The Road to Drag Week 2014 - May 11

[LuxurySportCoupe]

Please tell me that it's going into your Galaxie 

[jayb]

That was the plan, but to be honest I'm not sure the chassis could take the power.  The turbos are sized for 1000 HP each.  That is one of the reasons the project is stalled; I don't really have a good car to plunk the motor into, at least not yet...

[turbohunter]

I don't really have a good car to plunk the motor into, at least not yet...

I have a few in my driveway

[cobracammer]

LOL  I don't know how I would react to the sound of a Cammer engine with the whistle of twin turbochargers.....  I am sure I would lose control of all body functions (For safety, I may have to watch that while standing in a kiddie pool)

[rockittsled]

That was the plan, but to be honest I'm not sure the chassis could take the power.  The turbos are sized for 1000 HP each.  That is one of the reasons the project is stalled; I don't really have a good car to plunk the motor into, at least not yet...

Heh, heh, heh.  You have a Ford GT, why not make it into a real fast, FE powered, GT   

[Dave427SOHC]

I seen a couple on youtube  heres one Jay  https://www.youtube.com/watch?v=yVwzXeAtEHg

Thanks Dave, that is one of Bill Conley's videos.  Probably one of my heads, too LOL!  I've seen most of those.  I thought Doug meant he saw one where the valve head was moving around, so it would have had to have been taken on a spintron machine, looking up into the bore towards the combustion chamber.  Something like that would be very interesting to see...

Ha I need to research here a little more, I was Figuring you hadnt seen them as you just are to damn busy!! HAHA  But as i think about how can you not... I watched about 5 vids theres one that you can see the head of the valve Move (wobble) pretty darn good I puckered up in my seat waiting for the failure... Thank God it didnt happen. keep up the good work Jay

[mike7570]

interesting, I didn't know the valve stems could wobble this much.

https://www.youtube.com/watch?v=_REQ1PUM0rY

[Qikbbstang]

I'm patting myself on the back for questioning on May 14th the strobes frequency giving the impression the springs are oscillating in ways they may not be at all.
Reading the comments on the video link provided by "mike7570" just above, I noted this comment where the poster stated things it a bit more clearly ( I admit I needed to search : Shannon's Sampling Theorem  and Aliasing happens.

 "What you see there maybe it's not what really happens. Have you taken in mind Shannon's Sampling Theorem for this video capture? You may see frequencies that don't exist at all. Aliasing happens. 
Shannon's Sampling Theorem"

Here's a 4-valve 14,000 rpm BMW inside the chamber view that further shows how the strobes speed/revs can fool you.

https://www.youtube.com/watch?v=vcyT18qk8ls

[turbohunter]

Interesting.
Though I totally get the strobe effect in timing, for instance in the BMW vid the strobe obviously was timed when then valves were seated at higher rpm, in the other vid it still shows irregular valve movement like the wobble.
Like using a vacuum gauge for tuning, it's just a tool that is a piece in the total picture.

[WConley]

With the strobe set to the proper frequency, the sampling effect goes away.  In the above videos, you're seeing strange effects because the strobe frequency is not keeping up with the cam rpm.  As the cam rpm passes an "order" or multiple of the strobe frequency, you see things going backwards, then slow to a stop, then move forward.  In that BMW video, it looks like the strobe just hit a maximum frequency and couldn't move higher to keep up with the cams.

On all of my videos I timed the strobe carefully with the cam rpm and filmed at steady-state speed.  This eliminated strange sampling effects.  As long as the motion is well repeated, you'll get a true view when you do this.