Tuzson left the magazine and I think it finally stopped being published.

    As an aside here - I think Paul is probably one of the best writers/photographers on automotive technology in the world - it is a shame we don't see more of his work.

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    Quote Originally Posted by Sheepdog View Post
    It looks like the earlier attempt at posting a new thread did suddenly "pop up" - sorry about that.
    Your a new person so your posts had to be approved. Sorry for the delay
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    they haven't actually made one for the VE head have they?
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    waste of time. many superior models out there.

    Kudos for the development to him.

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    Quote Originally Posted by Autech View Post
    waste of time. many superior models out there.
    care to explain?
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    Quote Originally Posted by wnwright View Post
    I'm sorry I'm an engineer. I'm looking at the math.

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    You cant effecitvely introduce a variable lift from this setup.

    So you are left with a massive variable duration at a fixed lift.

    Certainly its great in that it can pick up air speeds a cylinder filling dynamics with a duration control, but you really need to get a lift option in there to get any effective gain in top end. For econobox style engine this is a great idea, and certainly for engines that are looking to perform better in mid to lower range with targets of fuel economy and increases in torque.

    Anyone with an engineering degree will realse flow dynamics are not going to be ideal and at every given value of lift and valve surface area, you can only have a given range of flow volume. From a performance view (with racing and top end and continous power in mind, it will be very limited). Of course one could design the cam to tolerate a big lift to begin with - but at the cost of torque and horsepower through midrange and bottom end.

    Sure increasing duration will give you the theortical ability to have a MUCH higher rpm band, but engine dynamics fall off etc etc.

    It does say on a website regard the WHC:

    "In its ultimate form, the Williams Helical Camshaft can give a conventional car engine better than F1 performance with fuel economy rivalling that of a diesel."

    and....

    "These seemingly outlandish claims are backed by sound, conventional automotive engineering theory. Given that a suitable variable duration arrangement does exist, there are few engineers who would disagree with these claims. "



    I dont understand how it can give better than F1 performance? Fuel economy rivalling that of a diesel is also a big call. Diesel engines, especially turbocharged diesel engines, are near the ultimate in fuel efficiency. Diesel technolgy has pretty much blown petrol combustion engines out of the water and it wont be long before we see these in mass produced vehicles. Im definately all for hearing their theories and open to ideas
    Last edited by Autech; 03-09-11 at 07:11 AM.

  11. #11
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    Quote Originally Posted by Autech View Post
    You cant effecitvely introduce a variable lift from this setup.

    So you are left with a massive variable duration at a fixed lift.

    Certainly its great in that it can pick up air speeds a cylinder filling dynamics with a duration control, but you really need to get a lift option in there to get any effective gain in top end. For econobox style engine this is a great idea, and certainly for engines that are looking to perform better in mid to lower range with targets of fuel economy and increases in torque.

    Anyone with an engineering degree will realse flow dynamics are not going to be ideal and at every given value of lift and valve surface area, you can only have a given range of flow volume. From a performance view (with racing and top end and continous power in mind, it will be very limited). Of course one could design the cam to tolerate a big lift to begin with - but at the cost of torque and horsepower through midrange and bottom end.

    Sure increasing duration will give you the theortical ability to have a MUCH higher rpm band, but engine dynamics fall off etc etc.

    It does say on a website regard the WHC:

    "In its ultimate form, the Williams Helical Camshaft can give a conventional car engine better than F1 performance with fuel economy rivalling that of a diesel."

    and....

    "These seemingly outlandish claims are backed by sound, conventional automotive engineering theory. Given that a suitable variable duration arrangement does exist, there are few engineers who would disagree with these claims. "



    I dont understand how it can give better than F1 performance? Fuel economy rivalling that of a diesel is also a big call. Diesel engines, especially turbocharged diesel engines, are near the ultimate in fuel efficiency. Diesel technolgy has pretty much blown petrol combustion engines out of the water and it wont be long before we see these in mass produced vehicles. Im definately all for hearing their theories and open to ideas
    You are still not explaining why this could not be applied to a VVL setup. Is it simply that there is not enough space for 16 mechanisms, that is, 1 for each cam lobe?

    By the way, I do hold an engineering degree. Also, most engineering degrees do not involve flow dynamics.
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    Quote Originally Posted by wnwright View Post
    I'm sorry I'm an engineer. I'm looking at the math.

  12. #12
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    Quote Originally Posted by Will View Post
    You are still not explaining why this could not be applied to a VVL setup. Is it simply that there is not enough space for 16 mechanisms, that is, 1 for each cam lobe?

    By the way, I do hold an engineering degree. Also, most engineering degrees do not involve flow dynamics.
    My studies of mechanical engineering involved flow dynamics and such

    It can not be done to a VE camshaft. The system patented can only run on a single lobe height lift. Swtiching to the WHC patents would mean going back to a single lift cam.

    Small gains could be had on a DE motor, but not on a VE motor. Like i have said, duration is great for high RPM and getting flow dynamics happening and chamber speeds up, but without lift - from a performance horsepower view - its near waste of time.

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    Quote Originally Posted by Autech View Post
    My studies of mechanical engineering involved flow dynamics and such

    It can not be done to a VE camshaft. The system patented can only run on a single lobe height lift. Swtiching to the WHC patents would mean going back to a single lift cam.

    Small gains could be had on a DE motor, but not on a VE motor. Like i have said, duration is great for high RPM and getting flow dynamics happening and chamber speeds up, but without lift - from a performance horsepower view - its near waste of time.
    Right, and mechanical engineering is one of over 20 different kinds of engineering degrees, most of which do not include flow dynamics. You STILL have not said WHY these mechanisms could not be adapted to all 16 lobes of a VVL system.
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    Quote Originally Posted by wnwright View Post
    I'm sorry I'm an engineer. I'm looking at the math.

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    Will...

    Forget the idea of having a WHC on the VE head. It cannot be done. I've said above why, but you need to think outside the box.

    1) There is not enough room horizontally in the head between the cylinders to accept variable duration lobes.
    2) Even if the progression rate could be made tight enough, you then have the issue of the second lobe with the biger lift ( and sufficient room to provide a variable width [duration] lobe and THEN have the mean of acutating it. Keep in mind the High cam on the VVL camshaft is between both the low lobes. Changing this configuration would mean change the rocker design, changing the hydraulic locking design and replacing the rocket pivot tube with a tube having suitable oil feeds.

    3) Even if we theorise its somehow possible to have both HIGH and low lobes operating in WHC style. Ignoring rocker orientation and design and just looking at the cam itself. You would have to have an inner and outer tube consisting both of WHC .You would then have to run two different base circles. To compensate for the difference in base circles youwould need to change rocker height and length, and even then your rocker ratio would be thrown way out of effective means.

    I cannot see how its possible to work on a VE head retaining dual lift heights. Hope I've made it clear enough why i beleive it wont work on a VE engine with dual lift heights for you. If your an engineer, you should have figured this out already before i typed this, and im assuming youve looked at a VVL head right?

    Like i have said above, this can be made to work for a DE head NO PROBLEMS. For someone who wants great torque and effiency down low not a problem - would work fantastic!

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    Quote Originally Posted by Autech View Post
    Will...

    Forget the idea of having a WHC on the VE head. It cannot be done. I've said above why, but you need to think outside the box.

    1) There is not enough room horizontally in the head between the cylinders to accept variable duration lobes.
    2) Even if the progression rate could be made tight enough, you then have the issue of the second lobe with the biger lift ( and sufficient room to provide a variable width [duration] lobe and THEN have the mean of acutating it. Keep in mind the High cam on the VVL camshaft is between both the low lobes. Changing this configuration would mean change the rocker design, changing the hydraulic locking design and replacing the rocket pivot tube with a tube having suitable oil feeds.

    3) Even if we theorise its somehow possible to have both HIGH and low lobes operating in WHC style. Ignoring rocker orientation and design and just looking at the cam itself. You would have to have an inner and outer tube consisting both of WHC .You would then have to run two different base circles. To compensate for the difference in base circles youwould need to change rocker height and length, and even then your rocker ratio would be thrown way out of effective means.

    I cannot see how its possible to work on a VE head retaining dual lift heights. Hope I've made it clear enough why i beleive it wont work on a VE engine with dual lift heights for you. If your an engineer, you should have figured this out already before i typed this, and im assuming youve looked at a VVL head right?

    Like i have said above, this can be made to work for a DE head NO PROBLEMS. For someone who wants great torque and effiency down low not a problem - would work fantastic!
    Thanks, I appreciate the thorough explanation. I have never internally examined or owned a VE head. I assumed from the beginning that is was mostly a matter of space, and had also not considered the requirement of gears between each lobe which creates the inherent interference with lobe switchover.
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    Quote Originally Posted by wnwright View Post
    I'm sorry I'm an engineer. I'm looking at the math.

  16. #16
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    Quote Originally Posted by Autech View Post
    You cant effecitvely introduce a variable lift from this setup.

    So you are left with a massive variable duration at a fixed lift.

    Certainly its great in that it can pick up air speeds a cylinder filling dynamics with a duration control, but you really need to get a lift option in there to get any effective gain in top end.
    That's not exactly true. For those of us interested in performance, you could easily have a very high lift (and ramp up angle) and just control idle and low rpm power production with very short durations. Not sure if you'd have an issue with valve float though at the very short duration periods.

    This was discussed in the previous thread as well.

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    Welcome to the forum Sheepdog. I can't speak for everyone, but there are quite a few people I think with N/A and turbo SR20DE engines out there that might be interested and have the money to put down for a drop-in cam that gives them lift similar to a Jim Wolf Technologies C2 or C3 cam (very aggressive race cams) but with variable max lift duration to keep idle speeds low and under control, and power production healthy at the low and mid rpm range. They might be unable to afford the money, time or effort into converting to a SR20VE engine or head (classic two-stage variable lift and duration) but could swap in cams and stiffer springs no problem (depending on price).

    I don't want to get your hopes up though, we're also a traditionally frugal crowd. We like to see documented power gains (economy appeals to a much smaller portion of our base) and assurances that equipment will last many tens of thousands of miles with trouble-free operation. You'd have to determine at what durations and rpm valve float might become an issue on stock springs and certain aftermarket springs. You'd also have to determine what duration causes valve/piston collision and maintain a margin of safety there since our engines are of the interference type. Keep in mind our engines run to 7,500 rpm from the factory, and many of us like to go even higher than that.

    It's a tall order for sure.
    Last edited by BenFenner; 03-09-11 at 12:06 PM.

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    I think the design is an awesome idea, I would definitely love to see some R&D put into the SR20 for something like this. Thanks for taking the time to notice our community and reach out to us Sheepdog, I hope we are able to work closely with you guys on something like this. Cams are definitely one of the next big things on my list, and I've been reading up on all the options available to us. The hardest thing for me to get over though is the loss of torque and bottom end with a set of big cams. That's why I love the idea of what your HC cams are doing.
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    Quote Originally Posted by Sheepdog View Post
    Kiwi - I am afraid that (after much head-scratching) I have to say that we do not recall you contacting us - I assure you we would have followed up any request you might have made. Eight or nine years ago the HC had not run and we could not be sure that it would run - certainly we were not expecting the fuel-saving effects to be so pronounced.
    You were probably unaware of the earlier (Type 1) cam at the time. You could have made one of these back then. This is actually the Type that we are investgating the possibility of making aftermarket cams for. The HC is a possibility for the SR but still would be a very ambitious project for us - the helical machining was tricky enough for two cylinders let alone four. But once a CNC example was made I would imagine copies would be fairly straightforward.

    Perhaps you could contact us through the address given on the website. We would also be interested in whatever SR parts you have for sale - especially heads and valve gear etc.

    The reason the magazine ("Performance Buildups") did not do any follow-ups was that the editor, Paul Tuzson left the magazine and I think it finally stopped being published.

    As an aside here - I think Paul is probably one of the best writers/photographers on automotive technology in the world - it is a shame we don't see more of his work.
    Thank you for your reply. What happend innitially was I was living in New Zealand at the time. I have read the whole article and was blown away with what has been documented with these cams.
    As there was no contact particulars from the magazine, I have send an email to the editors of that magazine and their reply was that the vendor was merely looking at marketing these cams in conjunction with a major car manufacturer.
    At no stage did they try and put me in contact with you guys and they said that I should just keep on looking for a follow up or progress wich never happend.
    I would have a spare cyl head for sale very soon and will contact you when it is available
    Gerry

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    Comments on the various points raised so far:

    Lack of ability to vary lift - both I and the inventor take a fairly basic view of what cams actually do. We both consider that variable lift in a performance context really has little effect. I think the main reason that both Nissan and Honda (on the VTEC) have a lower lift on the shorter duration lobes is simply due to the fact that having more lift would not help the volumetric efficiency at the lower RPM where these lobes are being used - there being no point in stressing the various valve train components for no gain. If there is a good reason for variable lift perhaps you could enlighten us.
    Remember that one of the basic ideas behind the HC is that the lobe lift need not be particularly high - having any amount of duration available basically removes the need for extreme lift.

    The statement involving F1 performance and diesels etc:
    There is a bit of copywriters' hyperbole here but the statement is also true(ish). The "F1" part is simply that the HC can supply enough duration to essentially match any RPM no matter how high and retain the standard lower duration. The "diesel" part of the statement refers to the possibility of controlling part load by LIVC combined with a very high CR (14:1?, 16:1?) and operating the engine in an Atkinson Cycle fashion. Any problems with detonation can be handled by lowering the compression pressure by LIVC. We have actually done both of these things - but not in the same engine. I am fairly confident that the overall fuel economy would be as good as the typical car-type diesel. Maybe not as good as the best of big truck or turbo diesels - but pretty good.

    On the question of converting every VE lobe to a Type 1 or Type 2 (HC):
    Theoretically it could be done (especially to the Type 1 lobe). It is a matter of complexity mainly. The main reason we are focussing on the SR engines is that only having four lobes per camshaft greatly simplfies the system. A VE would require twenty-four lobes to be converted - a DE just eight. As written above, we also think that there is little point in having variable lift. We have done cams with two, six and twelve lobes - four should not be too difficult.

    Autech - your statement "Many superior models out there" - perhaps you could name a few - there actually are none at all that can match the HC.

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    Thank you Kiwi - that explains it - if PB magazine had passed on the message motoring history may be different now (or maybe not).

    Ben - the economics of the whole variable cam business is the a problem. For quite a few years we have had the potential to make simple Type 1 cams for the Daihatsu Charade and SOHC Ford sixes. The problem is that both of these types of car are obsolete now. A Type 1 cam for either would cost (with centrifugal controller) maybe $1500 to $2000 (this is what it cost to make them). This typically would be about three times the price of the whole Ford or Charade - hard to justify spending more money on the cam than the whole car is worth. However I don't know much about business or economics - maybe the cams could be made in China for $500 or so. But then there maybe quality problems - you don't hear much about Chinese cams.

    Are SR engines still being made?

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    Quote Originally Posted by Sheepdog View Post

    Are SR engines still being made?
    Unfortunately not
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    Quote Originally Posted by wnwright View Post
    I'm sorry I'm an engineer. I'm looking at the math.

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    Quote Originally Posted by Sheepdog View Post
    Thank you Kiwi - that explains it - if PB magazine had passed on the message motoring history may be different now (or maybe not).

    Ben - the economics of the whole variable cam business is the a problem. For quite a few years we have had the potential to make simple Type 1 cams for the Daihatsu Charade and SOHC Ford sixes. The problem is that both of these types of car are obsolete now. A Type 1 cam for either would cost (with centrifugal controller) maybe $1500 to $2000 (this is what it cost to make them). This typically would be about three times the price of the whole Ford or Charade - hard to justify spending more money on the cam than the whole car is worth. However I don't know much about business or economics - maybe the cams could be made in China for $500 or so. But then there maybe quality problems - you don't hear much about Chinese cams.

    Are SR engines still being made?
    Althoug the SR engine is no longer in production, I would suggest that its use by date would last for at least another 10 years.
    If you guys are interested to have a good look at a VE cyl head, I would have one in a couple of weeks. I would freight it to where you are located with the understanding that I will get it back unless you want to purchase it if needed to mill or cut away components not needed.
    Give me a call on my mobile or send me a PM
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    Gerry

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    If you are going to make the cam you make it for the de. There are plenty of de's out there in all forms, rwd and fwd. Plus these are still at least a decade away from death or more. IMO there are simply not enough ve engines produced to consider making this cam for a ve engine. That and the fact the ve also has duel lobes so the benifits would be less.

    so

    from a marketing point de wins. (bigger market)
    from a production point de wins. (easier to adapt)
    from and increase in benifits over stock point of view de wins again.

    i dont see the variable lift being too much of an issue. Yes variable lift is good. But look at the tomei pon cam, it still runs 11.5mm lift and only 256 duration spread this to 280-300deg and you have a decent cam there.

    I think the key in designing the cam should be kept simple;
    Run a fair wack of intake advance to aid low end response and keep detonation down, then add duration to get the top end back.
    shoot for poncam response with a typical stage 3 cam top end, this way you can easily run 12mm lift. That level of lift wont cause too much of a prob down low and wont restrict you top end.

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    I don't see a $1,500 cam going over very well at all here. =(

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    Quote Originally Posted by BenFenner View Post
    I don't see a $1,500 cam going over very well at all here. =(
    through economies of scale if you can get that figure closer to the $1000 mark i do see a lot of drifters buying it

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    Yah the RWD market would certainly be the place to go. They might be able to swallow a $1k cam that gives them big benefits. However "economy of scale" is way easier to say than it is to do. Need to find a place willing to do a relatively small production run, with high quality (AKA not China).

    (FWD cams and RWD cams are identical except for the length of a single dowel pin I believe.)

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    Quote Originally Posted by BenFenner View Post
    Yah the RWD market would certainly be the place to go. They might be able to swallow a $1k cam that gives them big benefits. However "economy of scale" is way easier to say than it is to do. Need to find a place willing to do a relatively small production run, with high quality (AKA not China).

    (FWD cams and RWD cams are identical except for the length of a single dowel pin I believe.)
    true that, easier said than done. Not impossible however.

    yeah, i think its fwd can ca go into rwd but not the other way due to no provision for the dissy.

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    I think it would have to be the DE.

    All this discussion about cost of the cam etc. is, of course, the main point. There is no question that the various cams work well - but could they be made cheap enough?

    Another economic factor is the legal position - if the cam is blamed for an accident or an engine blowup - we really don't want to put ourselves in this sort of legal position.

    Would the cams actually be legal with regard to emission laws etc.? Once again we really don't want to put ourselves in a dodgey legal position.

    It is questions like this that have held up progress rather than actual mechanical problems.

    This is also why we have tried to become associated with a much bigger company who would have more experience with the legal and economic hurdles.

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    Quote Originally Posted by Sheepdog View Post
    I think it would have to be the DE.

    All this discussion about cost of the cam etc. is, of course, the main point. There is no question that the various cams work well - but could they be made cheap enough?

    Another economic factor is the legal position - if the cam is blamed for an accident or an engine blowup - we really don't want to put ourselves in this sort of legal position.

    Would the cams actually be legal with regard to emission laws etc.? Once again we really don't want to put ourselves in a dodgey legal position.

    It is questions like this that have held up progress rather than actual mechanical problems.

    This is also why we have tried to become associated with a much bigger company who would have more experience with the legal and economic hurdles.
    I think the legal issues are pretty simple. You just have to state, like any performance company does, that the cams are to be used at your own risk and are for off-road use only.
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    Quote Originally Posted by wnwright View Post
    I'm sorry I'm an engineer. I'm looking at the math.

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    Quote Originally Posted by Sheepdog View Post
    I think it would have to be the DE.

    All this discussion about cost of the cam etc. is, of course, the main point. There is no question that the various cams work well - but could they be made cheap enough?

    Another economic factor is the legal position - if the cam is blamed for an accident or an engine blowup - we really don't want to put ourselves in this sort of legal position.

    Would the cams actually be legal with regard to emission laws etc.? Once again we really don't want to put ourselves in a dodgey legal position.

    It is questions like this that have held up progress rather than actual mechanical problems.

    This is also why we have tried to become associated with a much bigger company who would have more experience with the legal and economic hurdles.
    No aftermarket camshaft is going to comply with emmission laws, full stop.
    Emmission laws are directed at car manufacturers and the car manufacturer are only liable to comply with those laws whilst the car is used as a " factory equipped"
    A lot of aftermarket and performance parts are normally sold with the understanding that it is intended for motorsport and wont necessary meet local authorities standards.
    Once the owner of that car go and modify it, it is up to the local traffic authority to ensure that it polices the owners and users by means of various emissions tests.
    I still dont see the issue with having these cams developed for the VE head, as if you do go that route, it would be a single lobe per cyl as the HC will take care of the duration and timing events.
    I have seen a VE head with some major changes where only one lobe is used with a killer camshaft due to the superior flow capacity over a DE cyl head.
    We all know that the VE have a superior valve train over the DE and are limited by max Rpm's to cam profile design, ramp angle etc.
    I am still willing to borrow you guys a VE cyl head.
    Gerry

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    Kiwi - thank you for your information which is very helpful.
    From what you say a VE head could fitted with with DE cams and valve gear. From what other people were saying I thought that this was not possible.
    If it is possible it would mean that a variable cam developed for a DE would fit a VE anyhow.
    Remember that, at present, we have very little first-hand knowledge of SR engines at all.
    We are very wary of becoming involved in a big (and expensive) project - and an SR project would be just that. We have all ready spent a lot of money on three prototypes that were demonstrated to run perfectly well which resulted in basically absolutely no profit to us. We really don't want this to happen again.
    We are starting to think that the manufacture and marketing of a simple two-lobe Type 1 cam-and-controller for a single cylinder motorbike engine may be the best option. If this works out maybe we can progress to more ambitious projects like SRs or whatever.

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    Quote Originally Posted by kiwi-japie View Post
    I still dont see the issue with having these cams developed for the VE head, as if you do go that route, it would be a single lobe per cyl as the HC will take care of the duration and timing events.
    Which follower does the single lobe actuate? The center follower, or the side two followers? If you're talking about the center follower, something must be done to lock it into active mode (instead of passive mode) 100% of the time instead of activated by oil pressure.

    Quote Originally Posted by kiwi-japie View Post
    I still dont see the issue with having these cams I have seen a VE head with some major changes where only one lobe is used with a killer camshaft due to the superior flow capacity over a DE cyl head.
    You sure it was one lobe (the center lobe)? You sure it wasn't two side lobes?

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    Quote Originally Posted by BenFenner View Post
    Which follower does the single lobe actuate? The center follower, or the side two followers? If you're talking about the center follower, something must be done to lock it into active mode (instead of passive mode) 100% of the time instead of activated by oil pressure.

    You sure it was one lobe (the center lobe)? You sure it wasn't two side lobes?
    It was using the 2 outside lobes and the centre lobe was grinded away, however there is the possibility to lock the mechanism mechanically and use the 1 centre lobe if needed.
    I am not saying this will work without fail but maybe worth the while investigating the possibility

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    Isn't the point whether the DE cams and DE type of rockers can be fitted to a VE head without machining etc.? That's what I want to know.

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    Quote Originally Posted by Sheepdog View Post
    Isn't the point whether the DE cams and DE type of rockers can be fitted to a VE head without machining etc.? That's what I want to know.
    Not without any machining. DE uses a hydraulic lifter on the non Roller rocker and the VE and later SR DE's using a roller rocker.
    When Reg Cook ( Cook Motorsport in New Zealand ) used a VE head years back for his project drag GTI-R there were no aftermarket camshaft suppliers for the VE. He chose to use the VE cyl head due to the superior flow capabilities and valvetrain reliability.
    He used a DE camshaft for his build and had some tricky engineering and machining done in order to make this all work.
    Where I see this all now is as follows.
    When using a VE head, there is no need for a secondary lobe, eliminating high lift as I believe with the patented HC cam there is no need for it.
    If the HC cam will work in a DE it will work in a VE head provided that there is no secondary lobe. Wether you eliminate the outer lobes and lock the device to run from the centre high lobe or remove the centre lobe depends on how much room you need to make the device work
    The same cam or billet wont work in both as the cam journals of the 2 are not the same nor will the rocker ratios be the same.
    You can not use the DE rockers in a VE and vice versa.
    I think the only way you will know is if you inspect a VE head.
    My offer still stand to freight a head out to you when I have it availble
    Gerry

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    Quote Originally Posted by Sheepdog View Post
    Kiwi - thank you for your information which is very helpful.
    From what you say a VE head could fitted with with DE cams and valve gear. From what other people were saying I thought that this was not possible.
    If it is possible it would mean that a variable cam developed for a DE would fit a VE anyhow.
    Remember that, at present, we have very little first-hand knowledge of SR engines at all.
    We are very wary of becoming involved in a big (and expensive) project - and an SR project would be just that. We have all ready spent a lot of money on three prototypes that were demonstrated to run perfectly well which resulted in basically absolutely no profit to us. We really don't want this to happen again.
    We are starting to think that the manufacture and marketing of a simple two-lobe Type 1 cam-and-controller for a single cylinder motorbike engine may be the best option. If this works out maybe we can progress to more ambitious projects like SRs or whatever.
    dont take this the wrong way, but this does not surprise me considering the 3 engines you decided to use

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    Bluebird - it was not taken the wrong way. It is just that those three engines were the most suitable for building the various prototypes - but clearly they were not the best commercial choices.
    We thought that we would only have to demonstrate that the variable cam principles worked well to have car manufacturers falling over themselves to give us money but it didn't (or hasn't yet) happened.

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    Have a look at this computer animation of the HC which has just appeared on the internet:
    YouTube - Helical camshaft

    We have no idea who made it but they certainly have a lot more computer skills than us.

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    I probably should point out that although this animation shows the principle very nicely it is slightly misleading. The overall lobe shape is a bit unnatural and distorted and, possibly more important, the lobe rotates in the wrong direction. The intention is that the "solid" (stronger) part of the lobe contacts the follower first.

 

 

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