A bit more about the teardown...

I just happened across some pictures from our teardown in Chicago that added some things that I didn't capture in Las Vegas..

I talked about the fact that they cc'ed the heads, etc. But unless you see it done, it is a little abstract. So here are pictures and some explanations.

To measure the combustion chamber, they put a piece of plexiglas, with a small opening in it, over the combustion chamber in the head.  They put some substance around the opening (not sure what to call it it) to be sure the plexiglas seals.

Then they take a graduated tube filled with alcohol, and with a spigot to dispense it, mounted on a metal stand, and open the spigot until they fill the combustion chamber with liquid through the aforementioned hole in the plastic, measuring how much liquid leaves the tube.

And they also do a similar procedure on both the intake runner, (that is the part between the intake valve and intake manifold),

 and the exhaust runner........

And that is how they measure these things.....

As mentioned before, they also check how big our piston is, total bore, and how high it goes from the bottom of stroke to top of stroke, for total stroke. But that is pretty easy, and done with a simple dial caliper.

The real interesting, and often most problematic, measurement is the cam lift on both the intake valve and exhaust valve.

First, you need to install a solid lifter in the intake side of a cylinder, and one in the exhaust side of that same cylinder. Oh, you don't have any solid lifters? Of course not! Our car uses hydraulic lifters. So how are we expected to come up with a solid lifter, when they aren't even made for our car?

Simple, take one of your spare hydraulic lifters, dissasemble it, and fill it with washers, that bring it up to height you need, put the top back on, and you have it. So make sure you carry a variety of different thickness washers to use for this purpose. If you don't have spares, you can use on of your running lifters, and then return it a hydraulic when done. But these lifters aren't expensive, and once you get one lifter together, you won't want to take it apart again. So pick up some spares, and have two ready for use in teardown.

As an alternative, you can cop an attitude, and tell the techs that don't have onem and there is nothing you can do. But in my opinion, throwing down a gauntlet is not a good idea. These guys have no agenda, and just want to make sure that you are legal. But if you get snarky with them, or they think you do, at best, they will be just a little more thorough in all of their tests. And one time through is quite enough, thank you.

What makes this measurement interesting is the necessity to get everything exactly perpendiular to valve, and to do this a steel plate (small) is bolted to the head. Then a magnetic mount for a dial indicator is secured on the steel plate. Then the dial pointer is placed on the top of the spring retainer. And this is all done while the head is on the block, and bolted down.

But, this is place where if the dial indicator is not perpendicualr to the valve, an error in the reading can be introduced. And frankly, it is hard to get it all lined up properly. If you have been cooperative and haven't upset the techs, you can gently help them see if they aren't lined up right.

As you can, there is an awful lot to getting torn down, and there are specifications for all of these things, and more. Like the wheelbase of the car. And the height of the front end of the car, and making sure that the drive shaft is steel, and the center section of the rear end is steel. (except in the case of the 2011 V10 Challenger which can be aluminum.)

And I never mentioned that when we are getting "teched in" at any track, they check the brand,  the SFI rating,  and the expiration date on the seat belt harness, and the racing suit (pants, and jacket) and the helmut.

Rules, rules, and more rules. All intended to promote safety, and to assure a level playing field.

God Bless, and Race Safely

And mostly, have a wonderful Thanksgiving, and tell everyone you love, that you love them!

David