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Thread: Development of the Turbo engines

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    Re: Development of the Turbo engines

    Great Thread!!, Thanks for sharing Mr. Davis. Seems this has been a nostalgic month for the old turbo mopars. First I find a four page article about the GLHS in this months muscle car magazine (Hemmings Muscle Machines),
    then there is a thread about our cars on Speedtalk forums http://speedtalk.com/forum/viewtopic.php?f=1&t=49092, and now Mr. Davis shows up with a lot of great info!
    I am very surprised to see the picture of that intake manifold, I did not know anything like that existed when I built mine; Here I thought I had an original idea
    best 1/8 ET-6.16 sec. best 1/8 speed-119.70 Best 1/4 MPH 145.5, Best 1/4 ET 9.65 sec. 8 valve NO NITROUS!!

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    Re: Development of the Turbo engines

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    Re: Development of the Turbo engines

    Quote Originally Posted by stuartshomepc View Post
    well, back then we "borrowed" and AWD unit from a competitor (I think the Audi Quattro?) It was not really a "blessed" program so we had very limited funds. We KNEW from the start that the AWD unit was designed to be mated to an auto trans and could not handle the "shock loads" of a hole shot or "power shift". So we put warning labels on it, and told every driver NOT to do it. It was reserved for executive drives only (but I'd drive it all the time, it cornered great as we had to change the rear suspension and it didn't "plow" into hard corners). Just NO HOLE SHOTS! No power shifts.

    Well, numerous people drove it and one day I had about 6 executives lined up. At Highland park we didn't really have a "test track". Just a straight section if asphalt leading to a warehouse representative of about 1/4 mile and "just enough room" to stop before you nosed into a chain link fence. We all nicknamed it "the drag strip". The best part was once and a while a guy on a fork lift would pull out 1/2 way down, carrying a barrel of fuel or oil. It was "exciting" as we both tried not to hit each other. The facilities department sent out memo's that we could not use it like that, but we did anyway. Finally the fork lift drive learned to drive on the far right side, not down the middle. The problem resolved itself.

    So a few guys drove it, knew the "caveats" and how we would need to do the AWD unit differently "if" we ever produced it. I even had a defined "loop" for them to drive around highland park to go some nice cornering (amongst the burned out houses and decaying city). About the 4th driver decided to do a hole shot. The car jumped about 5 ft, parts came flying out from underneath, and it was done. Without funding I could not fix it. And the interest was starting to grown in a AWD mini van, not a sports car. So the program died. Chrysler was not "real" serious about sports cars beyond simple "tweaks" like the IROC Daytona or GLHS's. We could not compere with the mustangs and Camaro's without LOTS of investment.

    MANY years later (like 16?) another was built with better parts. It was evaluated at the Proving grounds (I think Niel Haneman was the driver, a good guy). While it was a "good car" it was not on par with the competition. It was (in my opinion) a bit unfair as they compared a Daytona against exotic European AWD sports cars. A $15k Daytona vs a $35k European sports car, and gee, it was not as good! It just didn't have enough engine power, nor could we push the engine any harder. So again, the concept was abandoned. Chrysler just didn't see the need for it. The Viper was coming into play, so why tweak a Daytona and dilute Viper sales?
    About what I figured. Actually been considering Audi/VW awd components for a custom build, as I've seen quite a few newer ones handling 800hp (with some aftermarket bits I'm sure). Neat to know that's along the lines of what you guys were playing with back then.

    Do you by chance remember what you did for the rear suspension and diff that made it corner so well? I'm also assuming the drivetrain was still mounted the same up front, with a transfer case off the diff? And hence probably same front suspension?
    Rob M.
    '89 Turbo GTC

    2.5 TIII stroker, 568 w/ OBX and 3.77 FD

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    Re: Development of the Turbo engines

    Since SDAC is in Detroit, maybe Mr. Davis would be interested in a tech session.

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    Re: Development of the Turbo engines

    Quote Originally Posted by Keito View Post
    Since SDAC is in Detroit, maybe Mr. Davis would be interested in a tech session.
    He was on the board of guest speakers for the tech session at SDAC-22. In a departure from the rest of the guest speakers, he told of his drag racing days back then. Many of us considered that to be the highlight of the session.

    Thanks again, Stu!


    Barry
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    Re: Development of the Turbo engines

    Quote Originally Posted by Keito View Post
    Since SDAC is in Detroit, maybe Mr. Davis would be interested in a tech session.
    ** ^^+1 **
    89 Voyager LE, 2.5T2 - rest in peace
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    Re: Development of the Turbo engines

    The only thing good about posting misinformation is that sometimes, the right person sees it and tells the real story.
    Mike Marra
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    Re: Development of the Turbo engines

    I hope he continues to post here. Love reading about the history of these cars.

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    Re: Development of the Turbo engines

    Thread of awesomeness. Great to hear from the source. Thanks you Mr. Davis

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    Re: Development of the Turbo engines

    Quote Originally Posted by sdac guy View Post
    He was on the board of guest speakers for the tech session at SDAC-22. In a departure from the rest of the guest speakers, he told of his drag racing days back then. Many of us considered that to be the highlight of the session.

    Thanks again, Stu!


    Barry
    That whole tech session was phenomenal. Wish I had a tape of it, was very informative
    Thanks Brad S. SDAC National Proud Member SDAC Chicago Proud Member 14 Ram 1500 86 Shelby Charger "Chicago Stock"

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    Re: Development of the Turbo engines

    Quote Originally Posted by 2.216VTurbo View Post
    Not sure if it fits here exactly Stu but it does jive with your 'Transmission being the weak link' synopsis...

    I bought my 87 GLHS new from Anaheim Dodge (about 35 miles from the Putnam Road Whittier Shelby production plant) and soon after befriended a certain 'perfomance parts manager' (that many of us here know) in search of a few more HP. He showed me how to bleed the MAP line a little bit with a small nitrous jet mounted in a little section of 1/4 copper tubing(which we now know was a bad idea for the proper A/F ratio but it was a neat trick 'back then') to achieve 14PSI-ish. One day I drove up to the plant to see said certain PPM to go to lunch or something and while I was waiting outside in the lot, three suits came walking up and commented/asked about my red GLHS and how it got that way. I explained to them what the dealership had told me that they had a truckload of GLHS's and they were slow to sell them all so they painted this one to see if that would move it(it did! I picked it over the other black 87 GLHS they had). So one of the suits says 'pop the hood' and I think I had it up about 3 seconds when one of them pointed to the MAP bleed and asked/said "WHAT IS THAT?? THE TRANSMISSION WON"T HANDLE THAT KID!" Feeling emabarassed and worried about my 2/24 warranty at that point I made some sheepish excuse about the line popping off and that was my fix, closed the hood as soon as possible and made myself scarce...

    Weeks (or years) later that same PPM who was by now a buddy of mine talked about Shelby's testing of the Saines(AKA Chiclett) diff where they positioned a 525 equipped car with one wheel on clean pavement and the other on some sand, dumped the clutch at some stratospheric launch RPM and exploded the trans because of as he described it, 'the load being transfered to the case' from the Saines diff. Knowing what we know now many years later the 525 would have likely grenaded anyway with that type of test

    Thanks for your input here Stu, I suspect you will have no problem getting the TM.com community to help you aquire the parts you seek for your new Daytona Maybe create a 'wish list' of parts that the membership at large can PM you about what they have for you. I know I can personally fill some of that need
    There were several "weak links" in both the 525 and 555 trans. The 2 pinion diff on the 525 was the worst offender, as was the case supporting the diff. The 555 had a better designed diff internally. but with the "bean counters" involved we could not beef of the casting around the diff. We had some aftermarket "girdles" that bolted up to the diff in a vain attempt to help, but it was marginally effective. But for every part we strengthened, another broke. So I'm not surprised at all that "Saines" differential failed the trans case. Over the years, we spent a LOT of time at the local drag strips putting down "oil dry" and sweeping up trans fluid. I blew the trans on my daily driver after being "goated" into a "heads up race". I was the fastest... for the first 15 ft! then, out came the oil dry. And I had no spare trans. That was the last time I raced my car as it was my daily driver.

    The 568 trans was about the best manual we had back then. But it was still not great for the shock loads. Even if it was, the CV joints would blow next. We just never had the "green light" to make a trans from scratch to handle the power/shock loads we put in it. BUT, The Maserati guys did and they sourced two tran's from Getrag that were (in my mind) "pieces of art". They were never used and were disposed of (kinda ). I was not going to use them as they took a very special clutch that would have to be made. I think the pressure plate was 260mm. Since I didn't use them, they made their way to others and I have no clue if anyone actually installed one.

    I once had an engineer from Porsche' come for a "tech exchange" and I took him out for a ride in a stock T II. He thought for what we had to work with it was a reasonable car (but of course he had the "this pales in comparison to a Porsche" attitude). At a stoplight I did a "hole shot" and slammed 2nd and 3rd gear and his eyes were the size of silver dollars. He said "no Porsche' would survive that as it's considered abusive driving!" You can not launch the car like that!

    Then with a smile on his face and in his best English said "Please to perform once again!", and he enjoyed the 2nd one more than the first. He was stunned to hear we do this "for fun" on the streets on the weekend.

    After that I set the emergency brake, put it in 2nd gear and rev'd it to 5000rpm. He looked at me and said "vas ist los" (What is up?) just as I dumped the clutch. The car didn't move and we spent a minute or two "roasting the tires". As we had the windows down, tire smoke filled the car. As he coughed and smiled he said "much fun but this is not done in Europe!". So at least he went away knowing that some of our cars we not "just K-Cars".
    Last edited by stuartshomepc; 03-23-2017 at 05:06 PM.

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    Re: Development of the Turbo engines

    Quote Originally Posted by wowzer View Post
    ** ^^+1 **
    I did one at the SDAC22 that was here in Detroit. Kinda went thru some of the history I've put forth here, but being a "Shelby Dodge" event, and 3 or 4 guys were there to talk of the "legacy of 2.2L Shelby racing". I didn't think I'd have much to add. Ken Soroka (who I've mentored through the years and picked up where I stopped) kinda twisted my arm to come.

    I was stunned at all the guys that wanted to know more about the history, and how to "hot rod" their cars for street use. So I was caught off guard on what to say on the 20 min I had.

    A LOT of people asked me "how do I get more boost?", and I'd roll my eyes as that is NOT the question. The question is "how do I get more total airflow through my system" (air inlet to tail pipe), the then properly fuel it. There is no "one single offending component.

    We all THOUGHT it was the restrictive exhaust manifold, and Dick Winkles had a nice header made up with nice long tubes bent in a"rams horn" orientation to keep the turbo where it was. Tuned headers were KNOWN to help power, so it was built and ran. It hardly added any power. We were kinda stumped. The issue was that the restriction in the turbo upset any "standing waves" in the header, so in reality we just put longer pipes in the system. And the tuning effect seen on a naturally aspirated car was not seen on a turbo. We just came to the conclusion that we had to just "get the exhaust out. But with the "log" exhaust and small ports, there was not much we could do. Sure, Porting helped some as well as some work on the manifold, but the runners really needed to be twice the diameter. (or so we thought).

    So we built a bigger diameter manifold with the turbo in the middle. Sure, it would not package in a car but it was more "optimized" than the production one. Nothin....

    We started playing with camshafts too. 5 degree overlap, 8, 10 ,12 and even 22 degree. The work on naturally aspirated cars, we had them on the shelf so "why not" try them. The high overlap seemed the worst, the lower seemed better. We didn't understand why until we took a "pause" from slapping on and testing parts to be "engineers" and look at the data and form a hypothesis. So, what did we find???

    Well, you are blowing in 10 or 12 psi boost. And during the exhaust stroke the piston is pushing out the exhaust. BUT, right at TDC "IF" you have both valves open, 45psi of exhaust pressure in the turbine and only 12 trying to come it, Which way does the airflow go? high to low right?. So the higher overlap cam left more exhaust (or naturally occurring EGR (ie: no oxygen) and temperature) in the cylinder. So most of us ended up with 0 degree over lap camshafts.

    Then came the "super 60 turbo" with it's lower back-pressure. Great, it helped some. But with no change in the inlet (like the 52mm vs 46mm throttle body, induction system, exhaust, the "bang for the buck" that we expected was not there.

    Some of us started having mandrel bent exhaust systems made, Some improvements to induction systems, and ported of "big valve heads".

    It was not 'till late in the development that I decided that this is an "Airflow machine" and restriction everywhere had to be reduced. So if you guys are still "tweaking", think of it that way.

    So when I had to answer the question of "how do I get more boost", and the guy wanted a 30 second answer, I could not explain "it's an airflow system", optimize it all.

    And cool intake air temps was what the charge air cooler did. We made bigger ones, which gave more power (but induced more turbo lag) and didn't package.

    One guy was dealing with spark knock issues on the Mexican Turbo program where they had to tolerate 85 octane fuel. We started talking about "water injection" "evaporative cooling" and "latent heat of vaporization of the water/alcohol mix in the washer fluid. Yes, I made several up and they worked great letting you run 14psi on 87 octane fuel with no power loss, spark knock or engine damage. But that's a story for another day
    Last edited by stuartshomepc; 03-23-2017 at 03:08 PM.

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    Re: Development of the Turbo engines

    Quote Originally Posted by shmedley View Post
    That whole tech session was phenomenal. Wish I had a tape of it, was very informative
    Well thanks for that nice comment. I had NO IDEA what it was all about and thought it was "All thing Shelby".

    I wish I would have had a clue what I was getting into as I would have organized my thoughts better. I appreciate the feedback. I did get a lot of "thanks" and handshakes and "I got one of your calibrations and finally met you". That was nice. I thought I'd be bored hearing about "Shelby racing" all evening.

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    Re: Development of the Turbo engines

    Quote Originally Posted by Force Fed Mopar View Post
    About what I figured. Actually been considering Audi/VW awd components for a custom build, as I've seen quite a few newer ones handling 800hp (with some aftermarket bits I'm sure). Neat to know that's along the lines of what you guys were playing with back then.

    Do you by chance remember what you did for the rear suspension and diff that made it corner so well? I'm also assuming the drivetrain was still mounted the same up front, with a transfer case off the diff? And hence probably same front suspension?
    Since we were just starting to develop the All Wheel Drive minivan, ,and the rear under-body layout was the same as the Daytona (hell, they were all K-Car based, just stretchered floor-pans) , we had "some" parts, like the rear differential available. We had to make some brackets to hold the rear diff from moving and used some front end wheel hub & bearing and modified driveshafts to make it work. If I had to do it again, it would be much more sophisticated. But in 1983, we didn't know all we know now, and used a LOT of "shade tree mechanics" to put it together.

    But yes, the front end was basically stock with the addition of a transfer case to get a driveshaft to the rear. I honestly don't know what rear diffesential we used, but we borrowed parts from the upcoming AWD mini van and a few European AWD cars with IRS rear suspension. There was a LOT of "Rube Goldberg" engineering in there as we didn't have much money to make the car with. And that was back in 1984, some of those brain cells with the details died off.
    Last edited by stuartshomepc; 03-22-2017 at 05:25 PM.

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    Re: Development of the Turbo engines

    While I was trying to get the best charge air cooler efficiency I built this unit that tucked right into the area next to the head, and where the air cleaner is. It was one of the best functioning units I ever made (so I kept it ) It may find its way onto the new Daytona. I can't seem to upload pictures yet, so follow the links.

    This was a Garret Air-Research core that we welded covers on. It plugged into the turbo T II throttle body. The black rubber likes were an In/Out for a 50/50 water/glycol mix that was pumped to a 2nd A/C condenser that mounted out in front of the radiator. When in boost, a pump made the mixture flow. It had enough cooling capacity to get the charge temperatures down to near ambient. It worked great, but with all the "stuff" in front of the radiator (this cooler, the A/C condenser) we had some troubles keeping the car from overheating after some long runs at full boost at 100 degree ambient temperatures.

    But it shows some of the "out of the box" thinking we were doing at the time. In the end, the :side by side" was the easiest to integrate into a full vehicle system.
    (I don't have permission to upload photos, so here are links to the pics. What does one need to do to get permission to upload pictures?

    https://drive.google.com/open?id=0B3...0ZWT3lYWFBJQUE
    https://drive.google.com/open?id=0B3...0pOMk9oV1JLVVE




    Last edited by stuartshomepc; 03-22-2017 at 06:41 PM.

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    Re: Development of the Turbo engines

    Quote Originally Posted by stuartshomepc View Post
    While I was trying to get the best charge air cooler efficiency I built this unit that tucked right into the area next to the head, and where the air cleaner is. It was one of the best functioning units I ever made (so I kept it ) It may find its way onto the new Daytona. I can't seem to upload pictures yet, so follow the links.

    This was a Garret Air-Research core that we welded covers on. It plugged into the turbo T II throttle body. The black rubber likes were an In/Out for a 50/50 water/glycol mix that was pumped to a 2nd A/C condenser that mounted out in front of the radiator. When in boost, a pump made the mixture flow. It had enough cooling capacity to get the charge temperatures down to near ambient. It worked great, but with all the "stuff" in front of the radiator (this cooler, the A/C condenser) we had some troubles keeping the car from overheating after some long runs at full boost at 100 degree ambient temperatures.

    But it shows some of the "out of the box" thinking we were doing at the time. In the end, the :side by side" was the easiest to integrate into a full vehicle system.
    (I don't have permission to upload photos, so here are links to the pics. What does one need to do to get permission to upload pictures?

    https://drive.google.com/open?id=0B3...0ZWT3lYWFBJQUE
    https://drive.google.com/open?id=0B3...0pOMk9oV1JLVVE




    Nice, I've been running a slightly larger unit set up in the same manner with a 24x7x2 heat exchanger up front in my Lebaron and loved it. Having to move things around now w/ the TIII swap but I plan on staying with water-to-air intercooling, want to add a reservoir this time to help keep it cool longer on back to back drag strip runs.
    Rob M.
    '89 Turbo GTC

    2.5 TIII stroker, 568 w/ OBX and 3.77 FD

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    Re: Development of the Turbo engines

    Quote Originally Posted by stuartshomepc View Post
    While I was trying to get the best charge air cooler efficiency I built this unit that tucked right into the area next to the head, and where the air cleaner is. It was one of the best functioning units I ever made (so I kept it ) It may find its way onto the new Daytona. I can't seem to upload pictures yet, so follow the links.

    This was a Garret Air-Research core that we welded covers on. It plugged into the turbo T II throttle body. The black rubber likes were an In/Out for a 50/50 water/glycol mix that was pumped to a 2nd A/C condenser that mounted out in front of the radiator. When in boost, a pump made the mixture flow. It had enough cooling capacity to get the charge temperatures down to near ambient. It worked great, but with all the "stuff" in front of the radiator (this cooler, the A/C condenser) we had some troubles keeping the car from overheating after some long runs at full boost at 100 degree ambient temperatures.

    But it shows some of the "out of the box" thinking we were doing at the time. In the end, the :side by side" was the easiest to integrate into a full vehicle system.
    (I don't have permission to upload photos, so here are links to the pics. What does one need to do to get permission to upload pictures?

    https://drive.google.com/open?id=0B3...0ZWT3lYWFBJQUE
    https://drive.google.com/open?id=0B3...0pOMk9oV1JLVVE



    man that looks a lot like the setup i had in mind for when i plan on going with the big turbo later on down the road. my line of thinking was to use a air to liquid cooler roughly in place of where the air filter housing would be, use a nice thick core with plenty of flow capability and shortest possible charge pipes between the turbo and throttle body in order to help reduce lag. didnt think of installing the charge air temp sensor directly in the intercooler like that though

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    Re: Development of the Turbo engines

    Quote Originally Posted by crusty shadow View Post
    man that looks a lot like the setup i had in mind for when i plan on going with the big turbo later on down the road. my line of thinking was to use a air to liquid cooler roughly in place of where the air filter housing would be, use a nice thick core with plenty of flow capability and shortest possible charge pipes between the turbo and throttle body in order to help reduce lag. didnt think of installing the charge air temp sensor directly in the intercooler like that though

    My previous setup
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

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    Rob M.
    '89 Turbo GTC

    2.5 TIII stroker, 568 w/ OBX and 3.77 FD

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    Re: Development of the Turbo engines

    Quote Originally Posted by stuartshomepc View Post

    We started playing with camshafts too. 5 degree overlap, 8, 10 ,12 and even 22 degree. The work on naturally aspirated cars, we had them on the shelf so "why not" try them. The high overlap seemed the worst, the lower seemed better. We didn't understand why until we took a "pause" from slapping on and testing parts to be "engineers" and look at the data and form a hypothesis. So, what did we find???

    Well, you ar blowing in 10 or 12 psi boost. And during the exhaust stroke the piston is pushing out the exhaust. BUT, right at TDC "IF" you have both valves open, 45psi of exhaust pressure in the turbine and only 12 trying to come it, Which way does the airflow go? high to low right?. So the higher overlap cam left more exhaust (or naturally occurring EGR and temperature) in the cylinder. So most of us ended up with 0 degree over lap camshafts.
    I discovered this doing back to back cam changes at the dragstrip with the Daytona. Adding pressure taps to the Reliant later in the intake tract and several areas of the exhaust stream and making passes was very illuminating.


    Working on clearing the decks.

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    Re: Development of the Turbo engines

    Quote Originally Posted by stuartshomepc View Post

    We all THOUGHT it was the restrictive exhaust manifold, and Dick Winkles had a nice header made up with nice long tubes bent in a"rams horn" orientation to keep the turbo where it was. Tuned headers were KNOWN to help power, so it was built and ran. It hardly added any power. We were kinda stumped. The issue was that the restriction in the turbo upset any "standing waves" in the header, so in reality we just put longer pipes in the system. And the tuning effect seen on a naturally aspirated car was not seen on a turbo. We just came to the conclusion that we had to just "get the exhaust out. But with the "log" exhaust and small ports, there was not much we could do. Sure, Porting helped some as well as some work on the manifold, but the runners really needed to be twice the diameter. (or so we thought).

    So we built a bigger diameter manifold with the turbo in the middle. Sure, it would not package in a car but it was more "optimized" than the production one. Nothin....

    We started playing with camshafts too. 5 degree overlap, 8, 10 ,12 and even 22 degree. The work on naturally aspirated cars, we had them on the shelf so "why not" try them. The high overlap seemed the worst, the lower seemed better. We didn't understand why until we took a "pause" from slapping on and testing parts to be "engineers" and look at the data and form a hypothesis. So, what did we find???

    Well, you are blowing in 10 or 12 psi boost. And during the exhaust stroke the piston is pushing out the exhaust. BUT, right at TDC "IF" you have both valves open, 45psi of exhaust pressure in the turbine and only 12 trying to come it, Which way does the airflow go? high to low right?. So the higher overlap cam left more exhaust (or naturally occurring EGR and temperature) in the cylinder. So most of us ended up with 0 degree over lap camshafts.
    Very rare to meet someone who has an almost "Mirror" view of things. Where have you been all this time! So much to share, I hope you don't get burnt out responding to every ones Q's.

    So did things develop basically in the order that you put them? ie. Header and large diam. exhaust ports ect first, then big cams came later?

    I only ask this because, while the tube header didn't seem to make much difference with stock cam vs exhaust mani, you may have found that the accelerated exhaust velocity of the header could allow you to run more overlap, and a more N/A profile of cam.

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