bbc, 8-71

Discussion in 'PSI Superchargers Tech Questions' started by vht, Apr 21, 2017.

  1. vht

    vht Member

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    Building a engine for a street and strip gasser, how would a externally balanced BBC hold up with a Dyers 8-71 street set up? Low boost, pump gas, race fuel at the strip, also was going to use a Devils Own water injection with a 50/50 mix. On 12 or so lbs of boost, what would you suggest on a short block? I have a nice 2 bolt main fresh 40 over block, with ARP studs, would this hold up? I will update some stuff later, but for now I just want to get something going that will run decent and be fun to mess with. Been awhile and I miss making some passes.
     
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  2. gordon tarbell

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    Use about 10% underdrive on the 8-71 and assuming around 468 cu in BBC this will put you around 9 psi in manifold. As long as you don't buzz it up past 6500rpm, don't let it be lean , don't let total ign lead be more that 28-30*. keep water temp below 180* ,high flow water pump and big radiator, Idle speed not below 850 . Set initial lead around 16* due to low static compression nescessary (8.5-9.0:1) . As far as cam timing keep duration between 230 and 240 @.050 and LSA 110-114* . There are dozens and dozens of combos that will fill the requirements . Make sure your fuel system (From pump to carbs can flow the volume of fuel needed .)
     
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  3. vht

    vht Member

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    What electric fuel pump would you suggest? I'm running 1/2 in line from the cell, return style regulator with a 1/2 return line.
     
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  4. vht

    vht Member

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    Also can I run just the crank hub and not worry about a balancer?
     
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  5. gordon tarbell

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    You don't need to worry about running a harmonic dampner / crank balancer . The blower being driven direct off the crank is a good dampner . Make sure you have your rotating assembly well balanced and things will be happy on that front. I would suggest Calling Dyers for fuel pump suggestions, I have not kept up with who builds what electric pump. I have not messed with blown gas in a coons age or three. This site is geared toward blown Alcohol using mechanical fuel inj. as is my memory. Take your time and do your research . Might want to call one or two of the carburator specialty shops and discuss your fueling requirements. Take baby steps and have fun learning. Also try to get copy of Canters plug reading info for gas setups. He is a regular on here. You might find Dave koehler from this site very informative also.
     
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  6. vht

    vht Member

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    Thanks for the info, if this was strip only, it'd be mech injection on alky. I run mech inj on my dragsters for over 20 years. I can build the carbs for a blower set up, I can't say I like carbs, but I can't afford the new $4500 dollar efi set ups. Mech injection was so much easier.
     
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