89000 RPM !!!! Strap this puppy on

[Paul Taylor]

http://www.youtube.com/watch?NR=1&feature=endscreen&v=N3sHZL798ng

[Clint Ormosen]

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.

[Paul Taylor]

O

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

[Randy Ryan]

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

[Marvin Denny]

  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

[Mike Greb]

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.

[Paul Taylor]

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.

[John Stiles]

Paused it on frame 1:25 and it clearly has 09000 

[Steve Helmick]

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.    Steve

[john e. holliday]

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.

[John Stiles]

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.

Well, Doc; time to think about getting perscription sun glasses....or get some cataract work done.