Curmudgeon wrote:
The Yamaha kart thing reminded me of another deal I saw many years ago. The 100cc motocross class was big and hotly contested, a lot of the riders had Honda SL100's. The Honda 100 and 125 engines were basically identical except the 100 had '99cc' and the 125 had '123cc' cast into the cylinders, they shared a common stroke but different bore. One guy got a 125 cylinder, heated it till the sleeve came out, then did the same with his 100 cylinder. The finned part of the 100 cylinder was then bored, heated, and the 125 sleeve slipped into it. Voila: a 125 cylinder with the '99cc' casting. But that's not all!
I did something very similar to my 77 YZ 100 with a YZ 125 barrel. I was 15 at the time.
Javelin wrote:
Another is they would check the temperature of the fuel right before the burnout box (chemistry/physics - a colder fluid is denser, which = more power). They would fill the bottom 3/4 of the tank with the coldest fuel they could go and top it off with warmer than minimum. When the NHRA took a pipette off the top they were free and clear.
Or it would be, um, theoretically possible to have a fuel cell with a false floor. Good gas goes down low, legal fuel that gets siphoned and checked comes from up top.
Curmudgeon wrote:
Next chance he gets, my buddy glances over and sees that the rear of the hood is open about 1 1/2". In a turn, it's closed. On the straight, it's open again.
In a similar way, aero came to SS/GT in the late 80's when data logging became available. We discovered that rolling up the side windows on a long straight (like Road Atlanta) just an inch or two changed the airflow into the car enough and was worth eniough MPH to be repeatable and reproducible in testing. Not coincidentally, you could get a 1LE Camaro with power windows.
When American Sedan rules were written, they required a firewall to isolate the fuel cell but didn't clarify. We built a full floor to ceiling wall right behind the driver's seat with a little window in it for rear view to keep all of the air out of the hatch area. Car got balled up before we got to work with that one.
Swank Force One wrote:
Heh, i was unclear. I'm sure something was opening the hood and it probably wasn't terribly hard to do... i'm just saying that there's really no benefit to spacing your hood like that on a Miata. Might help your underhood temperatures a little bit, but will also decrease the efficiency of your cooling system.
Again, not sure about the Miata, but it sure as hell does make an RX-7's coolant temps come down.
People say this and that about the high pressure area at the cowl, but there's also two big low pressure areas along the sides, and there's an engine in the way at the cowl.
It's one of those things where theory can theorize all it wants but in practice it works and that's all I need to know, you know?
Javelin wrote:
. You would "deep" stage the longer front in essence, so the car would only have to run 1319'11", making you quicker without actually being quicker.
I always, always, always shallow-stage. Shallow staging is worth a tenth all by itself because you get 6" or so of runup before your run actually starts, Cutting a good light is down to timing, and if you can time good lights with deep-staging then you can do it with shallow staging.
Variable wheelbase allows you to shallow-stage even further back.
And then there's gaming the rules for engine setback by running an engine with the left front spark plug in a favorable position.
In reply to Knurled:
Yes, shallow-staging is the way to go (says the 2008 track champion... me! 
). The offset wheels allow you to shallow stage the "car" and deep stage the "tire" for the other end. It's pretty berking genius, and whoever did it first must have really had an edge until word leaked out.
There was awhile there when the Pro Stock cars (and others too) had a lower fin reflector thing to trip the finish lights before the wheels (back before NHRA went to the cameras to show the pro class wins).
