400 hp, 500 tq .030 over 401?

Discussion in ''Da Nailhead' started by 401Riviera, Oct 15, 2012.

  1. 401Riviera

    401Riviera Well-Known Member

    Okay i will leave the heat in the mainifold. My Engine builder got me the hook up on MSD stuff, so i got a pro-billet Nailhead distributor now.:grin:
     
  2. CameoInvicta

    CameoInvicta Well-Known Member

    That will come in handy trying to dial the Thumpr in. It likes a lot of initial, but you can't end up with more than 34 or 36* total. I think I finally settled in at 21* initial, 35* total, all in by 2200 or 2300rpms. Your also going to have to source a B28 vacuum advance can if you want the vacuum advance to still be operational, since the Thumpr produces little vacuum at idle. The MSD might have an adjustable vac advance unit but I'm not sure.
     
  3. 401Riviera

    401Riviera Well-Known Member

    I'll talk to my engine builder about everything. He'll know what i need to do with the vacuum advance and everything.
     
  4. gsgtx

    gsgtx Silver Level contributor

    good luck with your nailhead :TU:
     
  5. 401Riviera

    401Riviera Well-Known Member

    Thanks guys! I just got the block resurfaced, Nice and clean deck now. Resurfacing the heads next week. Checking the main clearances and then assembling the short block with the cam and timing chain.
     
  6. 66larkgs

    66larkgs paul 66gs turbo nailhead

    I run a msd dist, coil and 6 btm box. Love it but isn't cheap. Gd luck with your build
     
  7. gsgtx

    gsgtx Silver Level contributor

    just wanted to add that a fresh air scoop really cools the intake charge, where heat to the intake matters more. i can do one run it will be fine and then a second run right after it might stumble because the cool air and fuel cools the intake. i ran both heater hoses under the intake for some heat when i had the heat blocked off which helps.it seems with ethel fuel you need more heat. the local gas stations came back with no ethel high test unleaded fuel now and it seems like you can get away with less heat. also if its 60* or warmer theres no problems.
     
  8. mr62buick

    mr62buick Well-Known Member

    You want to see your future... go to youtube and look up "1962 blown buick nailhead" That is a 401 bored to a 438, 6:71 Gale Plummer supercharger and a Don Hampton gears/blower custom manifold. Just take a look!

    Rebuilt 438 with ALOT of internal goodies $1500 (I really know how to hunt for parts & people paying off favors)
    Blower manifold, gears, belt, $2000
    Blower with carbs and scoop (used) $2000
    Furds, Chebbies, and other car owners faces dropping in awe and old car guys smiling..... PRICELESS!
    :cool:
     
  9. doc

    doc Well-Known Member

    Works for me.... but a guy better have some forged pistons in that puppy or the huffer will take it apart for you....:Brow:
     
  10. nailheadnut

    nailheadnut Riviera addict

    A 0.030 over 401 will yield about 413 cubes. To get to 438, wouldn't that engine have to have a stroker crank in it as well? However, a 425 with an addition 13 cubes would give you a 438. In a subsequent video of him driving it, he mentions that the engine is from a '65.

    Ed
     
  11. telriv

    telriv Founders Club Member

    A 401+.030" = 406.8 CID Formula bore-4.1875" x bore 4.1875" x stroke 3.64" x .7854 x 8= 406.8 C.I.D. For every .010" overbore on most V-8 engines equals about 2 cubes.


    Tom T.
     
  12. nailheadnut

    nailheadnut Riviera addict

    My OOF DU. The numbers I quoted were for a 0.060" increase in the bores. A 0.060 over 401 yields ~ 412 cubic inches. A 0.060" over 425 yields ~ 438 cubic inches. That guy is running pretty thin cylinder walls AND puffing it.

    Tom,

    As a math teacher, I always taught this formula to calculate the volume of a cylinder: Pi x radius squared x height. For an engine you'd mulitply that time the number of cylinders, in our case eight.

    So for a 425 bored 0.060" over you'd have: 4.3725 / 2 to find the raduis = 2.18625. Square that = 4.779689063 (10 digit display on my calculator.) Times Pi = 15.01583605. Times the height (stroke) of 3.64 = 54.65764322. That's for one cylinder. Multiply that times eight cylinders = 437.2611458 cubic inches.

    When I do it my way, a 0.030" over 401 yields 405.46, you got 406.8.

    I'm interested in your formula. You squared the bore (diameter not radius,) then multiplied that by the stroke, then multiplied everything by .7854, then times the number of cylinders. What is .7854? Is your formula something engineers use to compensate for something else that I'm not considering?

    Thanks Ed.

    ---------- Post added at 11:44 AM ---------- Previous post was at 11:13 AM ----------

    Tom,

    I figured it out. .7854 is Pi divided by 4.

    Using it and the diameter squared gives the same results as squaring the radius.

    If the diameter were 10 and you squared it you'd get 100. Divide 100 by 4 and you get 25

    If the radius (half the diameter) were 5 and you squared it ( 5 x 5 ) you get 25.

    Same song, different verse.

    Depending on how accurate you want to be, .7854 is Pi divided by 4 rounded to ten-thousandths.

    Pi is an irrational number so Pi divided by 4 will be one as well. On my calcuator, Pi divided by 4 = .785398163.
    At what point will 0.000001837 start making a difference? :Smarty:
     
  13. telriv

    telriv Founders Club Member

    That's the formula I have seen in MANY books. For me it's the easiest to remember. As far as all the other formula's you have posted, are over my head. As you stated, just diff. ways to come out with & accomplish basically the same thing.
    I try to use the KISS principal whenever possible.

    Tom T.
     
  14. nailheadnut

    nailheadnut Riviera addict

    Tom,

    The one thing about the one formula that easier is that you don't have to remember the .7584 or .7854 or .7485 or what ever the heck it was. All you have to know is the diameter (bore) and the height (height.) All the rest is part of my calculator's keyboard. There's a Pi key, a "squared" key, and a multiplication key. On the other hand, if you use your formula enough, that constant (.7854) will become a part of you and you won't need a Pi key or a "squared" key.

    The odd thing for me is that for as many years as I've taught math, this is the first time I've ever seen that constant as part of an area formula (you get volume when you multiply by the stroke.) When I googled it, it seems that the formula with the constant is the only one engineers use.

    Ed
     
  15. telriv

    telriv Founders Club Member

    I wouldn't call myself an engineer by any means. Although I have MANY thoughts in my head about what could possibly be if such & such are done. Then I try & go about figuring it all out. Then the questions come up of why/why not??? Like air is just like water or electricity, it will take the easiest path. Usually that means a boost in performance & the resulting better volumetric effienceiy which relates to better fuel economy, if you can keep your foot out of it.


    Tom T.
     
  16. John Codman

    John Codman Platinum Level Contributor

    I'm curious as to how things are going. Someone touched on the Dynaflow. I love driving a car with a Dynaflow, but it's not as efficient as a THM 400 (which is not as efficient as a 700R4). If the engine has a '63 crank, there's some work involved to get it to bolt to a THM400. If you decide to use an OD unit, an adapter will be required, as all GM OD transmissions use a Chevy bolt pattern. Brandtsen's makes adapters to bolt any Nailhead to a Chevy-pattern transmission, so a '63 crank is not a problem in this event. BTW: If the Dynaflow is not going to be used and is good, it probably has some value.
     
  17. snake

    snake Well-Known Member

    Pi r 2 is the constant for .785 , if you had a one foot square and cut the corners off making it round thats what .785 is a round cylinder, water math taught me this. That's how you would find how much water is in a pipe.
     
  18. 401Riviera

    401Riviera Well-Known Member

    I love the math lesson haha :laugh::grin:. I have already gotten an adapter and the correct spacers for the flywheel and had everything balanced, the mains will be done Wednesday and the shortblock should be together the same day. Really looking forward to it.:grin: I'm also trying to sell the dynaflow, a guy offered me 150 for the trans with all the linkage and flywheel etc. I bought a rebuild kit for it which is where i'm losing all the money. Rebuild kit was $230. Its gonna cost me about $800, give or take a few hundred, to complete the St400 swap (driveshafts, linkage, rebuild, converter, etc.). People keep asking me "why the trans swap? why not keep the dynaflow???" Its simple, i'm only 18 but i know the st400 is a better trans, it'll be better for cruising, better for performance and more fun. The car would put me in the seat with the 401 with sticking valves and blow-by in two cylinders with the dynaflow. So it'll be almost a completely different car with the fresh nailhead with more power, fresh st400 with a converter, manual valve body and a shift kit. I'm pretty interested in how this will turn out. Still lots of work to do on the car. But it should be done in a few months.
     
  19. CameoInvicta

    CameoInvicta Well-Known Member

    Curious what spacers you are referring to for the flexplate? Once you remove the raised lip on the crank, the flexplate should just bolt on. And of course you'll need the crank bushing adapter to hold the snout of the torque converter, but it should fit together perfectly.
     
  20. doc

    doc Well-Known Member

    I did not remove the lip off the crank.... took the flex plate to a machine shop and had them to open the center hole up enough to work with the dyna crank flange...i raced the thing hard for several years and never had a problem with it....
     

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