1. Musk

    Musk Member

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    I would love to find out the horsepower and torque curve all of this combination. I guess it will be something I will really never know. Although the Machinist I am bringing my block 2 as a Dino.
     
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    • Jim Kueneman

      Jim Kueneman FABO Gold Member FABO Gold Member

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      The example he has in his book are big block Chevys (BB MOPAR would be similar) is he runs 106 LSA and he gets questions on that choice when most are running 112-114. The ratio of valve to cubes per cylinder in BB are such that you can run 106 and have it run and idle fine and make better power across the band than a 112 LSA, according to him.

      His method is based on his experience and realizing the LSA is selected based on the ratio of how much air a cylinder can hold (engine size) and the amount of air that is available to charge it (valve size). With an assumption of how well the head can flow. His graphs assume a “normal” type head. A known poor head would reduce flow and tend to tweak the LSA up and a great head would flow more tweak the number down.
       
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      • Jim Kueneman

        Jim Kueneman FABO Gold Member FABO Gold Member

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        I went back and looked at the cam I put in the stock 318 Coronet. Good grief it is a 112 LSA and with those heads it should be 106-107 and with the low compression it should have been 105-106. No wonder I have always been totally dissatisfied with it beyond a cruiser. The Duster and Toth heads on the 318 should have been more like 110! Now I want to get new cams for those 2 cars! The 225 /6 I used Vizard and a simulator to choose the cam and it pulls stumps. Need to make the right choice on the 360 for the Valiant now.
         
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      • 1Badcolt

        1Badcolt Well-Known Member

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        You looking real good [ power to weight ratio ]
         
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        • 1Badcolt

          1Badcolt Well-Known Member

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          Alabama car owner !!!
           
        • 1Badcolt

          1Badcolt Well-Known Member

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          Mr Gasket [ lug nuts ]
           
        • 1Badcolt

          1Badcolt Well-Known Member

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          Call Racer Brown - he will sale you want you [NEED].
           
        • rumblefish360

          rumblefish360 I have escaped the evil Empire State! FABO Gold Member

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          I say do it haphazardly so everyone can see the difference between a wiser choice and a off the shelf choice.

          Then follow is excellent advice on a pressure wave cancellation box.
           
        • Jim Kueneman

          Jim Kueneman FABO Gold Member FABO Gold Member

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          If you believe Vizard's reasoning that is what would be expected as today's high flow 4 valve per cylinder and CFD modeling of intake air flow will drive much higher LSA numbers for optimal engine operation per his charts. One of his examples is a 4 valve 2.2L that calculates out to a LSA of 118 degrees because it can flow so much more air compared to the volume of the cylinder
           
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          • Jim Kueneman

            Jim Kueneman FABO Gold Member FABO Gold Member

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            Here is an example of just LCA comparison and as stated here tighter LCA is more power but the same conclusion that the low LCA equals bad idle. What is not understood here is if you look at overlap the cams crossover from mild to race! For a 101 LCA a 236 duration is a full on race cam in the overlap world. 112 is a hyper mild driver cam and 107 is a street cam. Exactly what they stated. They need to drop the duration of the 101 LCA to get a street cam overlap and do this again.

            Camshaft Shootout: Lobe-Separation Angle Tested and Explained
             
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            • Bewy

              Bewy Well-Known Member

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              Jim K,
              Vizard's advice is spot on, as you found out. His 128 rule is used for parallel valve heads, staggered valve like the BB Chev uses 131.5.

              I am sure Racer Brown grinds good cams. As does isky, Comp, Howards etc.....

              But how many of these cam grinders actually grind cams on various LSAs & then dyno test them? Especially Mopar cams. Did someone say zero.....
              Vizard has done exactly that, about 19,200 dyno pulls while under contract at Crane cams. And 0000s more outside of Crane.
               
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              • Jim Kueneman

                Jim Kueneman FABO Gold Member FABO Gold Member

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                So here is something from a group. The 128 rule does not take into account a few factors that could change things a bit. Here is the full story:

                The 128 #
                Sorry about the length of this introduction here but I need to make it clear that I have remained a freelance writer so that I never have see results distorted to gratify the advertising department.

                You would think after over 120 years that valve events required to produce maximum torque at any given engine speed would be well understood. It seems not so. There was a post a while back suggesting that if we called a number of cam companies (about 10 as I remember) we were likely to get about 10 different cam specs. Well Stan Weiss did that and guess what? Whoever posted that idea of calling ten cam companies was right – all of Stan’s responses from the cam companies were different. (surprise surprise!) Now let us assume that one of them was right (and that is an assumption that is stretching the point) If one cam company was right then that means that, by default, nine are wrong. If you do not know which one is right because they all claim to be then you have only a 1 in 10 chance of getting the right cam. If that sounds bad then let me tell you my research over 2 decades has shown that 95% of the cams sold are at least 5% shy of making the output both in terms of torque and HP that they could do. This means that the 10/1 street 350 you have just sunk your last dime into is only making 415 lbs-ft instead of 435. And just as important the cam you bought that was 20 lbs-ft down cost exactly the same as one ground with the right valve events. This means that the one section of the performance community and the biggest, that is the guys with limited budgets, are the ones that are being short changed.

                Now before it becomes a subject of posting questions let me say that the ‘128’ number is for parallel 2 valve engines such as SB Chevy’s, Fords and Chryslers with typical (average) discharge co-efficient’s in the 0.000 to about 0. 200 thou valve lift range. It is also for a base 10.5/1 CR engine but I will explain that and how to cater for other CR’s later.

                This means it is not for Hemi’s, 3 and 4 valve engines and the like (although I could develop one for either of this group of engines) Also let me point out that I have introduced this method of selecting the primary valve event number so that guys who do not have or cannot afford a flow bench (I compute my cams from flow #’s) are far less at the mercy of the cam companies desk jockey. If you don’t like the result this simple formula predicts you can go back to the cam company of your choice and settle for their best guess intead! It is entirely up to you.
                Anyone who has spent time with me or been to any one of my university seminars very quickly realizes I am very adamant about the cam tech I deliver, especially so since much of it is contrary to what we may term ‘common wisdom’. What makes me so certain that what I am delivering is right?
                Best I put this up front so you know where I am coming from as tech journalists typically don’t exactly have a reputation of knowing that much on the subject or even having it right.

                First off I am not a journalist - I am a qualified ex aerospace research engineer who is overwhelmingly interested in motor racing. I built my first flow bench in 1958 at the age of 15. The heads I worked on when I first started were those for the BMC ‘A’ series head designed by Weslake and used, among other things, on cars such as the Mini Cooper, Frog Eye Sprites and the like. I got really good at this and engines I built started winning races and championships. So head technology was being acquired swiftly and by the bucket load. I even had heads for V8 engines score victories on the international scene to the extent of having huge orders that I could not even begin to deal with. About that time I had a serious lung illness brought on by iron grit (mask was not working as well as it should have) . It affected me much more than would have normally been the case as I had already only half the normal lung capacity due to a tropical infection. This caused me to cut down on porting to the point that I could not earn a living at it. Fortunately the UK’s then premier performance magazine approached me to write tech features for them. In essence I slid sideways into this second career almost by accident but within 2 years I was the most widely published automotive tech writer in Europe.

                The ‘A’ Series race engines I was building from about 1963-64 on used cams designed in the USA but produced in the UK. With such I won races but when I tried cams done locally they somehow failed to deliver as effectively. So about 64-65 time I started looking into why a given spec of engine might want to have certain event characteristics. A short while before being asked to write for the afore mentioned magazine I was campaigning a 10,500 rpm 1000 cc Mini Cooper ‘S’ road racer with a friend. This motor was very much on a budget but was quite competitive against other 5 port ‘A’ series powered mini’s. However it kept eating valve springs and retainers. I asked around and no one seemed to have a satisfactory solution even if they knew what the problem was. So I called Harvey Crane at his shop in Hallandale Florida. The cost per minute for a call from the UK to USA was in pounds per minute so it was a pricy call. I was very surprised to get Harvey on the phone as I figured he would not know who this young punk engine builder calling him from the UK was. Well Harvey gave me all the solutions to my problems bar one. He said that for this remaining problem he would have to look into it and would call me back. Much to my amazement about a week later he called back (at a cost of about $1.50 a minute) and gave me the final fix for the issues I had. A short while after that my partner and I started experimenting with cams other than the tried and true cam we were using in out 1000. We ran about 6 different cams through three different sizes of ‘A’ series engines. A somewhat fuzzy pattern started to emerge from these tests but the most important this that I learned was the I was nowhere near being an expert on valve events and nor was anyone else among the then distinguished race engineers that I then knew including world championship winning F1 engine designers. About this time was when the magazine asked me to write for them. Well I could keep them supplied with flow and dyno features for a good while but eventually I would have to be able to talk about cams at a level of a top professional engine builder. Over the years I got to do cam testing with Harvey Crane and Sig Erson (who actually crewed for me once while I was racing in the British Touring Car Championship) who became quite a close friend of mine. Also I tested cams done by several UK companies including Cosworth. So my knowledge of what was likely to work and what was not started to have some significance but I sure did not have all the answers by any means.
                By 1980 my desire to present functional technology to my readers (I was now writing for about 12-14 magazines every month) I moved to Riverside Ca and set up shop with a SuperFlow dyno (#3) a new flow bench, milling machine, valve and seat machine, lathe etc. and started to test US produced aftermarket products. Boy did that reveal a lot of advertising BS. In 1981 I had a story in PHR published called “The Great Nitrous Oxide Shootout” It showed some fraudulent claims were being made and it also caused a contract to be put out on my life.
                A while after that I got a call from Harvey Crane who had by this time become a close friend, who suggested that we have a giant cam test not in just one but multiple engines. Over a period of a couple of years cams were run through three displacements of Chevy engines with three specs s of heads from stock through pocket ported to race spec and at two – sometimes three chamber sizes for different CR’s.
                These tests produced meaningful results from over 8000 combinations (before I hear any responses about not having enough time to do that many tests it will be best if you read how these tests were done exactly what a ‘combination’ was).

                A short while after this I was asked to update the specs for a range of cams for Piper cams in the UK. Their sales of my more powerful spec cams about doubled their sales. About a year or so after that Kent Cams, the other major cam company in the UK asked me to see what I could do for their cams. After a period of a couple of years I and my team ran over 11,000 cam combinations in about 5 different engines. The results of these test showed so much power increase over the cams for the motors concerned that their introduction almost bankrupted Piper cams and boosted Kent to the # one cam company in Europe.

                I can say with a great deal of certainty that the group I headed here has tested more cams than any other group on the face of the planet. If you want to find out what others have done to rival this be my guest.

                Also In closing for those of you that still don’t want to take the results I am going to present in this series of posts then do yourself a favor - call Mike Jones as his cams turn out real close to mine in most cases. I am sure that there are other experts out there but trust me they are far less common than you might think hence the fact that 95% of cams are wrong.

                OK that made a start on this 128 # but before you all go posting stuff remember the more questions you ask at this point the longer it will take for me to get to the nitty gritty in part II.
                DV

                128# part II
                So here I am with a ton of flow bench and head expertise and a whole lot of race wins to back that up including two British Touring Car Championships (Did the heads and carbs and advised on the cam specs) but to my mind still woefully short on valve event knowledge. Here was my dilemma. Too many times the cams I tried in engines I had built, which with the airflow they had, should have made more hp by virtue of a higher specific torque (Torque per cube) output. Unlike most of folk I have a dyno (or at the very least full access to one) but even so testing two or three cams (sometimes more) was, to say the least, inconvenient.

                The magazines paid me by the page not by the hour for all the dyno time I put in. In fact 98% of that dyno time was not paid for by the publisher of whatever feature/book I was doing. I personally carried the burden of the testing. This meant that I needed to know beforehand what cam event timing would likely be optimum for the engine I was building.

                Very early on I found that accurate cam event timing advice was thin on the ground. Unlike most engine builders my work became public domain. If the engine build I was writing up did not perform – well guess who would carry responsibility for that! Bottom line here is since I could not rely on the advice of others I thought I had better become an expert by one means or another.

                The tests that Harvey funded proved to be an educational turning point. After doing all these tests and compiling the data it became evident that a well-defined, though complex pattern was emerging. By about 1995 I had over 20,000 meaningful tests. Using this data I started to construct empirical formulas from data that would predicted the data curves.

                Slowly, by piecing together data curves and the relative influence they had on each other I could back calculate the results seen by the test engines and anything between those tests. This is where MS Excel really came in handy. About 1998 I was ready to start field testing the program. This I did with my good friend Denny Wycoff at MM&S in Tucson. Denny (now retired) dealt with a lot of successful racers many of which held track records. I can’t recall a single instant where the computed cam did not go faster. So the program (which became COS-Cam) was proving itself pretty well but before going into any more detail let me say that the tests debunked quite a few commonly held beliefs.

                The first of these is that the commonly held belief that the intake closure point is the most influential valve event on the engines output is totally wrong. Yes I know that the much revered Charles Fayette Taylor in his two books totaling about 1350 pages states this is so but his tests were done on low rpm aero engines with non-scavenging exhaust of the WWII era not the high rpm scavenging header equipped ones we have today.

                Secondly the LCA is, for the most part, not an adjustable element, that is unless you want to stray off optimum and give up torque and power. Take a look at the graph. Study it for a while and you will see that a 108 Lobe Centerline Angle (also called a Lobe Separation Angle) for this particular engine (a 355 SBC with 186 heads and a 10/1 CR gave the widest and best output on a 108 LCA. Spread that angle and watch the torque and HP drop.

                Check out the graph at the end of the text.

                Go too tight and the low speed torque and idle goes down the toilet. But that graph also shows one aspect you need to latch on to. Namely that the output drops off faster if the LCA is too wide than if it is too tight. In other words if the optimum was 108 a 107 LCA would be very nearly as good but a 109 would drop a whole lot more. So if you are going to err then do it on the tight side rather than the wide.

                But I am getting ahead of myself here. Let’s consider duration for a moment as this is the number that goes through everyone mind when they consider the cam size. All these tests I and my crew did actually tells us we should put duration on the back burner so to speak. In reality it is the LCA that dictates how successfully the engine makes torque and the overlap selected that determines where in the RPM range peak torque will occur. Confused??? If you are then don’t worry as this is all out of step with what you have been told by the popular hot rod automotive press for – well forever just about.

                I said we need toi put the duration on the back burner for a while and here’s why. Let’s say that we know from our computations that a 108 LCA is optimum and that 80 degrees of overlap will put peak torque in the rpm range we want with the engine hardware at our disposal. If we know what the LCA is and the overlap there is only one duration figure that fits. With the example two numbers the duration of this (single pattern) cam will be the LCA plus half the overlap and the sum of those two angles times 2 will give you the duration i.e. 2(108 + (80/2))= 296. So we have backed into the duration required Rather than starting with it as an entity which determines the operating rpm range. It does affect it but only by virtue of the combination of the LCA and the overlap. In other words it is more of a result than a determinant.

                OK guys I know there are questions brewing but I am sure that most will be answered by the rest of this article so hold off on such.

                The 128 # part III

                So what is this 128 # good for? In essence it is a way for me to help the unsuspecting engine builder get a cam that is way off. What my you ask would I consider way off/ simple that’s a cam that is anything from 20 to 50 hp and lbs-ft than it could be. Think I’m joking here. Ask yourself just how many cams you have tested and see how that stacks up with what I can bring to bear.

                Let me say something here that you may not have thought of. Let’s say you call your favorite cam company – we’ll call this Company ‘A’. You ask them for a recommendation for your race motor. Even if the guy you talk to is the world’s best all he is going to do is recommend WHAT HIS CAM COMPANY WILL DO FOR YOU. If cam company ‘B’ down the road has a better deal cam company ‘A’ will not tell you to go there and get your cam from them. Cos Cam has thousands of cams/profiles in its library. It recommends what your engine (Not something generically similar) wants and more to the point where to get the nearest to that recommendation regardless of the brand concerned so long as they are capable of top quality workmanship.

                So with all the profiles that all these cam companies have why would we expect that they cannot get within a hair of whats needed. Well there is more to it than just that. Let's use a BB Chevy here as an example. Lets say you have a big inch moderate CR motor with OK heads. This is going to need a cam of about 104 LCA for best torque output over the entire RPM range. You call your favorite cam company and they try to sell you a cam on say 108 for the job. They might even tell you I don’t know what is need as well as they do. What they are not telling you in a number of cases is they cannot grind a cam on a 104 LCA so that is one reason why they do not want you to prder one on such a tight LCA. In other words if they know their cam stuff they are trying to sell you a cam which they know won’t work as well as one from a company that can grind it from their blanks on the desired LCA. If they don't know that 104 is optimal and think a 108 is they are still guilty of selling you a cam that is way off optimum. Not good either way.

                The difference (and believe me I have dynoed a large # of BBC cams ) of a 108 LCA when 104 is optimum is- on say a 572 something like 80 lbs-ft and 50 or so HP. This problem is so pervasive that I have had to literally conduct a search for which companies can do my cams. In an effort to service my readers I have even gone to the trouble of starting to research what I can do to get cost effective blanks done here. (on this subject I want to thank Mike Jones for going out on a limb to help get the wheels in motion to make that happen).

                If you want to throw the advantage of a correct LCA away there is nothing I can do to help out.

                On the other hand if you want to do a fairly accurate estimate of what is needed for the motor you have then just apply (when I get to it – probably in the next installment) the full 128 formula and the correction’s for the CR and possibly good or bad valve seats and you could save yourself a grand or more in dyno time and cam costs.

                Meanwhile I have some more basic rules to apply for getting a good cam spec or at least avoiding a bad one.

                All this business of testing out different LCA and the effect it has on the trapped VE and the way the engine responds to induction pressure waves as measure by port and in-cylinder pressure measurements is very revealing.

                Let’s consider at this point the induction stroke. The optimum timing of the BTDC and the ABDC opening/closing is a question of apportioning what happens before TDC with what happens after BDC. For a given duration there will be an optimal position of the intake center-line that gives the duration just the right proportions before TDC to ABDC opening and closing. The induction stroke itself will always be 180 degrees (or almost so if pin or bore offset is present) .

                When intake port pressure measurements are considered versus the VE based on trapped charge mass then one thing becomes obvious after even just 50 or so various test and that is if the induction event is not optimized in the first half of the induction stroke there is now way on gods earth it can be remedied in the second half. What this means is if the exhaust is working then opening the intake at the wrong time so as to not make use of as much of the l scavenging effect as possible really means paying a price in terms of torque output at any given rpm.

                By the way the induction event of an engine with tuned exhaust is not so dependent on the piston speed but the exhaust pulse. On my 525 BBC mule motor the exhaust pulled on the intake through the combustion chamber with a depression of 8 PSI while the piston at peak velocity at the same test rpm (about 5500) only puled 1 psi on the intake. So worrying about the position of the intake valve in terms of lift at peak piston speed is a minor deal compared to the initial opening.

                OK got to go know it’s dinner time. More by Monday
                DV

                The 128# Part IV

                I think the answer may be obvious but in case it’s not I will pose the question myself. Why did I devote literally thousands of hours testing and evaluating required camshaft characteristics for a given spec of engine? The answer is simple – the so called cam experts were just not delivering so I could not rely on outside advice.

                In practice this is how it works for most of the time. If the cam works then what a great job the cam company did. If it does not work what is Vizard doing here by recommending dud cam specs. If a build fails to produce top results it is my name on the line not the guy who speced out the cam at the cam company.

                Most other tech writers don’t have to worry about this because they are reporting what others do (and so perpetuate an untold number of myths and mistakes). If this business about cam specing did not need to be done do you think I would have spent almost 18 years working on it?? I may not be the smartest guy in the world but also I am not that dumb.

                OK, have got the forgoing off my chest so now let’s look at where we got to technically in the last episode. There I stated that the LCA very much dictates torque output and the overlap the rpm at which that maximum torque value appears. I prioritize making the best torque output as the #1 issue to deal with so let’s look at the factors which dictate achieving valve events that maximize torque.

                Also before going on let me quantify the effect of 2 degrees of LCA difference with the supposedly most important event - that of the intake closure point. 2 degrees change in LCA (for 4 degrees in overlap) has about 400 – 600% greater positive effect on torque than 4 degrees change in intake closure can ever bring about. If you want to disagree with that statement take it up with Mr. SuperFlow 900 or Mr. DTS - not me!

                OK here we go on the subject of LCA. Many (thousands) of dyno tests have shown that as low lift flow increases (the emphasis here is on the word FLOW)for any given cylinder displacement the optimum LCA gets wider and visa versa. This also means that as the displacement under a given cylinder head gets bigger the optimum LCA gets tighter. Here are some practical consequences of this. Many pro engine builders building stroker motors more often than not install a cam for a stroker having a later intake valve closing. Although this usually increases top end power it totally fails to capitalize on the torque potential of the extra displacement . On the other hand by tightening up the LCA to suit the extra displacements need the torque increases almost in proportion to the displacement increase instead of the 1/3 to a ½ seen when the intake closing alone is re-scheduled.

                These are a really handy facts toward selecting a cam - if you have a flow bench, but without one, you’re stuck. But there is an alternative. As it happens most 45 degree 3 angle valve jobs have very similar flow capabilities. At low lift the flow is all about the valve seat job. The port has little to do with things until the valve lift is typically more than is seen by either valve in the overlap period. What this means is, assuming a typical discharge coefficient, we can use intake valve size as a substitute for intake flow. If a graph is plotted out it gives us a curve as per the illustration at the end of this post.. Take a look at the curve on the graph and you will see that it is almost a straight line from 100 degrees along the bottom scale to 112. From this we can say that the LCA = 128 - (CID/# of Cylinders/In Valve dia. in inches x 0.91). Putting some numbers into that we have for say a 355 inch SB Chevy that the required LCA =128- (355/8/2.02 X .91) which equals 108 degrees. So how accurate does that work out to be? Compare it to the graph a couple of posts ago – 108 is virtually spot on and so it will be for any parallel valve pushrod motor such as the SBC or similar (i.e. SB Ford & Chrysler) that has a CR around 10/1 and valve CD in the region of 0.7 (which most 3 angle valve jobs do).

                If the intake valve has better than 0.7 CD average over the first 0.100 to 0.200 valve lift that 128 figure will increase and could go as high as 131 but only if the seats are really trick. If of course they are not and the CD is worse - then the key number could drop as low as 125. But those extreme numbers only crop up one in a while. In probably 90 cases out of 100 the 128 number will apply.
                Not only does this little equation give you a working LCA but also it arms you with some realistic knowledge of what is needed. If your favorite cam company recommends a cam with a significantly different LCA then you need to re-evaluate their cam selection capability. Also give this some thought – how the hell can they recommend an accurate LCA without asking you what the low lift Discharge Co-efficient (CD) is on your heads? The only answer you can come to here is - they can’t!! They are guessing it. Don’t you think a simple formula that gives the LCA to better than 1 degree is a lot better than having the cam company guess it??

                OK not everybody has a 10/1 or so motor. How does the LCA change with the CR? Simple the higher the CR the wider the required LCA needs to be. This is where I get to confront all those claims that COS-Cam cannot possible be right as it predicts cam LCA in the 104 to 107 for most street BB Chevy’s in the 470 to 500 inch range yet we all know that the ProStock guys are using 114 -116. Well the super high CR has a big effect on the optimum LCA. Although there are other lessor influential LCA factors I will leave my explanation of such at just the CR effect.

                Let’s say you have a 540 inch BB Chevy (which requires the 128 number to be substituted with 130.5 to 131 due to the valve angles) with a 10.5/1 CR. If this is the case the combustion chamber volume will be 116 cc. On the other hand the 500 inch ProStock motor will have a combustion chamber volume of just 58 cc. That is half the volume. What this means is the exhaust scavenging action has only half the volume of gases to extra compared to the 540. Right there you can see that, for the 540, more of the opening duration needs to be apportioned to what happens during the overlap period. This means having a tighter LCA so that a greater proportion of the intake duration occurs before TDC. Just so you know where I am coming from here I have tested cams on BB Chevy’s ranging from ProStock to near stock and COS-Cam (which is where the simple 128 rule or 131 in the case of BB Chevy’s came from) works EVERY TIME! The amount of LCA correction for increased CR is typically between 0.5 and 0.7 of a degree spread for every compression number increase.

                Let’s use that 355 (0.030 over bore size) SB Chevy I mentioned earlier as an example. For 10.5/1 it required (with a 2.02 intake valve) a 108 LCA. If the CR goes up to say 15.5/1 (typical for a serious drag race effort) the LCA would need to change (if we use 0.6 degrees as the average correction factor) by 5 x 0.6 = 3 degrees. So our Corrected LCA would be 111 degrees. Up the intake to the more normally used 2.05 or 2.08 and you will see this little computation falls right in line with what we see on the dyno.

                OK there you have it. The 128 # that, as I said in my video for the seminar I did at the University of Northwestern Ohio (where they hold the Engine Master event) it’s no good calling the cam companies because they just don’t know it.

                In case any of you ask if I use this 128 number to generate my cams the answer is NO. I have “COS-Cam which is a 1000 times more powerful. It will even set overlap (and consequently duration) for whatever rpm you want peak power too occur at as well as tell you what the vacuum will be, Once the decision as to what events are needed it will look through a library of cams/profiles and sort (sorts about 10,000 options in about 2 minutes – try that at home) ) the one best suited for the job regardless of who produced them. That way my clients get the best cam not just the best one company has to offer.
                But, in closing here ask yourself why would I calculate my own cams if the cam companies could do it better. If they could then they would make my engine skills look even better to the readers. I have not used a cam companies recommendation for almost 30 years unless constrained too do so by circumstance’s out of the ordinary.

                Well I guess it is now question time. If your questions are answered in my books then I need to let you go to the trouble of reading the answers from such as I have blown a lot of work on this oversize post. If you have a unique question then I will answer it. If you want to go several steps up the ladder toward calculating a very precise cam spec then it will cost because it takes, on average about 75 to 90 minutes. For a COS-Cam calculation go to http://www.waltersengines.com
                DV
                 
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