I Would Like To See More Tech .can Leaders Edge Explain Bird
Cage Timeing? Is There Ever A Time To Lead Or Lag The Top Or
Bottom? Dreaed Word Late Models Do Not Run Straght Up.
Birdcage timing is one of those things that is driver/team specific.
The text book way of doing it is that the center of the of the top radius rod bolt and the center of the bottom arm bolt run 180 degrees of each other and intersect through the middle. Guys used to use plumb bobs to check for accuracy and that is why cages have bubble levels in them.
The cars rear geometry basically connects to the birdcages and as the car travels up and down, it travels in an arc and by being level on both sides the car travels in basically an identical arc without binding up.
As long as there have been these types of cars, there has been the argument of what is the best way for it to be done. Some people like them level and some like the RR top to be rolled forward. Just yesterday Steve Stapp was in here discussing basically the same thing and he said that when he drove,they would leave the RR top radius rod nuts loose and reach out twist rod and rock the cage forward during a race, but today he said he likes it more level.
I know several guys who run the RR forward, but I know others who run well who don't.
Late Models use a ton of rear steer, but they also use a driveshaft w/u-joints on both ends. A sprint car uses basically a fixed driveline that limits such motion. Sprint guys used to use open drivelines and torque arms, but when they broke they destroyed guys legs.
I'm sure guys like Coons,Tracy Hines,Briscoe and Stanbrough all have their opinion and I know it is probably more reliable than mine since I have never driven. I can tell you what it looks like, but I don't know what it feels like.
I had some pretty good results early on last year running +2 degrees forward on the LR and +1 degree on the right. I didn't just crank it in on the radius rod though. I squared the rear using our usual method of leveling the frame, and getting the rear end center and square using the jacobs ladder location as the determining factor for driveline length.
I leveled the cages first and then added my degrees with turns on the radius rod. Lastly I adjusted the arm length to make sure they went together free, and hooked up the arms. By doing it this way the rear stayed centered and square with no binds but had the timing in the cages. If I had just cranked on the radius rods the rear would have been bound up. The car seemed to have pretty good forward drive with this setup. The driver I was working with liked the car a little tight so that is why I opted for more left rear timing to give a little more left rear drive. Seemed to work ok.
IT depends on what blocks you use to time the birdcages too, gentlemen.
6"--6.5"--7"--7 15/16" WHATEVER. It makes a huge difference in timing when the car is on the ground with the wheels on it, at say, 14" of stagger vs. 8" of stagger.
People will more readily accept your ideas if you tell them Benjamin Franklin said it first! :thumb
When arguing with a woman: You must first throw out logic and common sense.
Benjamin Franklin :headbang
Im new to midget racing and am having problems timing the cages. I used 6" blocks to time the cages at 90 degrees. When i set my ride hights at 4" the bridcages are now angled back. Is this correct or should birdcages always be at 90 degrees. So i guess what im asking is do i set the cages to 90 when i change my ride height.
I'm just going to read, this is going to get interesting, really, I hope it's not too big of a can of worms, and everyone understands, a lot of it will be conjecture, some will be opinions, some will be factual, some will be what I wish I had tried, and I've heard from Stapp, long ago, and he wasn't the only one, about adjusting them on the fly. Carry on! Bob
"Being old, isn't half as much fun, as getting there"! Ole Robert I!
