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Kevin Shasteen

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About Kevin Shasteen

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  1. Hey everyone, long time no see. I agree w/michael. Get ur car running, then worry about everything else. Whenever someone asks or wants to bench race hp #'s (and yes its always tempting), i always return with another question. And that is, if u know your static comp then tell me what your dynamic comlression is(?). This is usually followed by shrugged shoulders and blank stares. It is important to understand, as a previous posters said, the engine is a complete pkg. Putting 305 heads on may have increased airflow velocity, but has it really increased cfm? Probably not that much. You are still running small intake port heads with a low lift and short duration cam. Hp increases w/out fear of detonation or ping, must always be approached as a complete package. Never hurts to make little changes along the way as the budget allows as long as you understand what affecfs you are making. Do you rember if your pistons were flat tops or dished? If dished then by how much? Remember that hp is torque measured in time. You are putting a low torque engine in a light weight car. You have already fudged the numbers in the torque game already. Dont worry about high hp numbers until you have the budget to build an engine that can handle higher hp. While your project sits i would do what a previous poster suggested. Begin reading about performance engine modifying. Learn what affecfs are altered when certain components, (with different component parameters) are added and how they affect the outcome. Read books at the bookstore, read everything u can in the hybridz archives, ask lots of questions, and get your car running. Its always fun to come back here!!!!!! Kevin, Yea, still an Inliner
  2. Terry, I knew AFR were the best flowing heads on the market; but I was shocked when I checked out the cfm charts for AFR's. Those heads really flow well! I'm betting your engine will put out a peak rpm 520-550 hp at the very least, and according to the rest of your engine package, that 520 is very conservative. The flow numbers of those heads indicate @ 300 cfm after deducting .150" from your cam lobe lift. If the cfm to hp formula has any truth to it, then your engine should be in the 600hp range. I'm thinking the 10.3:1 SCR may hurt the 600 hp potential...., but the 10.3 should be a lot more friendly to the pump gas factor. 1) Is the give or take 550 hp range close to what you were expecting? 2) Once you get it tuned properly are you going to have it dyno'd? I cant wait to hear your comments once the engine-car is up and running. I am sure I dont have to press you for a response after you have test driven it do I? Kevin, (Yea,Still an Inliner)
  3. The concern I had in my past was; does the car have a condernser (can the condenser be moved enough to remove the cam w/out breaking the A/C lines. Do you have to remove the grille, can you do so w/out breaking it. Basically, how much do you have to remove in order to pull the cam out and can you remove those items w/out breaking their plastic retainer ears. W/this engine's position to the front of the car - would the cam be able to come out thru the grille area, core support area w/out hitting any other body parts? If you cant w/out a shaddow of a doubt give a yes to those answers then you are probably better off just pulling the engine. I've done cam swaps w/engines in the car in other vehicles; but never a late model Camaro. Go to your local GM/Chevy dealer or your local speed shop that has their own garage; ask to speak to one of their engine line techs. They should be more than happy to answer your question. I've always had good luck talking to local shops if/when I didnt have an answer to an automotive queston. Kevin, (Yea,Still an Inliner)
  4. BTW, X64v; thanks for the CFM chart for the I6 Datsun head. Zguy, Thanxs for sharing your hp equations; I am an equation junky! I too think the 60hp spread is too much and because of that have refined my approach to the performance engine parameters for a specific level of performance desired. Btw; I do have the normally aspirated hp thing down pretty tight. This is why I was kind've shocked when this 14.7 turbo/supercharger constant jumped out at me; as my exposure to turbo/superchargers is one dimensional (very little knowledge base). That is why I asked for your/others input - knowing there are some pretty smart cookies floating around on Hybridz. FWIW; one variable in helping me to quality the foundation of any performance engine is in qualifying the size (small, medium, large) of the cyilnder heads relative to the cylinder. Once that qualification has been made I can then factor in the relationship to the Combustion Chamber as this is relative to the DCR SCR relationship. I touched on this in an earlier post but didnt really give details, is to convert the Cylinder in the block to a cc measurement. Then take that number and divide it into the Cylinder Head's Intake Port cc. This gives a constant, a relationship if you will between the cylinder head and the the cylinder. Once you have done this a few dozen times you will see a pattern. This is basically the process I follow when analysing any build. You can then take that Cylinder Head/Cylinder constant and categorize it into a certain level of performance. This process works for all levels of performance regardless of pump gas or race gas. The problem I have w/this process is that very few engine build up spec sheets/dyno print outs, found in articles or how to books, hardly ever give the VE% column. I still agree w/you and understand the nuances of subtle modifications in the variables; such as suspension changes, ect. How I see any theoretical is that its purpose is not to give absolutes. Their purpose is to get the end user close to an objective. The equations given as examples were not my equations; they are equations that have been used for a few decades now. In understanding any theoretical, the end user must understand "the spread" will always be at a low, medium, to high potential for success. I would add to your posts that a rule of thumb when choosing to participate in any level of performance competition, regardless if it is full race, street/strip, or hot to mild street engines; is that a certain set of parameters will apply to each category of perfomance. For instance, the Do it yourselfer, will most often build a NA engine in the 1.00 to 1.35 hp/ci range, while most of the Do it youreslfer turbo/supercharger set ups will fall in the 1.35 to 1.65 hp/ci range. So, w/those parameters in mind, if you had access to a couple hundred, complete build spec/dyno sheets; you could evaluate the outcome and come up w/numerous patterns which would help those w/out experience when building their engines in the future. Talkking to a lot of enthusiasts, most dont understand how to qualify power output, much less that their car-engine belongs in a category all together; and when modified - will find itself in transitioning into another category; and so on, and so on. Attempting to transpose the equations, regardless of the variables, to any engine build has become a past time of mine in the past few years. As your vehicle (body, powertrain, suspension, steering, braking) takes on a progressive transition - it will eventually move from one category to another. From talking to many a performance enthusiasts, I have discovered that most enthusiasts doent understand that different levels of performance even exist. IMO, this is where the confusion, relative to understanding the performance engine, begins and ends. As far as the difference in the HP equations going on the low, medium, to high expectations I dont like a 60 hp spread either, but knowing that this is just an equation; I could accept it in the low high ball park spectrum. I dont really use these equations, I only pointed them out to make the point that they use a constant that was derived by empiracal means. I like my approach when it comes to normally apirated engines. Qualify the cyhlinder head to cylinder relationship, as this further qualifies the level of performance that engine will fall in. Once you have qualified that relationship; with that relationship so too will the DCR to SCR relationship and this will further point the end user in the right direction for an intake/exhaust set up. Thanks for the suggestions; this is what I was looking for, real input, real diablogue, along w/real progress. Even if the progress was to come to the conlusion that we dont know what the constant means. I would still like to get my hands on a hundred different non v8 turbo/superchager builds to see if the constant changes w/displacement; and if/why? Kevin,
  5. Zguy, For starters, thanks for your input as I dont consider you or anyone else adding to the conversation as a naysayer - but, I'm not looking for the objectives you have posted as I am very familiar w/the obvious variables involved in engine modeling. As Z8 alluded to, I'm looking for the unknown answers that apparently none of us can offer. I have no problem admitting when I dont know something. that is why I posted this thread hoping to get addt'l input. W/out further data from non V8 tubo/supercharger spec sheets; we have to this point chalked the 14.7 constant up to being a coincidence. But, FWIW; 1) I'm not looking for respect. I'm looking for real responsive answers, not non-responsive answers. I dont care about respect as Math never cares about respect. All that we should care about is the issue at hand on a non bias approach. The question that this thread wanted is to identify, qualify, and offer a repeatable process in other and all turbo/supercharger builds relative to the constant being discussed. You and others are correct in that this constant, by itself is unexplainable. That is why I posted the thread. The fact that this constant by itself is "Not Understood" is why I posted the thread. 2) I didnt bring up the 1/4 mile formula to make the point as to what the equation is made up of. If you think the 1/4 mile formulas are made up of only scientific variables then you would be mistaken. I brought the 1/4 mile formula point up to address the fact that anyone can use those formulas wheather you have a car or dont have a car. The formula is theoretical if you dont have a car. If you dont have a car you can use that formula to obtain theoretical required hp of a theoretical car weighing [x] lbs reaching [x] mph consuming [x] amount of time through the traps. These theoretical #'s give the end user real #'s relative to a potential needed to reach a desired goal..., this is not a bad thing, this is a good thing! My quest to qualify hp in as many ways as I can goes straight to this point, the more data input you have (regardless if you understand it or not) regardless if you do or dont have an actual engine or car; the more data inputs you have the closer to your objective you will actually come w/minimal R&D and less wasted dollars once your project does actually begin. BUT, since you brought up that the 1/4 mile formulas being purely scientific; could you please tell me what the 5.825 and the 234 constants represent for determining: HP = ((Car Weight / (ET/5.825)^3) HP = (mph / 234)^3 x Car Weight Dont try figuring out the constants as I will save you the trouble. Patrick Hale invented these equations, or was the first to admit the equations existed to the public. He claimed the constants were determined from countless hours of empircal numbers crunching. Patrick Hale was not only a drag racer he was also an engineer and a computer programmer. So, if he can admit that the constants either dont mean anything scientific or, at this time are not understood; why cant other constants to other equations also be nothing else than a constant complimenting other real scientific data points? I am personally thankful to Patrick Hale who "fudged" his numbers to give the world the 1/4 mile equations. Another example of "fudged" constants is the overall gearing ratio equation using 335 for a manual trans and 340 for an automatic trans. That equation is: Automatic Trans Overal Gearing Ratio = ((Tire Diameter / 340) x (RPM / MPH)) Manual Trans Overal Gearing Ratio = ((Tire Diameter / 335) x (RPM / MPH)) Larry Shepard created this equation and also admitted that he underwent countless hours of numbers crunching to empirically come up w/the 335 and 340 constants. When a post implies that this thread's constant isnt understood or cant be qualified in itself is not an answer; it is a non-resposive answer. I know the negatives and am not looking for negatives. I am looking for real responsive input. Somtimes science drives the issue and sometimes the little guy working out of their garage or kitchen table drives the issue. The purpose of this thread initially wasnt to disprove or prove the constant. The purpose of this thread was to obtain: a) Why the constant exists What the constant represents In that quest if (apparently none of us can) give real answers to those two issues, then I guess it is implied that the constant is nothing more than a coincidence...until proven otherwise. 3) An idea isnt about posturing one's self to rain on someone's parade. But that is ok as I have a very heavy duty rain coat complimenting my very heavy duty umbrella.., rain away; all that I ask for this thread or any thread is to not posture negatively w/non responsive answers but to try to positively add to the issue at hand. If I (we) dont have a real answer then I (we) need to admit. "I (we) dont know". I dont know what this constant really means; again that is why I posted the thread. 4) Your point that this constant only fits a small set of variables is a good point. For you to say it has no merit is again negative. If I, or anyone, is building an engine w/those small set of paramters; then this constant is a very applicable one w/relative merit. 5) You just made my point for qualifying parameters w/in a specific operating range. If you are using point#5 as an argument to NOT qualify parameters, then there never would be any development of any kind. In order to "develop" someone has to alter the already accepted knowns; otherwise you have zero development. At this point in time w/out any other input, I can accept the fact that this constant does only work for a small set of parameters and w/out further input have accepted the constant as a coincidence. I'm still not going to give up on it; as I will be trying to obtain input from the non V8 turbo/supercharged build spec sheets as those articles present themselves. Thanks for everyone's input. Kevin, (Yea,Still an Inliner)
  6. Zguy, For starters, thanks for your input as I dont consider you or anyone else adding to the conversation as a naysayer - but, I'm not looking for the objectives you have posted as I am very familiar w/the obvious variables involved in engine modeling. As Z8 alluded to, I'm looking for the unknown answers that apparently none of us can offer. I have no problem admitting when I dont know something. that is why I posted this thread hoping to get addt'l input. W/out further data from non V8 tubo/supercharger spec sheets; we have to this point chalked the 14.7 constant up to being a coincidence. But, FWIW; 1) I'm not looking for respect. I'm looking for real responsive answers, not non-responsive answers. I dont care about respect as Math never cares about respect. All that we should care about is the issue at hand on a non bias approach. The question that this thread wanted is to identify, qualify, and offer a repeatable process in other and all turbo/supercharger builds relative to the constant being discussed. You and others are correct in that this constant, by itself is unexplainable. That is why I posted the thread. The fact that this constant by itself is "Not Understood" is why I posted the thread. 2) I didnt bring up the 1/4 mile formula to make the point as to what the equation is made up of. If you think the 1/4 mile formulas are made up of only scientific variables then you would be mistaken. I brought the 1/4 mile formula point up to address the fact that anyone can use those formulas wheather you have a car or dont have a car. The formula is theoretical if you dont have a car. If you dont have a car you can use that formula to obtain theoretical required hp of a theoretical car weighing [x] lbs reaching [x] mph consuming [x] amount of time through the traps. These theoretical #'s give the end user real #'s relative to a potential needed to reach a desired goal..., this is not a bad thing, this is a good thing! My quest to qualify hp in as many ways as I can goes straight to this point, the more data input you have (regardless if you understand it or not) regardless if you do or dont have an actual engine or car; the more data inputs you have the closer to your objective you will actually come w/minimal R&D and less wasted dollars once your project does actually begin. BUT, since you brought up that the 1/4 mile formulas being purely scientific; could you please tell me what the 5.825 and the 234 constants represent for determining: HP = ((Car Weight / (ET/5.825)^3) HP = (mph / 234)^3 x Car Weight Dont try figuring out the constants as I will save you the trouble. Patrick Hale invented these equations, or was the first to admit the equations existed to the public. He claimed the constants were determined from countless hours of empircal numbers crunching. Patrick Hale was not only a drag racer he was also an engineer and a computer programmer. So, if he can admit that the constants either dont mean anything scientific or, at this time are not understood; why cant other constants to other equations also be nothing else than a constant complimenting other real scientific data points? I am personally thankful to Patrick Hale who "fudged" his numbers to give the world the 1/4 mile equations. Another example of "fudged" constants is the overall gearing ratio equation using 335 for a manual trans and 340 for an automatic trans. That equation is: Automatic Trans Overal Gearing Ratio = ((Tire Diameter / 340) x (RPM / MPH)) Manual Trans Overal Gearing Ratio = ((Tire Diameter / 335) x (RPM / MPH)) Larry Shepard created this equation and also admitted that he underwent countless hours of numbers crunching to empirically come up w/the 335 and 340 constants. When a post implies that this thread's constant isnt understood or cant be qualified in itself is not an answer; it is a non-resposive answer. I know the negatives and am not looking for negatives. I am looking for real responsive input. Somtimes science drives the issue and sometimes the little guy working out of their garage or kitchen table drives the issue. The purpose of this thread initially wasnt to disprove or prove the constant. The purpose of this thread was to obtain: a) Why the constant exists What the constant represents In that quest if (apparently none of us can) give real answers to those two issues, then I guess it is implied that the constant is nothing more than a coincidence...until proven otherwise. 3) An idea isnt about posturing one's self to rain on someone's parade. But that is ok as I have a very heavy duty rain coat complimenting my very heavy duty umbrella.., rain away; all that I ask for this thread or any thread is to not posture negatively w/non responsive answers but to try to positively add to the issue at hand. If I (we) dont have a real answer then I (we) need to admit. "I (we) dont know". I dont know what this constant really means; again that is why I posted the thread. 4) Your point that this constant only fits a small set of variables is a good point. For you to say it has no merit is again negative. If I, or anyone, is building an engine w/those small set of paramters; then this constant is a very applicable one w/relative merit. 5) You just made my point for qualifying parameters w/in a specific operating range. If you are using point#5 as an argument to NOT qualify parameters, then there never would be any development of any kind. In order to "develop" someone has to alter the already accepted knowns; otherwise you have zero development. At this point in time w/out any other input, I can accept the fact that this constant does only work for a small set of parameters and w/out further input have accepted the constant as a coincidence. I'm still not going to give up on it; as I will be trying to obtain input from the non V8 turbo/supercharged build spec sheets as those articles present themselves. Thanks for everyone's input. Kevin, (Yea,Still an Inliner)
  7. Terry, I believe you made the right choice on your heads and will be very pleased. I know you like the high rpm rev'g engine - so more curiosity; what cam profile did you choose and which SCR did you decide on? Kevin, (Yea,Still an Inliner)
  8. A few years ago I made my own Tq/Hp loss due to Aero Drag Calculator and Turbo calculator. With your gearing and the assumed .45 to .49 Cg and 7psi boost; I think your engine was putting out more than 180 hp. My Aero Drag calc does not take turbo/supercharged psi into consideration as it merely takes the Cg, Frontal Area, Gearing, HP, Tires, MPH into consideration but the Turbo Calc obviously takes boost into consideration. The Aero Drag calculator indicates 180 hp at that rpm w/your gearing would be experiencing a -3 to -17hp depending on which Cg of .45 or Cg of .49 you went with. My Turbo Calc uses Corky Bells calculations from his book. His assumption of a low to high hp puts your engine in the 165 - 245 hp range. Since you said you had a little more throttle left at 141 mph, I'm betting your engine was in the 200 hp to 200+ range. I'm betting your engine was making more than you thought it was. When you hit the 141 mph mark did it feel like you could've grabbed 5th w/out loosing speed (or did you have a few other things to worry about - like staying on the road)? Did the engine feel like it had a little more to offer? Its late, I gotta get some sleep. Talk to ya in the morning. Kevin, (Yea,Still an Inliner)
  9. Terry, Thanks for the post. Which cylinder heads did you decide to go w/for your stroker? Kevin, (Yea,Still an Inliner)
  10. What trans, differential gears, and tire size were you using at that time? Kevin, (Yea,Still an Inliner)
  11. Its okay to be critical. I am probably the biggest critic of myself. My agenda? About 7 years ago I began researching the engine behavior to an nth degree. Since then, crunching #'s to identify patterns has become a past time for me if/when I have the time. When you have crunched as many numbers as I have (I dont like the way that sounds because it sounds haughty - and I'm not haughty in any way), you will actually begin to see patterns. I have played w/the turbo math and like the idea of turbocharging an engine - yet have never had the time to actually turbo an engine. All my hot rodding was years ago w/the muscle cars; normally aspirated at that. When I saw the coincidence, as you put it, while crunching #'s, it kind've took me by surprise. Knowing that any IC engine is an air pump and that all components that when factored into the next component it interacts with will create a ratio or create a value, which ever vernacular you prefer; and that this value can then be quantified to determine components as mild, moderate, or maximum..., then regardless of displacement the coincidence should surface on any turbo/supercharge engine. If one accepts the assumption that any engine is prepped or optimized for street/strip use; then the only caveat to this coicidence would be in not knowing VE% and not knowing if/how much the constant (the 14.7 coincidence) changes w/variances in displacements. What I wanted to see, if possible, was any turbo/supercharger spec build to find any meaning at all to this concidence. What am I trying to accomplish? Nothing, maybe nothing more than passing time! BTW, this process (not including turbo/supercharged engines) works very well for the normally aspirated engines running in the 1.00 to 1.35 hp per cubic inches regardless of displacement. Once you get beyond the 1.35 normally aspirated hp per cubic inch, there is more going on than just airflow; which comprimises the close tolerance the cfm hp formula brings to the table. Crunching #'s of any engine build article is kind've a facination of mine. I like to attempt to prove to anyone willing to listen that engine performance is mostly predictable; if you understand how to qualify the variables involved. I was not looking for this coincidence when I came across it. This coincidence that this thread concentrated on was nothing more than a numbers crunching accident that took me by surprise; and I wanted others to offer their input before I moved on. It appears the data on the turbo/supercharged non v8 engines are not as easily obtained as v8 performance is. With that in mind - apparently this thread has run its course. Unless someone has something else to add I think we have beat this dead horse as much as we can. Thanks for humoring me everbody. x64v, Does anyone have a cfm chart for the Datsun I6 cylinder heads? I have searched the net over and can not find them for the life of me. You would've thought someone by now would have posted a cfm chart for these engines. Kevin, (Yea,Still an Inliner)
  12. x64v, how did you go about guessing at the hp of your turbo L24? Why do I need the cfm chart? My need for the cfm chart is the same reason any pro engine builder will utilize the cfm chart. Engine builders will use that data to prove their required paratmeters [on paper] before they build that engine. I always like to ge a cfm head chart of any engine build as it futher proves the cfm hp formula does work (not including this anomaly), in the real world if you know how to use it. This process takes the full cam lift x rocker ratio to obtian full valve lift. With that full valve lift the process then deducts .125" to .150" from the full valve lift; and whatever that value is - we can then go to the cfm chart and obtain the cfm required (according to the cfm hp formula) to determine what the theoretical cfm is required to obtain that hp output. For turbo/supercharger engines the full valve lift minus .100". The cfm to full valve lift minus the appropriate .125" to .150" for normally aspirated engines to .100" for turbo/supercharger engins is the cornerstone of the process. That is why I need the cfm charts for any cylinder head as well as the cam profile specs; as those two are interacting. I know this anomaly/coincedence (whatever you want to call it) has no real sicence to it (as we know at this time) I just find it interesting. You gotta admit it raises an eye brow! Believe me, I am very methodical when I examine an engine build. I understand the pressure ratio math. I still find this anomaly interesting and when I come across something that has repeatable resultes (even if it only occurs on v8's at this time), my mind does not let it go until I am satisfied that I have approached the oddity from every possible angle. I would really like to get as many non v8 turbo/supercharger engine build articles, in my hands, to analyse as possible. I've tried reading the non American V8 engine mags for data but they never give parameters for their cylinder heads and rarely will they give all the spec's for their cams they use; I have a good idea of what their cam specs are. I would really like to know their cylinder head parameters. BTW: since the VW issue came up, I bought a Performance VW book in the early 90's where KRE was claiming type 1 VW engines putting out an easy 250+ hp engines w/a turbo on mild boost, 400+ hp on that same engine w/more boost. In that same book at that time KRE had a methonal burning type 1 VW enigne putting out 600+hp using a turbo. Kre says prior to the 70's you were lucky to get max 180hp. With the advent of cylinder head tech the 180 hp engine is an easy one. Of course they never gave a dnyo in the older book, never gave a cfm chart for their cyl heads: they did give cam specs for the 250 and 400 engines. KRE since then has been know for 1000+ hp for full race type 1 VW engines. Can anyone point me in the right direction for turbo/supercharger articles that offer as complete as possible data regarding engine parameters for a non V8 engine? Kevin, (Yea,Still an Inliner)
  13. Z8, I would say yes, the articles anyone presents needs to be a turbo/supercharged engine for us to further prove/disprove this anomaly. Along the lines of x64v's following questions, I would more than welcome non V8 examples in an attempt to see if the 14.7 constant changes w/engine displacement. I wouldnt say horrible assumption.., I would say "Not yet qualified" assumption. Hence the purpose for this thread. I would agree w/you in that the only articles I have are from American V8's; as the European crowd is horrible in not giving complete parameters in their magazines and they, the Euro mfg's seem to be leading the way in regards to turbo engines; yet if they are leading the way then why are they so non-revealing when it comes to their engine paramters in their performance mags. That is one element I really appreciate about the American magazines - they are about the most complete articles of all others. In an attempt to qualify the anomaly's process relative to your VW and L24 engines; my first question would be: 1) What does the cfm charts for both the L24 head indicate and What does the cfm chart for the VW head indicate 2) Secondly, if you were going to use a turbo on the L24 or the VW; then you would want to utilize a cam lift whose max lift was .100" higher than the cylinder heads cfm required to make that hp per the cfm hp equation. If someone can come up w/a cylinder head chart for the L24 or VW engine I believe this would be an excellant example to further qualify this anomaly. Kevin, (Yea,Still an Inliner)
  14. Z8, looking foward to your ideas. Thank you kinked chrome. I never even thought of it that way; but I do believe you have nailed it, which is why I posted the thread. If you get more brains attacking an idea it is merely a matter of time before someone comes up w/the solution. Why, try to get as close to a HP rating as possible? Have you not ever read an article where the authors of the article and the builders of that engine state before they put the engine on the dyno that said engine should make [x] amount of hp; and once the engine is put on the dyno they are w/in 10 to 30hp of their guestimate? I personally like the idea of knowing, within as close a proximation as possible, what an engine will make prior to that engine being put together. The purpose is to make sure I dont, and to make sure any other performance engine enthusiast doesnt, OVER BUILD/OVER CAM their engines. I ran into a guy (never met him before) who had built a twin turbo SBC engine. He had it entirely build, spent a lot of time and money; yet couldnt get one of the turbos to spool. He said the cam company couldnt give him any answers, his cylinder head company couldnt help him and none of his friends could help him. He told me his tt engine has been sitting now for about 6 months and he was thinking about pulling it and putting in a BBC. I asked him what his cam specs were and in two minutes I suggested his cam had to much overlap in it. He told me Comp Cams had sold him a cam according to his wishes. I told him I dont know what he asked Comp Cams for and I dont know what Cam they think they sold him - but, if his cam has as much overlap in it as he says it does....his cam is the problem. He told me that, if the cam were his problem, that I had solved his problem in two minutes that no one else has in the past 6 months. He had even called the turbo company and cam company multiple times trying to figure out why his one turbo would not spool up. He came by my work a few weeks ago and told me that Comp Cams had on their computer sold him a turbo cam, yet somehow someone had grabbed the wrong cam in the warehouse and sold him the wrong cam by mistake. Comp Cams gave him the right "Turbo Cam" with the correct overlap in it. Now he has a TT SBC that kicks but. Why couldnt anyone else help this guy? Why did it have to be me? I dont know - but I like the idea in knowning that my efforts helped some guy out there that was about to give up on his tt engine becuase of an accident at the cam company. Why do we spend so much time staring at our computers utilizing an engine simulator trying to decide which combination is best. Doesnt anyone realize that these simulators are based on equations? I like the idea of knowing what an engine will make before that engine is put together; that is just me and so when I read an mag that has a well written article in it - I buy that article and put it thru a lot of scrutiny in an attempt to further my understanding. This scrutiny adds to my past knowlege base. Anyway, that is why I go to such exstremes. This anomaly being discussed on this thread is identical to the 1/4 mile equations where if you have a time slip of any car going thru the 1/4 mile trap, you also will have the speed of the car, get the car weighed w/the driver in it and then you can solve for the amount of RWHP needed to make that 1/4 mile trip. With any equation you can transpose those variable if one variable is missing and all others obtained. With that 1/4 mile formula in mind - the end answer will give you RWHP. Then you can add the usual assumed 15% loss of power due to drivetrain inefficiencies to obtain FWHP. Now that you have the FWHP you pretty much know how your engine stands performance wise; yet this 1/4 mile formula in no way dictates which car should be used, it in no way dictates which engine/trans/cam/heads/suspension...or anything else should be used. If you didnt even have a car you could still utilize the 1/4 mile equations to know how much FWHP is needed to get a theoretical car down the 1/4 mile if you had car weight of [x] and wanted to go thru the traps at a speed of [x] you could determine how much FWHP is requred of your engine (you have not yet built) in order to perform at that level. So, if you dont have a car yet you can use the 1/4 mile formula: what good is it? By itself, nothing; yet it is good in giving the end user ideas of how to get close to their desired objective. From there good ole research and development takes over. I believe this anomaly - if it plays out falls into this same category. For those of you who think the numbers are fudged; I do have a process for normally aspirated engine analysis; and I can work it forwards or backwards depending on which variables are known or not known. You dont have to know everything in order to come up w/reall #'s. You need to know a lot, w/common sense; but the mfg's take care of most of the intangibles. I always try to concentrate on three relationships: 1) DCR to SCR relationship 2) Peak Power to Displacement relationship 3) Peak Power RPMs This is how I approach every well written performance article. The very first thing I do is determine the relationship between cylinder heads and the cylinder. This relationship gives me a constant that after you have done this a few hundred times you will begin to see patterns. The qualifier you will begin to identify by doing this will determine if the cyl.heads are mild, medium, or maximum for the level of performance you have chosen. The second thing I do is determine the overlap of the camshaft. Anyone who has been researching engines will recognize the cam overlap chart that has been around for years. This further indicates patterns; of which further allows the researcher to understand the category of performance that engine will fall. The third thing I do is locate a cylinder head CFM chart of the cylinder head(s) used in the article. Once I have that CFM chart I then determine what cfm is required to make the hp the dyno dictates. Again, after you have done this a few hundred times you will begin to see patterns and these patterns will allow you to know what an engine will put out before you actually ever look at the dyno. The one floating variable that can not be known is the volumetric efficiency of that engine. For most do it yourselfers, it can be assumed as most do it yourselfers build a normally aspirated engine in the 1.05 to 1.35 hp per cu.in. and in the 1.45 to 1.65hp per cu.in. for turbo/supercharged engines. Yet when a master engine builder puts together an engine and has utilized all of ther resources - the VE% can not be assumed as they know things you and I will never know. So, for the average engine build you and I read in any performance mag or how to build engine books, the pattern I have seen regarding the: CFM x .256 x #cyl's = HP formula, is this. For a [normally aspirated] engine you CAN NOT use the maximum valve lift number. You have to deduct .125" to .150" from the full valve lift number and take the CFM from the cylinder head chart that matches the full lift minus 125-150"; and input that valve into the hp formula. VE% not withstanding, you will be within 10 to 35hp of what your engine actually makes about 95% of the time. Other patterns I have noticed regarding the VE%, relative to the CFM x .256 x #cyl's = HP formula is this. If your normally aspirated engine is utilizing an 8.5:1 to 9.25:1 SCR, then you can assume an .85 VE%. If your normally aspirated engine is utilizing a 9.5:1 to 10.0:1 SCR then you can assume a .90 to .95 VE%. If your normally aspirated engine is utilizing a 10.5:1 to 11.0:1 SCR then you can safely assume a .95 to 1.00 VE%...., all this is assuming your cylinder head to cylinder relationship is proper (with all other components being properly fitted...even in the mag articles sometimes the components are mismatched) Vizard thru all of his books will say, "Providing the other components are properly matched"..., so if he can assume properly matched components - then so can we when making calc's for a paper engine not yet built. Regarding the turbo/supercharged engines, the valve lift per cfm chart number needed to get close to actual output is usually .100" less than full valve lift...but, my exposure to a turbo/supercharged engine is limited; which is again why I posted this thread. Other patterns I have notices is the DCR to SCR relationship regarding performance engines. This relationship further ties into the cam overlap to engine-car intent relationship, which further falls into the cylinder head to cylinder relationship. DCR will usually be in the 8.25:1 to 8.5:1 for engines utilizing an IVC of 55 to 65 degrees ABDC which allows somewhere in the 80% to 85% cylinder filling once that intake valve has closed. DCR will usually be in the 7.75:1 to 8.0:1 for engines utilizing an IVC in the 70 to 75 degrees ABDC which allows somewhere in the 70% to 75% cylinder filling once the intake valve has closed. DCR will usually be in the 7.25:1 to 7.5:1 for engines utilizing an IVC in the 75 to 80 degrees ABDC which allows somewhere in the 70% to 65% cylinder filling once that intake valve has closed. With this you can utilize the DCR to decide which optimum SCR is required to overcome the harmful side affects of the cam overlap being used. All this can be confirmed through the DCR^1.2 x Atmospheric Pressure = BMEP equation You can utilize this equation to confirm what cam IVC spec is required if you want a particular BMEP relative to Atmo your engine will be operating in. And if you know BMEP then you can further qualify things thru the, PLAN / 33,000 = HP, or the IMEP - FMEP = BMEP eqution. How many ways one decides to qualify hp depends on that persons personal understanding of hp. I have a process - many may not understand it, but I do have a process that works and is repeatable. If I ever run into a person who has desiged software for an engine simulator, my first question will be to have them show me how they have calculated IMEP. I know how to calculate BMEP and I can calculate FMEP..., but I can not seem to come up w/anyone who can show me how to calculate IMEP. The IMEP calc's are very proprietary. Again, how one decides to qualify HP depends on their personal understanding of hp. I believe I am well read on most subjects and I have built a number of engines in my past so I have experience in that dept as well. I would not call myself an expert as I am not an engineer nor do I have access to the indicators and propieriatry equations those engineers have access to; but I can hold my own .02c's worth when needed. The process is an equation that can be transposed, extrapolated, and done forward or in reverse; as long as you understand the equations. Again, thanks Kinked Chrome for your input. I think your comments are a bullzeye. This was an anomaly that by itself means nothing; but I still like it. Kevin, (Yea,Still an Inliner)
  15. I have to agree about the pictures thing, if you have them we need them; lots of them! Kevin, (Yea,Still an Inliner)
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