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Alan_Mac

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Posts posted by Alan_Mac

  1. Posted · Report reply

    Can you tell us which pistons those are?

     

    From what I can tell, it looks like you should have a mile of clearance with .600 valve lift and with up to 2.25" diameter intake valves.

     

    If you do want to to a different cam I suggest you tell us exactly what you want out of the engine so people can make informed suggestions to try and get you close . If you want a custom cam I would have Chris Straub make it . This is nothing against Jay Allen at all and he could also do it but I have dealt with Chris Straub before.

     

    http://www.straubtechnologies.com/

     

     

    Mild, moderate, or fairly nasty idle?

     

    Light to light drag car, freeway flier, or something inbetween?

     

    How far do you want to rev it?

     

    Do you want tons of torque with a 5500 rpm limit or will you sacrifice strong low end power for a 6500 rpm limit etc?

     

    Do you want a "soft" smooth power band or do you want it to suddenly hit fairly hard?

     

    Do you have power brakes, and if so are you willing to sacrifice a little performance mainly in traffic conditions?

     

     

    Probe SRS, -22cc,

    Grand touring, maybe I take it to the drag strip on occasion. 

    Now that I have a manual trans, I am not worried about the idle.  900 RPM is fine, Lumpy, semi nasty

    Red line 6200 +

    Grand touring would lean towards a smooth power curve with allot of area under the curve.  

    No power brakes.  

     

    Alan 

  2. Posted · Report reply

    Thanks for the info . If you were to put a different cam in it like the first one I posted or a similar one, I would keep the carb you have and try it first to see if you like the way it runs as this might save you some money . If you want the best throttle response you can get with a bigger cam I would consider a quick fuel mechanical secondary annular booster 850 carb with the optional slow secondary linkage rod, unfortunately that carb is not cheap.

     

    The first cam I posted is a popular one for 410 and 418 ford strokers etc so it is nothing unusual and would be considered about in the middle for a performance street cam , some people that want much more of a street strip car and fairly nasty/rough idle would use a bigger one.

     

    I would also try your engine with a 1" spacer if you have hood clearance . I think you will find that you will gain some power but you my need a drop down air cleaner for clearance which would put the lid very close to the top of the choke housing which will cost some hp which is one reason why you should not run a choke.

    Barnett; I agree with you suggestion, keep the carb change the cam.  Someone with a similar small 950 carb said his wet flowed at ~830 C. My carb venturi are 1 3/8 dia. and its size is slightly smaller than an 850 venturi.  I am not sure if the P to V clearance will be enough for the voodoo cam intake 231 lift @ .050.  See the attachment here. http://s124.photobucket.com/user/Alan_MacDougall/media/side%20marker%20dimensions/Picture%20099_zpsrwpfaqzb.jpg.html       

  3. Posted · Report reply

    i'm curious to know which 950 you have.  I know there are true 950 cfm carbs and the 950 hp's that are much smaller.  I have the 950hp which has the smaller venturi on mine and it wet flowed 830 cfm (memory) from Pro-Systems.

     

     

     

    Good to know what it wet flowed, I believe my Bigs 950 stage 5 has the smaller venturi,  Both primary and secondary venturi measure 1 3/8 diameter.  They are smaller than an 850 which are both 1 9/16.  So now the carb doesn't seem overly big.  

  4. Posted · Report reply

    Thanks for the cam recommendations,  The first cam seems like a better choice.

     

     The Jay Allen cam was designed for street use, idle ~800 RPM automatic trans with 2300 stall converter, 6500 red line, 350 gears, the engine was in the process of being built but generally the specs were as above except 408W and smaller headers, and a stock RPM intake.  The cam is decent for the street, idles great 850-900 but I expect leaves some power on the table.  The car with the FMX and the 780 VS had an awesome kick in the pants response. When I changed from the FMX to the TKO I also changed to a 950 MS and mostly lost the kick in the pants response.   Here is some feedback from carb manufacturers; 

     

    Holley / QuickFuel;  Recommended a 1) Street-Q Carburetor 750cfm MS or VS 2) SS-Series Carburetor 780cfm VS

     

    Holley CFM calculator: (6400 RPM 830 CFM) (6300 RPM 750 CFM) no choke, MS   

     

    ProSystems: PRO SERIES XC series HP double pumper. Although the specs will vary a little when I am flowing it for the application, your supplied tech sheet follows the carb around the shop during the build.   We'll size it for the exact cfm range when it is on the wet flow bench to match your programs needs.  But it'll probably end up being in the 830-840 REAL cfm range.

      

    I am going to measure my 950 venturi and throttle plate opening for comparison.  As i remember they are smaller than the 850.    

  5. Posted · Report reply

    Barnett, I appreciate you taking the time to respond.  The cam was designed by Jay Allen long ago when my car had a FMX.  Although I am a mechanical engineer and very mechanical, I do not know much about picking a cam.  Link for cam specs here      http://s124.photobucket.com/user/Alan_MacDougall/media/side%20marker%20dimensions/1970%20Mach1%20Strip%20and%20Letter%20Dimensions/cam_zps5vreqlsh.jpg.html ..  Exhaust system is 2.5" magnaflow true X.  FPA full length headers 1 3/4.   I found Pro systems makes a 780 without the choke.   

  7. Posted · Report reply

    what is your exhaust?

     

    who told you to use a 950?

     

    who made that cam?

     

    throw that girly cam in the trash and get a mans cam

     

    780 with NO CHOKE

     

    set your timing CURVE for optimal perf. 

     

    You obviously don't like my car,  950 mistake, I had a 780 before.  The cam is from long ago with an FMX.  FPA 1.75 headers magnaflow exhaust.  Who makes a 780 w/o a choke? 

  8. Posted · Report reply

      I have Bigs (4150) 950 Stage 5 carb and think it is too big. No bog or anything just not as responsive as it should be.  It has been tuned with an innovate.  I am thinking either a Quick Fuel 750 with MS or a 780 with VS. I also want a choke. Here is my application. 

    Street warrior 
    1970 Mustang Mach1 (likely around 3500 lbs with a full tank and me in it)
    6200 RPM Max 
    418W
    AFR 205's
    10.5:1 compression
    Lightweight forged rotating assembly
    Custom roller cam split duration @0,50, intake 219 exhaust 239
    Mildly ported and flow balanced performer RPM intake
    TKO 5 speed 3.27:1 first gear
    3:50 rear 

    Recommendations from carb experts requested!  
    Alan

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  18. Posted · Report reply

    I have Hooker Super Comps 6114 on my car.  I installed the engine with headers and tranny attached.  Took about 2 hours with 3 people, but we got it in.  I can explain how we did it if you like.  I used Remflex gaskets to minimize the chance of header gasket leaks.  As other have said, the top front bolts touch the shock towers.  If you get a chance to buy or look at a copy of Jay Brown's book titled, "The Great FE Intake Comparo," he also shows dyno test results with different manifolds and headers.  It is an excellent book for any FE wrench turner.

     

    The Hooker Super Comp 6114 have outstanding torque which is great for a street car, but other headers had better HP at higher RPMs, so a drag car would like those better.  http://www.jegs.com/i/Hooker/520/6114/10002/-1?gclid=CPfi_Ny159ACFYKHfgodrSMPbw

     

    The FPA headers that others mention have good ground clearance, and are a Tri-Y design.  Stan is the FPA owner, and his shop is close to me.  I've seen his operation, and he has an excellent product.  A friend has some of his headers on his 1958 428 powered Ranchero and loves them.  http://www.fordpowertrain.com/390428triy.htm

     

    Sandersons makes shorty headers, but I have no experience with them https://www.sandersonheaders.com/sanderson-ff393-header-set-fits-ford-fe-engines-in-mustang.html?category_id=76

     

    Hope this helps.

    I love my 351W FPA headers, ground clearance is really great and quality is awesome.  I would give Stan a call about fitment and installation procedure.  

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