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28's vs. 275

Any rear suspension

Any engine

Any power adder

No wheelie bars

275 drag radial or 28 X 10.5 no w

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mx275 Rules

Updated 4/3/2014

Format:

* This is an 1/8 miles heads-up class run on a .400 pro tree with pro ladder. MX275 top 16 Qualifiers will run in the "Front Runner" class. If we have 8 or more cars that did not qualify in the top 16, we will have a "Second Chance" race.

Safety:

* All NHRA/IHRA and local track safety rules apply for driver and car, including the use of an oil retention device or an engine diaper is mandatory.

Chassis:

* Complete stock chassis and front frame rails must be retained from motor plate/shock tower to behind the rear wheel opening. (For non back-halved cars only.)

* Back-halved cars permitted.

* All aftermarket front suspension components allowed.

* All replacement parts must be in stock location.

* Aftermarket bolt-on replacement front K-members/sub frames are allowed.

* Struts or relocated shocks are permitted.

* All aftermarket bolt-on front ends are legal.

* Mini tubs allowed

* Anti-sway bars allowed.

* Relocation of rear shock allowed.

* Rear leaf springs, springs, shocks, and coil-overs may be moved to accommodate tire clearance, and do not need to be mounted in stock location.

* Stock suspension, ladder bar, and torque arm only.

* Aftermarket 4 links prohibited.

* Absolutely no wheelie bars.

* Factory wheel base must be maintained.

Interior/Body:

* Factoring appearing (after market parts are allowed) interior is required.

* Factory floor pan on driver and passenger side required from firewall to rear of door jamb.

* Firewall must be in stock location, minor modifications for trans, etc. are fine.

* Head-lights and tail-lights must work.

*Aftermarket fiberglass or carbon fiber replacement panels will be limited to hoods, front fenders, doors, deck-lids, and bumpers only. All front ends must be factory appearance and cannot be stretched.

* No extenders or stripe takers

* Lexan allowed, must maintain factory appearance.

Engine:

* Maximum displacement for all engines is 640 c.i.

* Small blocks are allowed any deck height, but must remain stock bore spacing.

* GM Big Blocks are limited to 10.2 deck height.

* Ford Big Blocks are limited to 10.3 deck height.

* Mopar Big Blocks are limited to 10.7 deck height.

* Billet blocks are prohibited for both SB and BB combinations.

Transmission:

* Any transmission permitted.

Turbochargers:

* Single turbocharger limited to 88mm maximum. (GT55-88, Pro-Mod 88, ET-R88, Comp, Bullseye or = mid frame turbo.)

* Twin turbochargers limited to 72mm maximum.

* Turbo size will be verified by measuring the housing bore at the leading edge of the impeller wheel and must maintain the contour of the compressor housing.

* Inducer dimensions will not exceed 3.462 inches and exducer dimensions will not exceed 4.765 inches on mid frame turbos. Inducer dimensions will not exceed 3.462 inches and exducer dimensions will not exceed 5.56 inches on Large Frame turbos.

* The maximum diameter of the housing bore at the leading edge of the wheel may not exceed 2mm more than the maximum allowable.

* Inserts or reducers to achieve inlet or outlet dimensions are prohibited.

* Any type of air to air or water to air intercooler is permitted.

* Turbochargers with nitrous oxide is permitted only on 2-rotor, 4 cylinder, and inline 6 cylinder engines.

Superchargers:

* Cog or gear driven superchargers are permitted, must meet all factory inlet, outlet, and internal housing dimensions.

* Inserts or reducers to achieve inlet or outlet dimensions are permitted.

* Any type intercooler is permitted.

* F-1R or equivalent allowed

* F-2 or equivalent allowed

* F-2R is not legal.

* Big Block with single F1R or F1X/F2 supercharger must have a 3.875 reducer.

* Cannot combine the supercharger with nitrous.

* Roots supercharger limited to 10-71.

* Centrifugal superchargers are permitted.

* Screw Superchargers (PSI C or D Rotor, and Whipple A980 or R980,etc.) are prohibited.

* No Methanol cooling on blower or turbo combos running E85 or alcohol.

Nitrous (General Rules):

* Multiple bottles, must Y together to a single #6 line.* Push nitrous systems are prohibited.

Small Block Nitrous:

* Permitted to run any multi-stage nitrous system.

Big Block Nitrous:

* Multiple Nitrous kits, must use #4 Nitrous line maximum, minimum 12 inches long attached single side of Y or at single bottle.

* Electronic Fuel Injection allowed only 8 nitrous feed lines on engine.

* Two Stage Plate allowed.

Exhaust:

* Mufflers or inserts are required on all cars except for turbo cars.

* Exhaust may exit underneath car or out the front fenders, but must not affect timing or staging beams.

Fuel:

* Gasoline, Alcohol or E-85 is allowed.

* No Methanol cooling on blower or turbo combos running E85 or alcohol.

* Alcohol must adhere to a 50 lbs. weight penalty.

* Alcohol when used in conjunction with intercoolers must adhere to a 50 lbs. weight penalty.

Tires:

* All cars with power adder must compete on a Drag Radial type tire with the following sidewall designation 275/60/15.

* Naturally aspirated cars are permitted to run a 28.0" x 10.5" slick, no "W" tires permitted

Minimum Base Weights (All minimum weights include the driver):

General:

* Small Blocks (NOS and N/A) with single 4150 carb/throttle body: deduct 50 lbs.

* Small Block (NOS) with any plate nitrous system: deduct 50 lbs. (deduct does not apply if used in conjunction with fogger)

*Small Blocks (NOS and N/A) with 23 degree Chevy heads, 20 degree Ford heads, and 18 degree Mopar heads: deduct 100 lbs. RR-75 lbs.

* Small Blocks (NOS only) 18-10 degree valve angle inline head: deduct 50 lbs.

* Small Blocks (NOS only) cast t-ram/sheet metal/2 carbs or 2 throttle bodies: add 50 lbs.

* Throttle Bodies exceeding 4500 series on Big Block combinations: add 50 lbs.

* Non-Intercooled boosted cars on gasoline: deduct 50 lbs.

* Belt driven centrifugal superchargers: deduct 50 lbs.

* Deduct 250 lbs. Front Wheel Drive

* Deduct 25 lbs. Leaf Springs

* Deduct 300 lbs. for Inline 6 Cylinder Turbocharged/Supercharged/Nitrous Combos

* Deduct 150 lbs. for V-6 Turbocharged/Supercharged/Nitrous Combos

* Deduct 800 lbs. for 4 Cylinder Turbocharged/Supercharged/ Nitrous Combos

Small Block:

* Naturally Aspirated...2350 lbs.

* Nitrous... 2600 lbs.

* Single YSI/F1A/6-71 Supercharger...2800 lbs.

* Single F1C/8-71 Supercharger...2900 lbs.

* Single F1R/Xi/10-71 Supercharger (mod motor with stock angle valve heads)...3300 lbs. (add 150 lbs. for billet Xi)(deduct 50 lbs. for 8.2/8.7 deck)

* Single F1R/Xi/10-71 Supercharger (any cylinder head)...3100 lbs. (add 150 lbs. for billet Xi) (Deduct 50 lbs. for 8.2/8.7 deck)

* Single F1X/F2/XB105 Supercharger (mod motor, LS 15 or with stock valve angle heads cast head only)...3250 lbs. (deduct 50 lbs. for 8.2/8.7 deck)

* Single F1X/F2/XB105 Supercharger (inline head - SB Mopar SVA Hemi - C3/SB2)...3300 lbs. (deduct 50 lbs. for 8.2/8.7 deck - no deck ht. deduct for C3)

* Single F1X/F2/XB105 Supercharger (non-inline cast head)...3400 lbs. (deduct 50 lbs. for 8.2/8.7 deck)

* Single 76mm T6 Turbocharger (mid frame)...2700 lbs.

* Single 80mm T6 Turbocharger (mid frame)(add 150 lbs. for GT55-80)...2800 lbs.

* Single 82mm T6 Turbocharger (mid frame)...2900 lbs.

* Single 83mm T6 Turbocharger (mid frame)...2950 lbs.

* Single 85mm T6 Turbocharger (large frame 85/ GTX55-85)(non-inline head)...3200 lbs. (deduct 50 lbs. for 8.2 deck)(deduct 50 lbs. for inline cast head)

* Single 85mm T6 Turbocharger (Pro Mod 85)...3250 lbs. (deduct 50 lbs. for 8.2 deck)(deduct 50 lbs. for stock valve angle)

* Single 88mm T6 Turbocharger (Y2K or GT47-88) (mid frame)...2950 lbs.

* Single 88mm T6 Turbocharger (large frame 88/GTX55-88) (small block - mod motor or stock inline-valve angle cast head)... 3300 lbs. (deduct 50 lbs. for 8.2 deck)

* Single 88mm T6 Turbocharger (large frame 88/GTX55-88) (small block - any head)... 3350 lbs. (deduct 50 lbs. for 8.2 deck)

* Single 88mm T6 Turbocharger (PTE ProMod MF88) (mod motor with stock valve angle cast head only)... 3350 lbs. (deduct 50 lbs. for 8.2 deck)

* Single 88mm T6 Turbocharger (PTE ProMod MF88) (cast head only)...3400 lbs. (deduct 50 lbs. for 8.2 deck)

* Twin 67mm Turbochargers...3200 lbs.

* Twin 72mm Turbochargers...3250 lbs.

Big Block:

* Naturally Aspirated...2600 lbs.

* Nitrous-two stage plate any deck height (up to 604 c.i.)...3100 lbs.

* Nitrous-standard deck height (up to 604 c.i.)...3250 lbs.

* Nitrous-tall deck height (up to 604 c.i.)...3300 lbs.

* Nitrous-any deck height (605 to 640 c.i.)...3350 lbs.

* Single F1R/Xi/10-71 Supercharger...3400 lbs.

* Single F1X/F2/XB105 Supercharger...3450 lbs.

* Max 88mm Single Turbocharger...3400 lbs.

* Max 72mm Twin Turbochargers...3350 lbs.

Buick/Olds/Pontiac:* Nitrous Combos will not exceed 640 c.i. and must be 3200 lbs.

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