When to redo blower??

Discussion in 'Manton Push Rods Top Alcohol Tech Questions' started by dragster156, Nov 27, 2018.

  1. dragster156

    dragster156 Member

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    Curious what and when do people do to freshen their blowers other than new stripping.

    If the blower still makes boost do you just keep running it? ie made 36 lbs of boost all year and never fell off.

    Do you send back to manufacturer of the blower or is their a go to guy who most use that does very nice general work without getting pricing out of control?

    What options, if any, are there for improving a blower.

    any thoughts and opinions welcome. thanks
     
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  2. jay70cuda

    jay70cuda Member

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    I was always told to that if you backfired it or knocked the burst panel out of it , you need to get it restripped. But if you have a good fuel system and lube your blower daily you should be good to go for a while.
     
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  3. Mike Canter

    Mike Canter Top Dragster

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    If the burst panel goes or it back fires then rotate the blower by hand without a belt on it. If no tight spots then most likely the blower is still good. As far as redoing the blower depends on how the car is running, what type of racing and if you use Prizm on it. If you are a car that is running heads up then you probably want the blower redone more often. A bracket or index racer might redo the blower in the off season. There are lots of great guys out there that can go thru the blower and recondition it, Mike Janis, Darren Mayer, Hammer Blowers, Fowler Engines, Littlefield, Gerdot just to name a few great ones.
     
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  4. andy wilfong

    andy wilfong Member

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    As mike says, depends on what type of racing your doing, and what you want to accomplish, if you have a monitoring system on boost and it’s the same at the hit and on the big end and your happy with performance, why restrip it?, on the other hand, if it’s been awhile since being looked at, sometimes we can see a problem developing before it gets expensive, a std restrip with seals and everything from us at Littlefield’s is usually $400, now if I see a problem that would cost you more, we will call you and discuss what it may need, any help I can give you feel free to call me.
     
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  5. dragster156

    dragster156 Member

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    Good info - never backfired or blew out the burst panel and the blower has not moved as far as boost all year. Maybe a few lbs over the entire year but that would be picking up a lb or so in very good air??

    And yes its mostly a dial in car so every inch of performance is not needed. I have seen people have their blowers redone and pick up huge - I assume they were pretty wore out?

    will weigh all options and try to learn more about all aspects as this is the first year running a blown motor.

    thanks for the replies
     
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  6. Mike Canter

    Mike Canter Top Dragster

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    Just to help you figure out if you need more boost or not. One pound of boost can give 100 to 180 hp depending on the engine. The high end being NHRA Promods at that is why they run Al Billes, Mike Janis, Chuck Ford and Hammer blowers and spend $$$$ on them. If you don’t run the latest version of those blowers then you are wasting your time running.
     
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  7. SoDak

    SoDak Active Member

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    Are you sure about 100-180 HP/psi?

    Once on the dyno we upped the OD by 25%, went from 18 to 27 psi and picked up 150 HP at the flywheel. That's about 17 HP/psi
     
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  8. Mike Canter

    Mike Canter Top Dragster

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    If you up the OD to out of the blower design limits you will not gain hp. By increasing OD it takes more hp to turn the blower and also generates more heat. I am talking about increasing boost within the designed OD of the blower. You also have to correct the fuel tuneup to the increased boost. I can tell you for sure that my figures are correct if within the design specs of the blower
     
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  9. andy wilfong

    andy wilfong Member

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    Boost isn’t always power if it creates more heat and the overdrive makes the blower less efficient, there’s a lot to be said for openings and overdrive besides other factors in today’s blowers
     
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  10. SoDak

    SoDak Active Member

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    Yep, we had the tuneup.
    Please explain the "design specs of the blower"?
    I have blower dyno data on our blowers if that helps
     
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  11. Mike Canter

    Mike Canter Top Dragster

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    Blowers are designed to run at certain OD’s. This involves the size of the top opening and the design of the shoe insert in the top. If you have a blower that has been setup for 16% OD and change it to a higher OD then the boost will fall off. People like Mike Janis or Al Billes or other blower guys spend a lot of time designing their blowers to run at specific ODs. Boost pressure is not as important as air flow
     
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  12. dragster156

    dragster156 Member

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    To sound like a real dumbass - what is it that really makes one blower so much better than another. Is it the rotor design? not that I expect every answer in the book but what makes one blower that costs 30-35k spun 16 over so much better than a off the shelf that is spun at 30-32 over and makes much less power?
     
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  13. Mike Canter

    Mike Canter Top Dragster

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    Different OD ratio’s change the characteristics of the incoming and outgoing airflow such as angle. To optimize this the inlet and outlet design are modified to match these characteristics. These modifications really make a big difference and are well worth it. What you are paying for is the R&D effort made by these guys.
     
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  14. SoDak

    SoDak Active Member

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    Our blowers are designed for 35-45% OD and that's where we run them. If you go to a higher OD they have a different inlet for that.

    Mike are you saying if we don't change our OD but make a modification to the blower/hat/intake/heads and the boost changes by 1 psi its 100-180 HP? (please be patient with me I'm just trying to understand)
     
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  15. rpt

    rpt New Member

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    Just a stupid question. You always talk about OD but I think the number to check should be the actual RPM of the blower. 16% OD on a 10k revving engine are quite different from 16 on a 8k revving one. Am I wrong?
     
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  16. SoDak

    SoDak Active Member

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    Its not a stupid question its a great question and absolutely true
     
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  17. Mike Canter

    Mike Canter Top Dragster

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    SoDak you are talking two different things. Boost is a measurement in the intake manifold based on what is not being used so if you change the heads or bigger valves then more airflow and boost will drop. I am talking about blower modifications only increasing boost. Not increasing OD because doing that increases the amount of HP needed to drive the blower and the increases the heat generated by increased friction within the blower. As far as running 16% over drive you are most likely running NHRA promod and you are spinning that motor above 9500 rpm. No NHRA blower would only be spinning the engine to 8800 rpm. There is no such thing as a stupid question.
     
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    Last edited: Nov 30, 2018
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  18. noiraude

    noiraude Member

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    hello Mike
    just bought a whipple screw blower from an alcohol F/C team here in Europe.
    i guess they are running much better heads than those on my engine(old BAE fuel heads):
    so by using heads with less flow, i should see boost numbers higher than those provided by the seller,but making less power?
    are there proven ideal head/blower combinations(at a given OD)?
     
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  19. Mike Canter

    Mike Canter Top Dragster

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    The best heads are the Noonan Mach 1 heads with the big valves since you have a whipple. Yes your boost will probably read higher on those BAE heads depending what heads the previous owner of the Whipple had
     
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  20. SoDak

    SoDak Active Member

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    Ok sounds good, if I mod my blower and gain a psi I should expect at least 100 HP gain, got it, thanks
     
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