just want some reassurance on combo choices

Discussion in 'Engine: Repairs , Modifications ,trouble shooting ' started by Grumpy, Aug 26, 2018.

  1. Grumpy

    Grumpy The Grumpy Grease Monkey mechanical engineer. Staff Member




    sounds like a good combo, yes Id go with the 210 cc heads,
    [​IMG]
    Air Flow Detail #176 SBC All American Head - 210cc Runner

    Pro Filer Small Block Chevy All American Heads with 210cc Intake Runner, 2.08" Intake Valve and 1.60" exhaust valve. Flow data based on Cylinder #1 intake and exhaust port. Flow measured at 28" of depression.

    Air Flow Detail #176 - 210cc Runner

    Lift Intake CFM Exh CFM % Exh/Int
    0.200 145 110 76%
    0.300 207 145 70%
    0.400 258 180 70%
    0.500 283 206 73%
    0.600 285 213 75%
    0.700 291 216 74%
    0.800 297 218 73%
    Air Flow Chart #176 - 210cc Runner

    [​IMG]


    [​IMG]
    https://www.profilerperformance.com/176-sbc-23-degree-heads.html

    you might be worried the larger ports potentially kill lower rpm torque..DON'T BE!
    the rear gear and manual trans, and the high static compression will more than off set that,you will be fine!
    I would specify the 72 cc combustion chambers on the 210cc heads
    your potentially dealing with detonation issues more than a loss of off idle torque,
    youll want a cam with a bit of duration to bleed down the lower rpm effective cylinder compression,
    and because of the manual transmission and rear gear ratio,
    and displacement, you can get away with more cam duration, than most people
    Id select the air gap dual plane intake and most likely a crane 119651 hydraulic roller cam

    (personally ID install it split overlap or strait up)
    and roller rockers, don,t forget youll want a 7-8 quart baffled oil pan
    rock solid durability and a wide torque curve in the useful rpm range, is more important that peak power
    , 1 3/4 full length headers
    verify all clearances and yes youll need premium octane fuel.
    MAYBE RICK CAN POST A SOFTWARE DYNO??

    [​IMG]
    keep in mind this is a small base circle cam with asymmetrical cam lobes you must use the .050 lift and duration numbers in calcs
    [​IMG]
    https://www.summitracing.com/parts/...MIisTdgsuL3QIVlrjACh0EnAAjEAAYASAAEgKCTvD_BwE
     
    Last edited: Aug 28, 2018
  2. I'm also concerned about detonation. I almost changed components based on that issue. I have been looking at several cams and plugging intake closing degrees in to try to get the DCR where it's manageable. I do have decent 93 octane around. My deck is at 0 currently if my measurements add up.
     
  3. I like that cam. I have another for a previous build by Mike Jones, but going by the cam card there is no way I can get by with it. The intake valve close is way too low. My static compression was too high using Rick's spreadsheet
     
    Last edited by a moderator: Aug 28, 2018
  4. Indycars

    Indycars Administrator Staff Member

    I can do that, all I need is the input data all in one place.

    Bore & Stroke:
    Rod Length:
    Heads with flow numbers:
    Combustion Chamber Size in CC’s:
    Dome Volume: For a domed piston use a (-) negative number.
    Valve Reliefs Volume: For a piston with valve reliefs use a + positive number.
    Deck Clearance:
    Head Gasket Bore:
    Head Gasket Thichness:
    Valve Sizes I/E:
    Intake Manifold Model Type [Single or Dual Plane]
    .... Model #:

    Carburetor Size (CFM):
    SCR & DCR:Header Tube Diameter: Small, Medium, Large (1-5/8", or , or)
    Cam Card:
    Cam Installed per Cam Card, or Retarded or Advanced:
    Rocker Ratio:
     
  5.  
  6. Here's some inputs
    Bore & Stroke: 4.125, 3.75
    Rod Length:6.0
    Heads with flow numbers: Profiler 210cc as cast
    Combustion Chamber Size in CC’s: 72
    LiftIntake CFMExh CFM% Exh/Int
    0.200 145 11076%
    0.300 207 145 70%
    0.400 258 180 70%
    0.500 283 206 73%
    0.600 285 213 75%
    0.700 291 216 74%
    0.800 297 218 73%
    Dome Volume: For a domed piston use a (-) negative number.
    Valve Reliefs Volume: For a piston with valve reliefs use a + positive number.+5
    Deck Clearance:0.00
    Head Gasket Bore:4.165
    Head Gasket Thichness:.039
    Valve Sizes I/E:2.08/1.60
    Intake Manifold Model Type [Single or Dual Plane]
    .... Model #:dual Edelbrock rpm air gap 7501. I have a Holley 300-25 also

    Carburetor Size (CFM):750
    SCR & DCR:Header Tube Diameter: Small, Medium, Large (1-5/8", or , or) 1.75" full length tube, 10.5 static
    Cam Card: crane 19651 per grumpy's reccomendation. Pick another if you like. I haven't bought one yet. My DCR will dictate what I can run with 93 octane
    Cam Installed per Cam Card, or Retarded or Advanced: Per card straight up
    Rocker Ratio:1.
     
  7. What about that comp xr294hr? I pulled it's specs
     

    Attached Files:

  8. Maniacmechanic1

    Maniacmechanic1 solid fixture here in the forum

    I can tell you already the Engine will like a Single pattern cam.
    Like Iskenderien is famous for.
    The E/I Ratio is very Good on the cylinder heads.

    Dual pattern often used here.
    And to knock down the dynamic compression ratio.
     
  9. Which isky would you suggest? All I saw in my isky catalog for hydraulic rollers were dual pattern cams.
     
    Last edited: Aug 26, 2018
  10. Maniacmechanic1

    Maniacmechanic1 solid fixture here in the forum

    I have not looked in a while.
    Isky or When You call ask for Ron Iskenderien.
    He will talk to you.
    A Great Guy.
    He ground me up another Pontiac V8 Full drag race cam grind.
    Full Danger Zone Drag Race to win profile.

    Latest catalog online I saw lists the top sellers.
    He can grind any past cam profile or a one off.
    Cost is right.

    Grumpy and Rick like the dynamic compression ratio calculators.
    Push the limit on 93 octane.
    Can be flawed because there is effective compression ratio and not so easily predicted Volumetric Efficiency Cylinder fill with Engine running.

    Look in the morning for you Isky.
     
  11. Maniacmechanic1

    Maniacmechanic1 solid fixture here in the forum

  12. Nice sou
    Nice sound, even with that noisy Pete Jackson! I would need more dynamat
     
  13. Maniacmechanic1

    Maniacmechanic1 solid fixture here in the forum

    Running short on time this morning to look in my ISKY Catalogs.
    Have them back to 1970 year.

    I will have to look online when I have time at work.
    Have a general idea what your looking for.
    1970 LT-1 Z8 Sound and a bit more performance.
    Found a Test Dyno chart with the CC XR294.

    This a Race Car ?
    OK with mixing race gas with pump gasoline or using Torco octane booster?
    VP makes an excellent octane booster.

    Street car ? Running 87, 89, 91 Or 93 octane.
    Pump gas is not the cheep today again.

    Different ways to view and each have different goals.
    I prefer max performance and that means Race fuel 110 for me.
     
  14. You are dead on with 1970 sound and a good all around performance mill. I want to stick with 93, I carry a bottle of torco just in case I get ahold of bad fuel or someone doesn't have 93 available. Usually isn't a problem. I don't want to mix the fuel if I don't have to. I'd honestly rather drop compression if I have to. I left out the part about power brakes.... I have a vacuum canister I can use. I'm pretty much always on the street, rarely at the track
     
  15. Maniacmechanic1

    Maniacmechanic1 solid fixture here in the forum

    Dyno Results

    Camshaft Part # 12-254-3 Grind # XE294H-10
    Duration @ 0.006":
    294° / 306 Duration @ 0.050": 250° / 256°
    Max Lift w/ 1.5RR: .519" / .523" Lobe Separation: 110°
    Lobe ID#'s: 5449 / 5231 Intake Centerline: 106°
    Engine Type: Chevrolet 350 Small Block
    Bore: 4.040" Stroke: 3.480"
    Displacement: 356ci Compression: 9.25:1
    Heads: Dart Sportsman II Intake: Edelbrock Victor Jr.
    Carburetor: Holley 750 dbl. pmp. Exhaust: 1 3/4" Headers
    Max Torque: 394 ft*lbs @ 4100 RPM Max Power: 415 HP @ 5800 RPM
    Manifold Vacuum: 8" Hg @ 1000 RPM & 10.5" Hg @ 1200 RPM w/ no load.

    [​IMG]
     
  16. Grumpy

    Grumpy The Grumpy Grease Monkey mechanical engineer. Staff Member

    built correctly, and if using better parts than those listed, with that comp cams 9.25 compression,356,
    a 400 sbc can rather easily add well over 80-100 or more added, horse power to what that graph above shows

    Christopher


    you might want to read through this thread from start to finish
    keep in mind RICKS engine while similar to what you list is designed to work,
    as brisk performance in a daily driven car with an auto trans,
    with over drive so he needs more low rpm off idle responsive, and lower cruise rpm torque.
    (thus a minor compromise to make it a bit more traffic friendly)
    your manual trans is more flexible, the heads you selected flow better, so why not take advantage


    http://garage.grumpysperformance.com/index.php?threads/tbucket-engine-project-dart-shp.3814/
     
    Last edited: Aug 27, 2018
  17. Maniacmechanic1

    Maniacmechanic1 solid fixture here in the forum

    What can be done on the spot is retard the total ignition advance to 4 degrees less than what was optimal on a given fuel octane that worked prior.
    Two flexiable carbs come to mind to make that possible.
    Holley 4150 series Double pumper or Street Avenger 4150 Holley with vacuum secondary.
    And a 800 cfm Q-jet off a 1973-74 SD 455 TA or 1970-171 Buick Stage 1 455.

    Holley most available and affordable.

    MSD Used to make a timing control retard box that connected up with a Racing 6AL Box.
    I used in the past.
    It worked.
    Modern quality real spotty by MSD.
    If any way possible try & find Vintage MSD 6AL from 1994-1999. Best quailty & still made in Texas USA all.

    Best way I have found looking at cams & plausible pump gas octane rating chosen with no detonation is look at the cranking compression.
    87 octane you need 150-165 psi.

    Step up to 93 octane with 195-210 psi Max.

    185-190 psi best target on 93 octane.

    Some engines allow 190 psi cranking on 87 octane, superior cooling system needed & a Huge Fat radiator.
     
  18. Maniacmechanic1

    Maniacmechanic1 solid fixture here in the forum

    MSD Timing Retard control would allow me to advance or retard ignition advance up to 15 degrees from the drivers seat with a twist of the potentiometer knob & looking at the scale on it.
     
  19. Maniacmechanic1

    Maniacmechanic1 solid fixture here in the forum

    Anyone that Reads Ricks main thread needs 100 hours free time Grumpy.
     
  20. Maniacmechanic1

    Maniacmechanic1 solid fixture here in the forum

    I like Longer duration cams like you chose.
    Volumetric efficiency cylinder fill is drastic improved in general.
    Throws all the online dynamic calculators off.
    Kinda worthless then again not.
    Rick has one that calculates cranking compression.
    The one to check and use.
     

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