Dirt Track Racing, Open or Locked Differential?

[Diplomat_Wagon]

The class I race in is a bone stock "Thunder" series, stock cars, stock drivetrain, stock suspension, D.O.T "P" series tires etc..

We are allowed very few modifications and one of which is being allowed to weld the differential, no Limited slips or spools. Just a straight up welded stock diff.

My track is 3/8 mile clay surface oval track with 80' of track width and a decent bank but nothing extreme.

My personal opinion is that the car I run doesn't really have the power to power through the turn and a locked diff with improper tire stagger will actually hurt my performance.

I just don't have a lot of racing experience and want to set my new car up right.

Any dirt track guys out there?

 

[BHA43]

I say weld it as you go thru the corner the weight comes off the inside rear & a open diff will spin like if you were stuck on ice thus no power to the ground!

 

[jasperjacko]

Is there a rule against a shorter leaf set on the drivers side to move the left end of the axle forward an inch to help it turn better. I don't know just a thought. I would also think you want 2 tires biting, but welded up might hurt turning. I'm sure there's plenty of setup to fix that though.

 

[Diplomat_Wagon]

I was thinking of offsetting the diff on the spring perch, since I'm eliminating the ISO setup at the back and the spring perches have three holes in them so I could offset the diff on the springs without having to modify anything since I'm not modifying anything I'm just putting it together wrong.


Here is an excerpt from my rules.

FRAME AND SUSPENSION
Stock suspension only for year, make and model of car. All replacement parts must be stock
replacement parts. No modifications or exchanging parts between makes and models allowed unless for
safety reasons.
Stock mounting location for shocks. Only one shock per wheel. No racing shocks. No stock mounting
racing shocks.
Stock location for springs only.
Anti-sway bars cannot be adjustable and must be equally spaced side to side.
Body bushings must be stock.
Front alignment may be set to driver's preference, but no modifications are allowed to any part to
improve alignment over stock adjustment.

DIFFERENTIAL
Must be stock unmodified differential for year, make and model. May be welded. No spools allowed.
No locked, limited slip or posi-traction units allowed. The gear ratio must be a stock ratio for that year,
make and model.

 

[Mroldart2u]

You will want it welded....

 

[Mroldart2u]

Well D_W what did you decide?

 

[Mroldart2u]

I never have figured out why they dont allow a spool, (Tracks around here are the same way) its no gain vs welding. It just does away with the spyder gears and the cross shaft.End result is exactly the same. Locked together axles...