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Technical FlatCad on da Dyno

Discussion in 'Traditional Hot Rods' started by roseville carl, Apr 9, 2014.

  1. Hey Gang:

    Just got back last night from NorCal and working with the FlatCad crew - getting our engine together, tuned and tested for El Mirage and Bonneville. It was a lot of work to put the complete engine together starting on Saturday morning, complete it by Monday night and get it to Chico and Vintage Hot Rod (John Beck's dyno) on Tuesday.

    We flogged the crap out of it - made a LOT of pulls, overcame issues along the way and I believe we have a good tune and plan for both El Mirage and Bonneville. We're learning what this engine will produce and what abuse it will take - it has impressed all of us along the way. You might say that we're making it up as we go - there is no 'experience' or tribal knowledge to fall back on.

    Here is our last solid dyno run:

    1) 90% alcohol, 10% nitro, just over 19 lbs of boost. Still a little bit 'fat', but we like it that way. We made 653 HP on this run - about the 'max' we're going for. It is a torque monster - over 700 ft lbs by about 4700 rpm. Should be able to pull tall gears.

    Turn it up, scare your neighbors and make your dogs howl . . .

    Thanks for your support!

    B&S and the FlatCad Crew
    Last edited: Apr 12, 2014
  2. Sweet!

    Glad she held together

    Posted using the Full Custom H.A.M.B. App!
  3. Thanx for the Video Dale. It was great seeing you guys again, but damn was I tired by the time I got back............ ol age must be creeping up on me!
  4. Naw - wasn't the work, it was all the fricking jousting between you and Buddy! :D

    Great wrenchin with yah . . .

  5. 41 Dave
    Joined: May 23, 2005
    Posts: 2,594

    41 Dave

    Dale, Looks like you and the gang will have a very happy Flat Caddy mill in the Chevy this year. Wish you guys all the best in your runs this year.

  6. 29AVEE8
    Joined: Jun 28, 2008
    Posts: 1,384


    That is soooo impressive. Totally bitchin.
  7. dragsled
    Joined: May 12, 2011
    Posts: 1,977

    from Panama IA

    Hey Buddy,,Good To see you guys have stepped over to the Darkside:eek:, There's no going back now:D Keep sneaking up on it, You'll be at 80 and 90% next year:eek: Tim Jones
  8. Hell, I hope not - the whole dyno crew was a bit 'nervous' as it was. We were chatting with John Beck after the 7% nitro run and asking what he thought about going to 10% . . . his reply was a classic:

    John Beck:

    "Hmmmmm . . . lets see, if I combine all my years of experience with blown flathead Cadillac engines on Nitro . . . Hmmmm . . . well, I don't have any. You guys are making this history . . . it makes even me nervous!"​

    He then holds up both his hands and shows them shaking as well! :D

    Nobody knows the limits of this engine and our specific design/combination . . . and we'd really not like to see the connecting rods on the outside of the block. :eek:

    But then again . . . . wonder what she'll do????

  9. brad2v
    Joined: Jun 29, 2009
    Posts: 1,648


    Absolutely astounding gentlemen. Well done.
  10. Nobody knows the limits of this engine and our specific design/combination . . . and we'd really not like to see the connecting rods on the outside of the block. :eek:

    But then again . . . . wonder what she'll do????

    But then also remember the object of the lesson plan here.....200 mph at Bonneville in one piece, safely ........ then go balls out on the dyno till she rips the walls apart if ya want to, to find the "limits" of mans effort with a Cad Flathead. Love the sneaking up on it part, besides then I can get some dyno time with ya guys. An experience that I treasure, its a blast and a real learning curve for this ol fart!! :D:D:D:D
  11. 38FLATTIE
    Joined: Oct 26, 2008
    Posts: 4,350

    from Colorado

    I'd like to thank everyone for all of the support!

    Carl, it was good to see you again, and thank you for joining us!

    Abone, the A/F sensors won't read anything under a 9. Most of these tunes were very fat, and very safe. Look at the attached pic. You'll see we leaned out the mixture a bit, and had a monster run going, until we lost a head gasket at 4700 RPM's

    We've had issues with head gaskets, and have decided to try and correct the issue after El Mirage.

    Currently, we have to run .085" head gaskets, and even with o-rings and receiver grooves, it's hard to get and keep a good seal. We'll be deepening the head chambers .050", so that we can run a .035" head gasket.

    Hopefully this gives us the seal we need-if it does, we'll try some hotter tunes! Head gasket sealing has been an issue.

    We didn't dyno it last year, but 2 years ago it made 570HP

    Dave, we'll be running at El Mirage May 17th..........:D

    Attached Files:

  12. pitfarm
    Joined: Nov 5, 2007
    Posts: 63

    from UK

    Awesome is barely sufficient. What is your headgasket material... solid copper?
    Thanks, Tom.
  13. 38FLATTIE
    Joined: Oct 26, 2008
    Posts: 4,350

    from Colorado

    Yes, solid annealed copper
  14. fenderless
    Joined: Mar 31, 2006
    Posts: 1,285

    from Norway

    HP sure dosent come easy when you'r tikering With Flatheads;)
    Good number to work from. Hope you will overcome the headgasket issue.
    As you know, we have also ran the Flatty too fat. It's really a Challenge to find the right set-up, due to the low CR on the flathead. Timing is also a big factor on the Flathead, as "one" saltracer told me. lowering it made 50-70 HP. I think tipping the can will help alot. 20-25%:)?


  15. TR Waters
    Joined: Nov 18, 2006
    Posts: 1,439

    TR Waters
    from Vermont
    1. Early Hemi Tech

    Are those oil pressure numbers correct? If so, is that much pressure needed?
  16. Good observation! At Bonneville, by the end of a run (3 miles) we'll be down into the lower 90 lb range. We have to account for that in where we start as well.

    We're running large bearing clearances and heavy oil - which we can debate all day long (Buddy and I). I look at it like a lot of blown alcohol and nitro racers look at it - you need a lot of clearance, soft bearings, heavy oil and a good dry sump to make it live. We switched to this approach last year and all the bearings looked good (whereas the year before we had tighter clearances and thinner oil - and the bearings and the rod journals took a beating).

    Another factor that also comes into my thinking is that we're still running 3 mains (though we have a custom billet crank, large mains, steel caps, girdle, bubble-gum, bailing wire - to attempt to hold it together). With all that support, the crankshaft still wants to flex - especially in the middle. So having larger clearances being supported by high oil pressure gives us room for deflection - without having the bearings/crank come into contact.

    I know a lot of Flathead Ford racers that also use this technique --> loose is fast! Same goes with rod side clearances - keep them large. Getting a lot of oil through the bearings also is a major factor in bearing cooling - which is another thing to be aware of in BVille and other "long-track" engines.

    FYI: If you look at a lot of modern top-end blown-alcohol engines (tractors, boats, drags, etc) - they're running .0045 to .0055+ on the mains and .003+ on the rods . . . even with 5 mains, stout blocks and billet cranks - they've found these methods to make motors take the abuse of heavy racing. They're really quite similar to us - pushing engines to make huge horsepower on a package that originally couldn't have comprehended it.

    That is my story . . . take it for what it is worth!


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