Mild 6-71 5-7lbs on BBC. Initial timing?
+ Reply to Thread
Results 1 to 13 of 13

Thread:
Mild 6-71 5-7lbs on BBC. Initial timing?

  1. #1
    Senior Member norcal73's Avatar
    Join Date
    Mar 2008
    Location
    Lake County, Ca
    Posts
    576

    Default Mild 6-71 5-7lbs on BBC. Initial timing?

    Fot a mild built set-up 454 BBC with an old school 6-71 on 5-7 lbs boost, what is best on timing? Initial? Advanced? or lock it out? Cam is a Extreme Marine 278H.

    norcal73

  2. Remove Advertisements
    PerformanceBoats.com
    Advertisements
     

  3. #2
    i'm back!! 1QuickCP's Avatar
    Join Date
    Jun 2009
    Location
    Montana
    Posts
    687

    Default

    locked out , 32 to 35. for starters imho

  4. #3
    I'm famous ! Lucky's Avatar
    Join Date
    Dec 2007
    Location
    Ukiah,Ca
    Posts
    7,043

    Default

    32
    " my carbon footprint is gonna kick your green ass"


    Quote Originally Posted by 396_Ways_To_Spit View Post
    WOWO!!!!! THat has to be the most beautiful crank that Ive ever seen!!!!!!!!!!!!!!!!


    Quote Originally Posted by MAXIMUS View Post
    He has been allowing me to park my equipment in his backyard for a few years now...
    [/SIGPIC]

  5. Remove Advertisements
    PerformanceBoats.com
    Advertisements
     

  6. #4
    Senior Member jockorace's Avatar
    Join Date
    Feb 2008
    Location
    Whitewright, TX
    Posts
    3,359

    Default What fuel???

    I would think that before anyone can recommend a (total) timing number, you would have to know what type of fuel he will be running. Since he didn't mention it, I'm guessing maybe pump gas? If so, 35 degrees seems a bit much with 7 psi of boost. I run 34-36 degrees with 110 race gas (9 psi) Jocko

  7. #5
    Senior Member norcal73's Avatar
    Join Date
    Mar 2008
    Location
    Lake County, Ca
    Posts
    576

    Default

    I did the first fire up with Sunoco race gas at 8.75 a gallon, even though it probably didnt need it. So would 32 be a good number?

    norcal73

    Quote Originally Posted by jockorace View Post
    I would think that before anyone can recommend a (total) timing number, you would have to know what type of fuel he will be running. Since he didn't mention it, I'm guessing maybe pump gas? If so, 35 degrees seems a bit much with 7 psi of boost. I run 34-36 degrees with 110 race gas (9 psi) Jocko

  8. #6
    Senior Member jockorace's Avatar
    Join Date
    Feb 2008
    Location
    Whitewright, TX
    Posts
    3,359

    Default

    IMO 32 would be the max on pump gas. Looking at the BDS chart for total compression.....if you have 8.5-1 + 7 psi = 12.5-1 compression. I would keep it at 30 degrees so you have some margin in case you get a bad tank of gas.
    You know, when you're running headers you cannot hear any detonation.
    Just sayin.
    All the years I ran my blown flat at Lakeport was on Av-Gas. Everyone I knew with any horsepower back then just went to the airport and filled up. LL100 is the best bang for your $$$ Jocko

  9. #7
    Senior Member smitt19's Avatar
    Join Date
    Jan 2008
    Location
    carmichael, ca
    Posts
    358

    Default timing

    I never ran more than 30 locked out , 2 degrees more made no noticeable diff on the dyno

  10. #8
    gn7
    gn7 is offline
    Senior Member gn7's Avatar
    Join Date
    Jan 2008
    Posts
    25,975

    Default

    This funny. Only Jockorace makes any comment about CR and even then he was assuming. And the head material, and chamber design is of no concern? Bottom line, like smitt19 stated, there isn't enough there after about 30* to make the risk worth it. I would say 32 max if the CR is 8.5 and alumn heads. Specially with that cam.



    100% free webcam site! | Awesome chicks and it is absolutely free! | Watch free live sex cam - easy as 1-2-3
    Last edited by gn7; 08-20-2010 at 09:25 AM.

  11. #9
    Senior Member norcal73's Avatar
    Join Date
    Mar 2008
    Location
    Lake County, Ca
    Posts
    576

    Default

    049 heads with some work done to them. Exhaust been opened up, new valves, springs.


    Quote Originally Posted by gn7 View Post
    This funny. Only Jockorace makes any comment about CR and even then he was assuming. And the head material, and chamber design is of no concern? Bottom line, like smitt19 stated, there isn't enough there after about 30* to make the risk worth it. I would say 32 max if the CR is 8.5 and alumn heads. Specially with that cam.

  12. #10
    Senior Member norcal73's Avatar
    Join Date
    Mar 2008
    Location
    Lake County, Ca
    Posts
    576

    Default

    Dry stacking it. Huh, what, hearing? lol. Just wanting something that will last til the funds permit a better built mill. Did you know Frieghttrain Peters, Blowin Rowan, Roy Parmentier?

    norcal73




    Quote Originally Posted by jockorace View Post
    IMO 32 would be the max on pump gas. Looking at the BDS chart for total compression.....if you have 8.5-1 + 7 psi = 12.5-1 compression. I would keep it at 30 degrees so you have some margin in case you get a bad tank of gas.
    You know, when you're running headers you cannot hear any detonation.
    Just sayin.
    All the years I ran my blown flat at Lakeport was on Av-Gas. Everyone I knew with any horsepower back then just went to the airport and filled up. LL100 is the best bang for your $$$ Jocko

  13. #11
    Senior Member jockorace's Avatar
    Join Date
    Feb 2008
    Location
    Whitewright, TX
    Posts
    3,359

    Default

    Yes, all those guys (and many others) were the top dogs during Clearlake's heyday of NorCal ski racing. Some of the others were Dick Seiler (I have his 19' Hallet SS now), Bud Simi, Bill Simpson, Hal Riedel, Chuck Marino, etc.
    I currently own two boats with Gary Rowen (RIP) motors (one blown & one twin-turbo). Gary's motors now would be considered somewhat old school, but I will say this, they stayed together and lived. In my case for multiple seasons!

    On the subject of ignition timing, boost, octane......Hal Riedel and I used to split a 55 gal drum of TOLUENE for the summer. We would add 10% toluene to the av-gas to bump the octane just to be on the safe side of detonation.


    Jeez, don't ask an old guy about the past......he'll never shut up! Jocko

  14. #12
    Frank my lord Blown$um's Avatar
    Join Date
    Jul 2009
    Location
    ca
    Posts
    186

    Default safe than sorry

    i tend to leave my blower motors at 28* mark im currently running a blown alcohol hydro and a blown 520 inch motor in my drag car , the car ive pushed as hard as 31 percent over driven on a 8-71 and a 200 shot through blower surprisingly it made down the quarter mile at fomosa bakerfield and didnt spill its beans. what im getting at is you can lock it out at a safe number , it will start easier and lower exhaust temps , and be more forgiving for those daily cruises but when you want to speed it up a little bit throw in a little race gas, do a pulley swap and give it hell , not ever worrying about the timing.
    Last edited by Blown$um; 08-21-2010 at 01:47 AM.
    "Ill be your huckleberry"

  15. #13
    Senior Member norcal73's Avatar
    Join Date
    Mar 2008
    Location
    Lake County, Ca
    Posts
    576

    Default

    Dizzy locked-out at 30. Ran great. What oil would be best to to run in the engine now that the break-in period is done?

+ Reply to Thread

Quick Reply Quick Reply

Register Now

Please enter the name by which you would like to log-in and be known on this site.

Please enter a password for your user account. Note that passwords are case-sensitive.

Please enter a valid email address for yourself.

Please select your insurance company (Optional)

Log-in

Digg This Thread

Posting Permissions

  • You may post new threads
  • You may post replies
  • You may not post attachments
  • You may not edit your posts
  •  
 

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95