Ask the Bob's AKA GN7 bp298
+ Reply to Thread
Page 1 of 5 1 2 3 4 ... LastLast
Results 1 to 14 of 57

Thread:
Ask the Bob's AKA GN7 bp298

  1. #1
    Senior Member
    Join Date
    Aug 2008
    Posts
    178

    Default Ask the Bob's AKA GN7 bp298

    So Bob's I have this engine and my CHT temps are High on Cylinders 1,2,and 9 The EGT's are within 75 deg over all nine. Oil temp climes to near red line at low to mid power settings. The engine is 6:1 CR with a blower I run 100LL only timing is "locked out at 25' with dual mags. The Prop is 108" power prop. Power setting is 1800 RPM 28inches fuel burn 19.7 GPH at this power. What is causing these high CHT's? On a side note you to are great to have here

  2. Remove Advertisements
    PerformanceBoats.com
    Advertisements
     

  3. #2
    gn7
    gn7 is offline
    Senior Member gn7's Avatar
    Join Date
    Jan 2008
    Posts
    25,975

    Default

    I am sorry, I don't deal in 3, 5 and 9 cylinder engines.

    First, I would dump that shit 100LL and put it on Q16.
    Second, stop running Wal Mart Tech 2000 oil.

    Is this thing a radial?

    BTW, I have it on good authority that EGT are useless information. Best to just ignore them, crank in some more fuel and boost and let let it eat. Without good accurate O2 readings, you're just throwing darts



    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; 06-18-2013 at 05:04 PM.

  4. #3
    Senior Member
    Join Date
    Jun 2011
    Posts
    182

    Default

    Is this a float plane?

  5. Remove Advertisements
    PerformanceBoats.com
    Advertisements
     

  6. #4
    gn7
    gn7 is offline
    Senior Member gn7's Avatar
    Join Date
    Jan 2008
    Posts
    25,975

    Default

    Quote Originally Posted by Checkmate21 View Post
    Is this a float plane?
    Or an air boat. I don't think Bottom Feeder is redneck enough for an air boat.



    100% free webcam site! | Awesome chicks and it is absolutely free! | Watch free live sex cam - easy as 1-2-3

  7. #5
    Or Seth, either one Budweiser's Avatar
    Join Date
    Dec 2007
    Location
    Tower Park Resort, Lodi, CA
    Posts
    3,270

    Default

    Quote Originally Posted by gn7 View Post
    Or an air boat. I don't think Bottom Feeder is redneck enough for an air boat.
    With a 9 foot prop, whatever it is, it's not small.

  8. #6
    Senior Member
    Join Date
    Aug 2008
    Posts
    178

    Default

    Why yes P&W R-985. It is a legit question that has been kicking my ass. And their are only two approved oils and one fuel. But hey its a 50 year old dry sump motor 280 HP from 985 inches no wonder they are "dependable" Sorry I don't support Wallys, wish the parts store was still down on the corner. Funny story back when they were open the group of racers i ran around with decided we needed a cash account so we could work toward better pricing in one year that group spent twice as much with them as their largest commercial account. But in the end that shit hole schucks, checker kragen won out, and the asshole who held the lease on the land that priced them out to put a quicky mart. Now i have to drive 20+ miles to get to another mom and pop shop. sorry rant over Whats with them -12 oil lines u need that much flow for grease you call oil not that you GN types are tough on motors

  9. #7
    Senior Member bp298's Avatar
    Join Date
    Dec 2007
    Location
    LHC
    Posts
    6,570

    Default

    Quote Originally Posted by bottom feeder View Post
    So Bob's I have this engine and my CHT temps are High on Cylinders 1,2,and 9 The EGT's are within 75 deg over all nine. Oil temp climes to near red line at low to mid power settings. The engine is 6:1 CR with a blower I run 100LL only timing is "locked out at 25' with dual mags. The Prop is 108" power prop. Power setting is 1800 RPM 28inches fuel burn 19.7 GPH at this power. What is causing these high CHT's? On a side note you to are great to have here
    this is very simple. 1. you need to clean the bird feathers out of the cooling fins for cylinders 1, 2, and 9 from the last seagull swarm you ran into. 2. you need a wider band egt instrument. that way, 75* doesn't look like so much. 3. 70wt kendall will solve your oil temp problems, as well as cleaning the bird feathers out of the oil cooler fins. 4. go with a 106" "speed" prop. may not get there as quick, but it'll haulass on the big end. I heard the lodi bunch has one that kicks ass and makes mincemeat out of seagulls so the feathers wont' stick.
    and I concur with the gn. jack up the boost, turn up the fuel and let it ride.
    this is as good it gits without the superwideband o2....

  10. #8
    Senior Member
    Join Date
    Aug 2008
    Posts
    178

    Default

    Dehaviland beaver no floats. Bush wheels baby. And an air boat could be a ton of fun in the rivers no loss of thrust in the foam

  11. #9
    Senior Member
    Join Date
    Aug 2008
    Posts
    178

    Default

    you guys great I here ya on the egt but that is as good as it gets in "approved" Just use them for overall ballance as the temp means jack.

  12. #10
    gn7
    gn7 is offline
    Senior Member gn7's Avatar
    Join Date
    Jan 2008
    Posts
    25,975

    Default

    I understand this is a problem with some of the radial PW. But usually its with cylinders that are 4 rows back.

    Have you tried flying it at a higher altitude? Colder and thinner air. Less drag, colder cooling air, richer fuel mixture. All positives.



    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; 06-18-2013 at 05:43 PM.

  13. #11
    Senior Member
    Join Date
    Aug 2008
    Posts
    178

    Default

    4 rows back yea way out of the budget. GN7 are you going to be here for burley? yea fine at alt. or anytime ambient is 75'F. 90 to day not so good. besides i am scared of heights
    Last edited by bottom feeder; 06-18-2013 at 05:51 PM.

  14. #12
    Senior Member
    Join Date
    Aug 2008
    Posts
    178

    Default

    BP how is the new hot rod treating you? I need to get to another Drag Boat race allways good times.

  15. #13
    gn7
    gn7 is offline
    Senior Member gn7's Avatar
    Join Date
    Jan 2008
    Posts
    25,975

    Default

    Quote Originally Posted by bottom feeder View Post
    4 rows back yea way out of the budget. GN7 are you going to be here for burley? yea fine at alt. or anytime ambient is 75'F. 90 to day not so good. besides i am scared of heights
    No, we are siiting this one out and letting someone else win one for a change



    100% free webcam site! | Awesome chicks and it is absolutely free! | Watch free live sex cam - easy as 1-2-3

  16. #14
    steelcomp was here
    Join Date
    Dec 2007
    Location
    n/e TN
    Posts
    26,269

    Default

    Thermocouples under the plugs? Have you tested them by moving them aorund?
    If God is your co-pilot, change seats!
    Acts 2:38, the perfect answer to the perfect question.

+ Reply to Thread
Page 1 of 5 1 2 3 4 ... LastLast

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

Tags for this Thread

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