New flexplate/ can changes ?

Discussion in 'Manton Push Rods Top Alcohol Tech Questions' started by lucky devil, Dec 14, 2012.

  1. TOL

    TOL Active Member

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    On a blown deal is cranking with a 139 tooth that much different then with a 168? I know directionally it would not be as good, but in the real world is it that big an issue?....
     
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  2. Mike Canter

    Mike Canter Top Dragster

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    It could be a problem because the engine will spin over at less of an rpm. I guess if you are using 24 volts the maybe no problem but maybe a problem with 16 volts. The othe problem is the tooth pitch of a 139 tooth ring is very different from a 168 and a 166 ring so one would have to change the starter pinion gear. Also the diameter of a 139 tooth ring is way smaller diameter so it probably will not clear the stands on a clutch and would require major repositioning of the starter to make correct tooth meshing.
     
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  3. TOL

    TOL Active Member

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    Thanks Mike. Seems to me that there is lot's of incentive for the can company's to come up with a 168 tooth solution. Hopefully they will. Weird how this has flown under the radar for so long......
     
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  4. Mike Canter

    Mike Canter Top Dragster

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    I am not sure that the can companies are planning to do anything to help because they don't want to pay all that money for SFI testing. That is big bucks. It is easier for them to leave the problem up to the clutch and flexplate companies or the individuals.
     
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  5. badbird

    badbird New Member

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    i think the 139 tooth deal is a flexplate solution only, which since i dumped the clutch and went to a rossler on my turbo car will fix my problem ( at a decent cost) but the clutch guys have limited options
    Mike did you ask trick about their redesigned liner which will let 168 fit??

    martin Lundkvist is sending me pics sometime today ill forward them if you like
     
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  6. bruce mullins

    bruce mullins Top Dragster

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    probell is making a billet steel 139 and a 166 tooth wheel that will fit in the new liner. the wheel was debuted at PRI.
     
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  7. jay70cuda

    jay70cuda Member

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    So how about we all work together and fix this problem . If you have the fix let us know. If you machine something to make work and it's a good fix keep us in the loop. To be blindsided like this is just uncalled for by those in charge.
     
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  8. badbird

    badbird New Member

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    blindsided...yes i just found out about this by accident ....no one is saying anything,
    could be down to embaressment that they have been messing with the rules and then got caught out to the racers cost........
     
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  9. badbird

    badbird New Member

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    Ok heres the deal

    from 15/11/ 2012 no can wil recert without the liner being right up to the midplate,

    this concernes trick cans only

    if the can was built befour 15/6/ 2010 the the 168 tooth ring wont fit
    if the can was built post 15/6/2010 then it will fit ...
    thats from trick themselves
     
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  10. JustinatAce

    JustinatAce Member

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    Mike, smaller OD flywheel and ring gear means it should turn faster with the starter. The problem might be the starter's ability to crank with less gear reduction from the flywheel. Figure that if you have an 11" clutch, the smallest I.D. of a ring gear you can most likely run safely would be in the 13" range. 11" Friction diameter, add at least another 1-1.5" or so for stud head clearance, and at least another inch in total diameter for meat around stud heads/pockets and stability.

    They may have created a bit of a monster with this deal.. Last year or two years ago, the clutch manufacturers of SFI voted on even keeping a 168 tooth flywheel certifiable, being as there have been numerous failures of the ring gears themselves, not the flywheels. We voted the deal down to keep allowing them, but it was an ultimatum that we needed to do a better job fastening the ring gears to the flywheels. That's 14" diameter piece of steel spinning 10,000+ at times. Something sitting on a clutch 13.25" in diameter spinning 10,000 RPM is moving almost 400mph.
     
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  11. Mike Canter

    Mike Canter Top Dragster

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    Let me add to that. Just got off the phone to Trick Ti. Yes over the last year and a half new Trick cans had a double diameter liner so they did fit the 168 tooth flywheel. Actually was two liners welded together. SFI has told them to stop doing that and these double size liner cans to be updated to the new one size liner when sent in for recert. So when your now fitting double size liner is sent in you are going to have to modify your starter ring.

    This change is not mandantory until 2014 but in order to get there it has to be phased in using the recertification date of the can. Since the recert is once a year it will take a year to get all the cans back and updated. So if you send a can in for recert they are going to update it.

    Justin, you are so right. I stand corrected on that the smaller starter ring gear will spin the motor over faster. I owe you a beer.
     
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    Last edited: Dec 18, 2012
  12. TOL

    TOL Active Member

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    Hey Justin, what do you think about the segmented ring gear approach like this one for example?....... http://www.dmpeinc.com/supercharger...tern-flex-plate-with-168-tooth-ring-gear.html
     
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  13. JustinatAce

    JustinatAce Member

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    As long as the fastening is adequate, I don't see why it wouldn't work. Most of us rely on the burst strength of the ring gear itself as well as the friction/sweat fit of the ring gear to aid in turning the flywheel to keep the stresses off the tabs and fasteners. The welded tabs we use just primarily serve as an aid to the burst strength of the ring gear at high RPM. Looks like he spread the contact surface area out more to aid in the starting stresses. It's a neat design. Would we change to such a thing? Probably not. Besides being Patent Pending, I don't want any more fastener supported mass or just mass in general on the OD than I absolutely have to have.
     
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    Last edited: Dec 18, 2012
  14. TOL

    TOL Active Member

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    I thought it was kind of neat in one aspect. If a conventional one piece ring does fail, then huge chunks of it are going to try to wreak havoc all of a sudden all at once. With the segmented approach a failure in one segment would not necessarily cause a sympathetic failure in the other segments. I hear your point about spinning all of those fasteners at the OD though.

    On a different note, what's actually required to SFI cert a clutch and or can these days? Does a person have to actually drive a clutch to failure to proof either the can design or the clutch design? If so that would be a pretty neat video to see :). Got any footage or links you can share?
     
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  15. hines

    hines Member

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    trick Can

    Want to get this correct. Having a can being built by trick right now so I called and asked last week if the 168 tooth ring gear will work. They told me yes but it sounds like you guys are saying they are going to put in a special liner that I will have to replace next year at recert time. I have to buy a new flexplate now to replace my reactor now so I don't want to waste money buying a 168 that will need to be replaced next year. Going to call meizer tomorrow cause the csr that I bought a month ago is off by .25" from the back of the flange. Starter only engages 20% into the ring ring.

    CN wide pan rail block hemi with a bruno
     
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  16. Mike Canter

    Mike Canter Top Dragster

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    According to Trick they say their new cans will work with a 168 tooth starter ring.
     
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  17. NITROBANDIT1

    NITROBANDIT1 LOST IN SPACE

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    FLYING DEBRIS (ie instant hole in hood)

    even though this all sounds like kaka now, we did have a ring gear that flew off a flexplate, went through the trans (auto) through the dash and windshield and landed on the track. after about 30 cars ran, somebody brought us the piece of the ring gear that came off. the engine had a slight vibration that wasnt normal, that was it. sfi said they only certify the flexplate, not the ring gear and when we showed them that was it. now that thing could have came out anywhere, and luckily not at the drivers foot! (door car). i can only think what could have happened, and im surprised with all these stupid self starting rules,it hasnt happend more. considering the proximety of these flying bits, i wouldnt make light of the rules after having this go wrong. i would put 2 cans on if i had to!!!!!!!!!!
     
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  18. JustinatAce

    JustinatAce Member

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    As Nitrobandit experienced, usually ring gear failures occur in segments anyway. I've seen ring gears spun off before, never had one fail on us that I know of, have seen the welds crack on the tabs over time. But the failures I have seen, it usually breaks somewhere between weld points creating a 3-6" piece of flying ring gear. I've never seen one completely thrown off, but that doesn't mean it can't happen.

    I couldn't tell you about what it takes to cert a can, but with clutches and presumably flexplates, we have to send it to an SFI approved lab for material certification and then typically send a unit or part off for destructive testing. It has to be able to withstand extended periods of forces typical of 150% of the maximum RPM it should see in normal use.

    Now, to get back more to the topic of the thread, let's say a 30 gram piece of ring gear does break off at 10,000RPM. That 30 gram piece of metal has a little more kinetic energy than a 124 Gr. 9mm bullet at 1150fps. And because of the mass, it will have almost twice the destructive power.
     
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  19. aj481x

    aj481x Member

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    and have for a couple of years. :cool:
     
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  20. badbird

    badbird New Member

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    september 2006 here in england we had a spectator killed when a piece of pro mod ring gear entered his chest, on its way to its victim it severed both shroud lines of the car next to it as it was at the finishline leaving the chutes hanging in the air .....nasty things flying ring gears
     
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