NHRA Pro Stock and spec heads

Discussion in 'The Comp Buzz' started by Jeremy Tanksley, Jul 29, 2013.

  1. deuces wild

    deuces wild Member

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    Pro Stock

    Greg Stanfield said they need to limit rpm. With those engines north of 11,000 rpm that's where the valvetrain expense is coming from. KJ said the other day 100,000 a year or something crazy like that!
     
  2. Jack Issi

    Jack Issi Member

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    There seems to be no practical answer.
     
    #42 Jack Issi, Aug 7, 2013
    Last edited: Aug 7, 2013
  3. Arnie

    Arnie New Member

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    like!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
     
  4. Jeremy Tanksley

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    Greg has a good point. However, doesn't it seem like an rpm limit would put development at more of a halt than a spec head ever would? Is this really a good thing?

    Also, Kurt is right about valvetrain expenses. Between both cars, considering there's 23 races a year, dozens of test runs, and many pulls on the dyno, just in valvesprings alone they spend thousands a year, not including other valvetrain developments. Their engines see quite a lot of run time. For that, I can see his numbers to be realistic. However, the Johnson's develop their own heads, and save considerably. Most of the front runners, or all of them, buy their heads. Different ball game. Maybe even the Johnson's could save money with a spec head?
     
    #44 Jeremy Tanksley, Aug 8, 2013
    Last edited: Aug 8, 2013
  5. Bob Book

    Bob Book Active Member

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    Jack - in my opinion 2 things would make an easy fix - 10,500 RPM limit and you have to race the engine you qualify with.
     
  6. Clint Neff

    Clint Neff Well-Known Member

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    Bob great answer. Make it like the old Top Fuel days. They could only have one block. They could have numerous cyl heads, pistons etc but had to make it work pretty much with one motor.
     
  7. Jon Hansen

    Jon Hansen Member

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    Would placing a limit on valve lift work ? Easy to check and no team has to buy new heads, blocks, etc. It's the RPM that costs money
     
  8. Jeremy Tanksley

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    You guys are right about rpm's and cost, but are missing one key step.

    You could change valvesprings every run and every pull on the dyno, and rent a spintron tester once a month of a race season, and you'd still spend more on heads in a single season if you're a front runner in Pro Stock.
     
    #48 Jeremy Tanksley, Aug 9, 2013
    Last edited: Aug 10, 2013
  9. comp 670

    comp 670 Active Member

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    Mabie the answer is for teams to quit paying millions for heads from one guy and spend those millions doing things in house.... I REALLY hope there is never a "spec" head or engine in PS. Its the top of the game in n/a racing and should stay that way.
     
  10. goneracin

    goneracin Member

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    this is not true.
    Im not sure if you consider us a "front runner" but we can qualify at or near the top for the most part and run with most everyone. I dont know where you get your numbers from, but you must think we pay a lot more for heads than we do. I cant vouch for what anyone else pays, but you are so far from reality with that statement and our program its not funny.
    Im going to retire from this thread now, as nothing good can come from it from here on out IMO.
     
  11. Jack Issi

    Jack Issi Member

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    you can't legislate technology.....consider super modified... the original concept by Rick Voegelin compared to where it is today... cost limiting factors ALL went by the wayside. starting with the 461x heads to today's 15k set of heads. I still believe there is no practical answer to achieve PS parody..... the HAVE's win!
     
    #51 Jack Issi, Aug 9, 2013
    Last edited: Aug 10, 2013
  12. Bruce H

    Bruce H Member

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    The class is called Pro Stock. Not entry level stock or mediocre stock. Running this class will always consume cubic dollars as the nature of the beast is to get better. What really needs addressed is what parts are legal to run. Pneumatic springs would reduce valvetrain problems. This class is supposed to be about innovation and technology. RPM limits are possible but hard to enforce. I always believed rods, pistons and blocks were RPM limiters. Nobody can afford to grenade an engine every run. Hard to qualify that way.
     
  13. cutta

    cutta Member

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    The possible problem I see with pneumatic mechanisms for valves is the control system utilized. I'm not really sure of how advanced the technology is, but I could definitely see a substantial amount of money being poured into some sort of control mechanism for the valves. The amount of valve lift profiles one could use are limitless and the research involved in finding the most optimum one could be significant.
     
  14. Jeremy Tanksley

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    Considering no numbers have been thrown out there, you're making no sense whatsoever. I don't know what your team spends on heads. It might be a lot less than others. Regardless though, if what I know differs from what you know about the costs of heads in Pro Stock, then someone other than yourself in YOUR camp is a liar. Unless you truly don't know. I'll leave it at that.

    Lastly, just supplying information and asking questions here. The biggest question has been whether spec heads will reduce costs in Pro Stock, as well as other associated questions. Perhaps the best responses I've gotten so far are the ones from Mark Wolfe.
     
    #54 Jeremy Tanksley, Aug 10, 2013
    Last edited: Aug 11, 2013
  15. comp 670

    comp 670 Active Member

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    Jeremy, you really have not supplied any info... You just say they cost to much yet will not say what the true cost is....

    Goneracin has been building PS engines for a lot of years so it's a pretty safe bet he knows exactly what stuff costs and even what the other teams are paying for parts. PS is a VERY small group of people and everybody pretty much knows what the others are doing..
     
  16. Jeremy Tanksley

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    I've agreed to not use numbers. Plain and simple.

    But the numbers aren't important. It's the fact that the costs are high, and reducing these costs could bring in more cars. Is bringing in more cars a possibility with a spec head?
     
    #56 Jeremy Tanksley, Aug 10, 2013
    Last edited: Aug 10, 2013
  17. comp 670

    comp 670 Active Member

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    I totally understand. I spent a lot of time at the seattle national talking about PS teams and what they spend with a few of the team owners and it's nuts. The prob is that there are those out there that can afford to spend like that so they do. If I had that kind of money I'd do the same thing.

    The things I'd love to see is a spec shock, mandate staying with a 9.5 rear end and a 10,500 rpm limit. Those three things would get me back into PS... Leave the engines alone.
     
  18. Jeremy Tanksley

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    A spec shock would be nice.

    And to point one thing out to everyone, the goal isn't to strong-arm a rich man into spending the same as a poor man. The goal is to help the class expand. NHRA going around begging one racer at the Denver Nats to enter Pro Stock with his car isn't the best way to get more cars in the class.

    As always, thanks Mark for your input.
     
    #58 Jeremy Tanksley, Aug 10, 2013
    Last edited: Aug 10, 2013
  19. Rob Harrison

    Rob Harrison Well-Known Member

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    Rpm

    Isn't RPM the biggest problem ? F1 limited RPM and they can use air cups , the stroke of the crank becomes the limiter @ 20,000 . Limit the RPM in P/S , don't need 520 Lbs seat pressure , less load on everything in the valve train , not in valve float , in general , less destruction .

    In the early development years of Igor , we ran a cam combo that was in chaos @ 7,800 on the spinitron , we would shift it @ 8,400 , if the RPM got to 8,600 , it would blow the lifters apart on no. 6 . We had to lower the seat pressure to 200 to make it work ( if you could call it that ) the dynamics of the valve train operation was mind blowing , but when we tripped on a design that was stable , we had valve control @ 9,000 on the spinitron , spring pressure back to normal ......HP showed up out of nowhere.

    If an RPM limit was put in place for P/S , those guy's are the best in the business , before long , they would be making more power @ lower RPM and some measure of reliability would exist , let alone less cost .
     
  20. Bob Book

    Bob Book Active Member

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    IMO spec heads would lower the cost like a Holley 850 lowers the cost of a C/SMA Engine....
     

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