Pure Stock 4's
2020 Pure Stock 4's Rules
1. Rear wheel drive only. Max. wheel base 104”.
2. Stock firewall and floor pan in stock location.Or steel in stock location replaced for repairs.
3. Stock bodies and after market bodies and noses Ok, must be stock appearing bodies and track approved,May use stock tail piece or 12"min tall aluminum to close in rear. 6in spoiler ok.
4. 3 bars in front of driver or screen to protect driver from rocks, etc.
5. OEM transmission with all gears in working order.
6. Stock or stock replacement clutch and pressure plate. Stock flywheel, must weigh 16 lbs. No scalloped flywheels.
7. Roll cage: Min 1 ½” x .095 steel full roll cage. 8 Anchor points recommended and must be secured to unibody. Must be track approved.
8. 4 driver door bars, at least 3 bars in right side door, all major stress points are to have gussets.
9. Stock chassis, may tie chassis together. Engine must mount in stock location, with NO setback.
10. Brakes: May have racing pedals with any master cylinder. No adjustments with all four wheels to have working brakes. No drilled rotors or lightened drums.
11. Suspension: Stock struts and Any steel non-adjustable steel shock, Caster and camber plates allowed, no screw jacks,Adjustable cups and shackles allowed and factory pan hard bars only. Top shock mounting point may be relocated.
12. Drive shafts: 1 ½” OD minimum. Steel only. Must be painted white.
13. Rear-end must be stock up to a 9in for make of car. No lightening allowed. May use mini spool, or weld rear-end. Axles must be stock.
14. Stock steering components."Steering quickners OK"
15. Any steel wheels up to 8''. Large wheel studs OK. Bead locks allowed on right side....Any 60 or 70 series DOT street tire 13”, 14”, or 15” untouched. NO racing tires of any type. (NO American racers or Hoosiers) No soaking, grooving or siping, Must punch 60 ***Note*** May run Towel City Retread Mini Stock/legend DOT Stamped 205/60/13 (89 compound) Must punch 60.
--------Pure Stock 4 Engine Rules----------
1 lb. per c.c. as measured. Minimum weight 2000 lbs. after race with driver.
Weight must be marked on hood or front fender near driver.
4 cylinder OEM block only. Wear tolerance will be allowed.
OEM intakes only.
Stock cast iron manifolds or header with ($150 claim rule.....NO TRI-Y's)
Stock crank, stock stroke NO lightening. Rods: ANY steel rod.....
Pistons:Any flat top Toyota: 3TC may run dome .267, 20 and 22 may run dome .125 NOTE: Zero deck height.
Carburetor: Stock 4 cyl. carburetor for make of car or Holley 350 CFM (#7448) Must have air horn with number. 1” thick maximum adapters allowed with 2 gaskets only @ .070” max or 1 stock gasket without adaptor. Holley 350 CFM Venturi and Base measurements must remain factory.
Cam: Max lift 425" lift,no rollers checked with .025" lash( hydraulic or solid ok.)
OEM oil pumps only.
Valves: steel only, no hollow valves, stock diameter. Valve springs: single or double allowed, must be steel.
Any steel retainers allowed.
Ignition,Must be stock type distributor and coil. May use Mel’s ignition. No aftermarket multiple spark or adjustable electronic type systems allowed. No traction control.
Head, Must be stock OEM, absolutely no porting or polishing allowed. No extrude honing allowed. No acid porting allowed. Ports must remain at factory OEM shape and volume. Head may be angle cut. A bowl cut is allowed but,
cannot exceed the ID of the valve seat and can be no deeper than the valve guide. Bowl cut must be concentric with the valve guide.