timing on 29 °

Discussion in 'Manton Push Rods Top Alcohol Tech Questions' started by danny, Aug 3, 2007.

  1. eli

    eli Banned

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    Your motor/ tune up knows what it wants just keep richining/ leaning nozzels till the cyl are all the same, then all you have to do is change the main jet to get the fuel mix right, you might not have to go with more timming, the low gear leanout will help you but only when you got every thing else right, if the fuel system is to lean you will shake the tires in the top of first gear, if you do use the leanout valve put a .040 jet in it to start, just for gigilles, look at the % differance from a .050 jet to a .055 jet, thats 18.71%, this is how my brother screwed himself at gainsvill this year, thats why i made that chart, so you can see that your changing the system big time when you mess with small nozzels if you go 5 at a time.P/S if your running a long stroke motor 4.500, I would leave the timming where it is we were running a 4.150 stroke with 30 *
     
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    Last edited: Aug 8, 2007
  2. danny

    danny compet elimin

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    Hi we are back from the races @ germany and everything going ok running our best et between 6.05 and 6.08 and no parts broken.we have the temps @ 1080 ° now and plugs are coloring gray/ white.we want to start working with the lean outs to get our 60 ft times back under 1 sec ;) and try to put a 5.99999 on the bords on the last race we have in 2 weeks:D grtz danny
     
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  3. eli

    eli Banned

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    work on your 330. the 60 will come.
    ET is in the clutch, and i don't mean Extraterrastial.
     
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  4. thjts

    thjts New Member

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    .014 would be US (inches). It can't be metric; way too small (1" = 25.4mm or 1.0mm = .039"...). But you're right, .014" is too small. Danny, you need to open up your plugs. That'll help.
     
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  5. Will Hanna

    Will Hanna We put the 'inside' in Top Alcohol
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    not recommended!

    i can promise you can go real fast with ngk 6061-10's gapped at .014" inches. if it makes you feel better, .016 is fine, but .014 is better. anything more than .020 will result in dropped cylinders and weak hp! seen it happen!

    the high cylinder pressure environment the plugs are in, less gap makes it easier for the mag to fire, and the spark has more intensity. opening the gap only makes it harder for the mag to fire, and easier for the pressure to 'blow' out.

    try if you like, but you've been warned.

    eli is right. 330' is where it's at. 61' to 660 is where alky tuners make their money. if it won't mph to the 1/8, go back and make it mph to the 1/8.
     
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  6. Bob Meyer

    Bob Meyer Comp Eliminator

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    Not trying to be a smartass, but I'm wondering if you still run a Prestolite distributor ?

    I've got a few moments here, so I'll tell a (true) bedtime story:
    In the mid 90's when the MSD 12's first came out, their instruction sheet said to run .024 gap! Almost everyone hates instuction sheets, Right ? Most were running .018 and never changed when they dumped their Mallory stuff.
    I've learned that pioneers get arrows in their ass, so I happened to ask a competitor/friend if he ever noticed what it said, he must have ran back to his trailer, read his sheet, and proceeded to make three miserable runs and a DNQ, losing a tenth and over 6 MPH!

    I asked if he tried it, he replied "yes, did'nt you?" :D
     
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  7. Bob Meyer

    Bob Meyer Comp Eliminator

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    Danny; as you may know, I follow FIA close, and have been to Santa Pod many times. Internet tuneups may be somewhat helpful, but I recommend you ask Steve Turner to go over what you've got when you get there. He used to run close to that combo and I'm sure he has not forgotten. Offer him some "quid", it'll be cheaper than flying someone over, just depends on how bad you want that "5".

    I tuned Steve Read to Europes first five in 1992 with stuff not near as good as you've got now, and I'd be happy for you to make it. Good show at Hockenhiem!
     
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  8. Dale H.

    Dale H. Member

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    I knew a guy that had a blown alchohol dragster that had a MSD 12 and had set the plugs at .025, then with no other changes other than changing the gap to .018 picked up 3 tenths in the quarter mile!
     
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  9. thjts

    thjts New Member

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    Plug Gap

    Yes, I wasn't implying going to anything as big as 25, that would definitely be asking for trouble. Apologies to Danny, I should have been more specific. 14 seems a bit on the tight side, but I'll always bow to experience (Will). No Bob, I'm not still using the Prestolite, my son uses it for a baby's rattle!
     
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  10. danny

    danny compet elimin

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    Hi That's why we have this site and the opportunity to talk and help, but if guy's like Will , Gene ,Bob and Mark and ...and ...say do this I do it with no further question because they are the guy's how knows what they are doing ;).I have asked over here and there was one guy telling me to set them on .035 and he's running alcohol cars for years.
    I appreciate it very match because its hard on the money if you just try out and brake parts.:mad:

    I have another question what's the max rpm on brooks 88 rods just before they go south?:confused: grtz danny
     
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  11. gubben

    gubben New Member

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    Hi, most of the TAFC:s from sweden run 0,35-0,40mm gap,thats 0,014-0,016 inch. I belive that hi ment to set the gap 0,35mm.
     
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  12. 23T Hemmee

    23T Hemmee Member

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    Will, would there be as much advantage with a milder tune-up deal like mine with a Mag III, obviously I've been in the dark ages, but until this thread I had never heard of running that tight of a gap, seems like a pretty good result for a very small change.
     
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  13. john348

    john348 Top Alcohol

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    11,700 is as high as i have ever got them,
    before i ran over them :D
     
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  14. eli

    eli Banned

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    engine balancing and hi rpms


    I wonder if anyone makes an engine balancer that can spin a v8 crank shaft at that rpm just to see if the crank goes into a differant harmonic balance at that rpm, you guys do know that a V8 crank can't be balanced perfictly, like a straight 6 or 4 cyl. engine
     
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  15. jim phillips

    jim phillips ta/fc

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    NOW THAT THERE IS FUNNY I DONT CARE WHO YOU ARE
     
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  16. bad andy

    bad andy New Member

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    Will, I liked what I read about leaning the car out in first gear. My question is how would a fella do that when he's using the manual air valve from Lenco?? I'd like to put the parts on and see what a change it makes in the 60 foot times,just not sure how to make it work.
     
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  17. Mike Canter

    Mike Canter Top Dragster

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    Andy, why would you want to lean a blower car out in first gear? Don't you need fuel down low to produce torque and that is why you use a High Speed Bypass to make it rich down low and leaner up high for horsepower?
     
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  18. bad andy

    bad andy New Member

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    Mike, I agree 100 percent with your statement. If you go back to page 2 and read Wills' post,that is what I was asking him about. I run the "normal" hi speed right now and it works very well. I just thought I may possibly tinker with the valve Will was talking about to see if my 60 foot times dropped. It could be a fun little secret.
     
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  19. eli

    eli Banned

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    Will was talking about a screw blower car not a roots.:rolleyes::)
     
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  20. Mike Canter

    Mike Canter Top Dragster

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    Even a screw blower needs a different AFR down low for torque. The motor is just dumb and doesn't know what blower is on the top all it sees is the air to fuel mixture coming through that intake valve.

    It could be all a matter of reference as to what you think you are doing with the fuel system. Like I said the motor is dumb and all it cares about is a richer AFR for pulling through first gear and a leaner mixture in high gear. Now you have to know what is actually happening to the density altitude of the air going down the intake runner. The screw blower doesn't heat the air as much from friction like the rootes blower but the higher the boost created by the screw blower the more the air is heated by compression. It maybe that the lower friction temps that result in different air temps going into the motor are clower to being correct with the screw blower up high. More self correcting.
     
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