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General control line discussion => Open Forum => Topic started by: Paul Taylor on January 13, 2012, 07:11:20 PM

Title: 89000 RPM !!!! Strap this puppy on
Post by: Paul Taylor on January 13, 2012, 07:11:20 PM
http://www.youtube.com/watch?NR=1&feature=endscreen&v=N3sHZL798ng

Title: Re: 89000 RPM !!!! Strap this puppy on
Post by: Clint Ormosen on January 13, 2012, 07:40:26 PM
I can't see the decimal point on the tach, but I'm pretty sure it's not 89,000 rpm. In my R/C boat days, a K&B 7.5 inboard would rev >35K and the in-line 4 in the video didn't even sound close to that.
Title: Re: 89000 RPM !!!! Strap this puppy on
Post by: Paul Taylor on January 13, 2012, 07:53:33 PM
O

So how bout that engine. Never seen a 4 banger. Think it is a home built?
Title: Re: 89000 RPM !!!! Strap this puppy on
Post by: Randy Ryan on January 13, 2012, 08:46:47 PM
O

So how bout that engine. Never seen a 4 banger. Think it is a home built?

My guess it he built it up using some factory liners and pistons.

Another thing, at 89K RPM he probably would have have a prop blade stuck through him!

Here's an I-6

http://www.youtube.com/watch?v=gpPdZ3KRGBg&feature=related
Title: Re: 89000 RPM !!!! Strap this puppy on
Post by: Marvin Denny on January 14, 2012, 09:23:36 AM
  Perhaps it is me, but it looked to me that he had his tach set for four blade prop when he showed the RPM???  That would definitely throw off the reading wouldn't it??

   That sound definitely didn't sound like That high of RPM.
  I Would definitely like to see it in person to believe the 89K+ RPM.

  Bigiron
Title: Re: 89000 RPM !!!! Strap this puppy on
Post by: Mike Greb on January 14, 2012, 09:30:23 AM
I would bet that the first 8 is an artifact of how the camera sees the lcd display, not how the naked eye would see it, i would bet it was actually reading 9000 or so.
Title: Re: 89000 RPM !!!! Strap this puppy on
Post by: Paul Taylor on January 14, 2012, 11:36:52 AM
yea I was a little sleepy when I posted this and the number really made me sit up.

I have the same tach but it has been so long since I used it I could not tell you much about the display.

Looking at it now, I too think at that speed it would have thrown a blade.

Still cool to see these big engines.
Title: Re: 89000 RPM !!!! Strap this puppy on
Post by: John Stiles on January 14, 2012, 11:58:04 AM
Paused it on frame 1:25 and it clearly has 09000  ;)
Title: Re: 89000 RPM !!!! Strap this puppy on
Post by: Steve Helmick on January 14, 2012, 03:24:40 PM
Yup, 9k. Multi cylinders sound really "busy", with alternate firing. It could fire one, two, or four cylinders at the same time. Each setup would have a very different sound, and different vibration, torque and horsepower output.  y1  Steve
Title: Re: 89000 RPM !!!! Strap this puppy on
Post by: john e. holliday on January 15, 2012, 07:54:24 AM
Yes, I would agree that the engine is turning about 9M RPM.  I have the same type digital tach and the has two and three blade settings.  For 4 blade setting with a two blade prop, you have to double the reading.  I know from experience that a three blade setting will give fewer rpm readings. 

A side note,  if you have eye protection on such as sun glasses you may not see the reading on the tach or even the screen on your digital car radio.   I thought my tach was not working until I took my sunglasses off. H^^
Title: Re: 89000 RPM !!!! Strap this puppy on
Post by: John Stiles on January 15, 2012, 10:50:11 AM

A side note,  if you have eye protection on such as sun glasses you may not see the reading on the tach or even the screen on your digital car radio.   I thought my tach was not working until I took my sunglasses off. H^^
LL~ LL~ LL~ LL~ Well, Doc; time to think about getting perscription sun glasses....or get some cataract work done. :## ;D LL~ LL~ LL~