2002 IMCA - TYPE MODIFIED

NOTE: THIS IS AN OPTION TO RUN IMCA  TYPE MODIFIED.

For rules and regulations for IMCA-Type Modified, refer to a current IMCA Rule Book along with the following changes:

CLAIM RULE
1.$500 claim or trade on engine (from oil pan up to, but not including, carburetor) among IMCA-Type Modified cars only.  See IMCA Rule Book for a detailed list of what is or is not included with claim.
a.Must finish in top 4 in "A" feature to be claimed.
b.Claims must be made by driver wishing to make claim within 10 minutes after "A" feature to technical inspector in writing and with cash.
c.Driver making claim must be in top 10 finishing position with an operating car in same feature to make claim.
d.Driver must accept claim or agree to trade within 10 minutes of claim.
e.Refusal of claim or trade will result in suspension from this division for 1 calendar year.
f.Driver must take responsibility to remove engine for claim or trade that night in a timely matter.
g.The first decision to accept or not to accept a claim will be final.
h.Only 4 engine claims can be made in a season per driver.

WEIGHT
1.Minimum total weight is 2500 pounds after race with driver.
2.Maximum left side weight is 58% of total weight.
3.All ballast must be in block form of five pounds minimum, painted white, have car number on it, and be securely fastened.  A FINE OF $5.00 PER POUND WILL BE ASSESSED FOR ANY LEAD FOUND ON THE TRACK.
4.Weight penalties may be added to any car not meeting rule requirements.

EXHAUST
IMCA legal mufflers required.

SUSPENSION / STEERING COMPONENTS
Spindle steering arms and OEM drag link may be drilled to accept spherical type tie rod ends.

TIRES
3.IMCA-Type Modified cars will run the IMCA legal treaded tire.

MISCELLANEOUS

1. Radio communication is permitted.
2. .A scanner that is programmed to receive the track frequency is required.

2002 MIDWAY SPEEDWAY MODIFIED

GENERAL DESCRIPTION

2500 pounds, 56% left side weight, aluminum/fiberglass body, open wheel, 350 CFM 2-barrel carburetor, 11.0:1 compression ratio,  stock frame.  No wide 5 wheels.

ELIGIBLE MODELS

A) BODY
a.Only 1970 or newer American passenger cars permitted.  No panel vans or station wagons.
b.Bodies must be symmetrical in size from side to side and from front to rear.
c.Must use full stock appearing roof with stock appearing roof support and window pillars.   Half roofs are not permitted.
d.Roof width: 44 inches min.: 50 inches max.
e.Roof length: 41 inches min.: 56 inches max.
f.Interior slope is 4 inches maximum front to rear.  If front half of interior is flat, 50% of the 4 inches is already used.  Therefore, only 2 inches of slope is permitted from behind driver to rear.
g.Hood may have side panels with a maximum height of 4 inches and must be enclosed at rear.
h.Engine compartment must have completely open sides.  Front wheels must not be covered.
i.Passenger side of body must be no further forward than rear of block..
j.Quarter panel length, measured from centerline of rear axle to rear of bumper, is 34 inches minimum and 45 inches maximum.
k.Left rear tire must extend 1/2 inch minimum outside of body at closest point.
l.Rear of car must be completely sealed between quarter panels and bumper, with a minimum rear deck panel height of 8 inches.
m.Rear deck width, measured from outside to outside of quarter panels at widest point, is 53 inches minimum and 66 inches maximum.
n.Rear deck height is 28 inches minimum and 38 inches maximum.
o.Bumpers must be used both front and rear.  2 bar front bumpers must be mounted frame end to frame end with bottom loop parallel to ground.
p.No rear spoiler permitted.

B)WINDOWS
a.Must be equipped with a full lexan windshield curved to contour of roof which is sufficiently braced.
b. Glass/lexan installed in door windows not permitted.

C) INTERIOR
a.Must have full floorboards.

WEIGHT

1.Minimum total weight is 2500 pounds after race with driver.
2.Maximum left side weight is 56% of total weight.
3.All ballast must be in block form of five pounds minimum, painted white, have car number on it, and be securely fastened.  A FINE OF $5.00 PER POUND WILL BE ASSESSED FOR ANY LEAD FOUND ON THE TRACK.
4.Weight penalties may be added to any car not meeting rule requirements.  50 lbs. penalty for running dry sump system.

ENGINE

A) ENGINE LOCATION
a.Rear of engine (bell housing flange) must be 72 inches minimum from centerline of rear axle.
b.Centerline of crankshaft must be laterally located within 2 inches of the midpoint of a line projected between centerline of upper ball joints.
c.Centerline of crankshaft must be located at least 10 inches above ground plane.


B)ENGINE SIZE AND CONFIGURATION / ENGINE  BLOCK
a.Maximum of  358 cubic inches, any bore, any stroke, NO TOLERANCE.
b.Only standard cast iron engine block permitted.
c.No after market engine block permitted.
d. Maximum compression ratio 11.0 : 1.

C) OIL PAN / OIL SYSTEM
a.Dry sump system not permitted.  If dry sump system used, an additional 50 lbs. will be required.  External oil pump not permitted.

D)CYLINDER HEADS
a.Only unaltered stock cast iron production heads limited to 2 valves per cylinder permitted.
b.No port matching or flow work of any kind permitted.
c.No angle cutting of heads to block mating surface permitted.
d.No offset drilling head stud or bolt holes permitted.
e.3 angle valve job permitted.
f.Combustion chamber may be polished.
g.Chevrolet part number 14011058 and 10134392 (casting number 14011034)
head or any cast iron OEM head permitted on GM block.
h.Chrysler W-2 cast iron heads permitted on Chrysler block.
i.Any Ford stock production cast iron heads permitted on Ford block.
 j.Only steel valve springs permitted.

E) VALVES
a.Must be identical in appearance and construction as OEM.
b.No air directional devices on any of valve surface permitted.
c.No titanium valves permitted.
d.Valve stem diameter is .34375 inch (11/32 inch) minimum.
e.Undercutting valve stem diameter from head of valve to bottom of valve guide is permitted; .3125 inch (5/16 inch) minimum.
f.Maximum valve sizes as measured across face of valve are as follows:

              INTAKE EXHAUST
General Motors  2.020  1.625
Ford "Windsor"              1.8437   1.546
Ford "Cleveland" 2.046  1.656
Ford M-6049-N351 2.020  1.600
Chrysler  2.020  1.625

F) CRANKSHAFT / HARMONIC BALANCER
a.Only steel or cast iron production design crankshaft permitted.
b.After market crankshaft is permitted.
c.Any harmonic balancer permitted.

G) CAMSHAFT / VALVE LIFTERS / ROCKER ARMS
a.Any flat tappet camshaft using solid steel or hydraulic valve lifters permitted.
b.Roller or mushroom valve lifters not permitted.
c.Rev-kits not permitted.
d.Roller rocker arms permitted.
e.Lifters must be OEM diameter for block being used.

 H)  INTAKE MANIFOLD
1.1.  No port matching or flow work of any kind permitted.
2.2.  Must remain as manufactured.
3.3.  Must not be painted.
a.Must use current design intake manifold as follows:

HEAD USEDI    NTAKE PART # INTAKE MANUFACTURER
Chevrolet  2101  Edelbrock Performer Series
Chevrolet "Vortec" 2116  Edelbrock Performer Series
Ford "Windsor" 2181  Edelbrock Performer Series
Ford "Cleveland"
4-barrel  2665  Edelbrock Performer Series
Ford "Cleveland"
 2-barrel  2750  Edelbrock Performer Series
Ford M-6049-N351 M-9424-C358 Ford Performance
*Chrysler  P4529295/cast# 8015 Chrysler
*Chrysler  2176  Edelbrock Performer Series

*On Chrysler intake manifold, welding a maximum of 1/2 inch from bolt on flange surface up into intake port to match the W-2 port design is permitted.  Ports may be welded only.  No grinding or polishing permitted.

I) CARBURETOR
a.Must use Holley 2300, 350 CFM, 2-barrel carburetor, model number 7448, with venturi size of 1-3/16 inches and throttle bore of 1-1/2 inches maximum.
b.Holley 2300 2-barrel carburetor rework guidelines are as follows:
i.Body of carburetor:  No polishing, grinding, or drilling of holes permitted.
ii.Choke may be removed, but all screw holes must be permanently sealed.
iii.Removing choke horn not permitted.
iv.Boosters must not be changed or altered in any way.
v.Venturi area must not be altered in any way.  Casting ring must not be removed.
vi.Alterations to allow additional air to be picked up below opening of venturi such as altered gaskets, base plates, and drilling holes into carburetor will not be permitted.
vii.Base plate must not be altered in any way.
viii.Butterflies must not be thinned or tapered.  Idle holes may be drilled in butterflies.  Screw ends may be cut even with shafts, but screw heads must remain standard.
ix.Throttle shafts must remain standard and not altered in any way.
x.Fuel injection, superchargers, or nitrous oxide not permitted.

J) CARBURETOR SPACER / GASKETS
a.Only 1 piece solid aluminum carburetor spacer, maximum of 3/4 inch thick must be installed between intake manifold and carburetor.
b.Spacer must be centered on intake manifold and have 2 holes with 1-1/2 inch openings located in center that match base of carburetor.  Holes must be cut perpendicular with base of carburetor.  No taper, bevels, or any modifications permitted.
c.Only 1 piece paper gasket maximum of .065 inch thick that matches exterior dimensions of carburetor throttle plate be installed between carburetor and spacer.  1 piece paper gasket maximum of .065 inch thick must be installed between spacer and intake manifold.   Gasket must be no larger than top of intake manifold.

K)CARBURETOR AIR CLEANER / AIR INTAKE
a.A dry type round air cleaner element will be required.  It must have metal top and bottom with a diameter of 12 inches minimum, 17 inches maximum and a maximum height of 4 inches.
b.Air cleaner base must be no higher than top of choke horn.
c.All air must be filtered through air cleaner.
d.No hoses, funneling devices, or devices designed to get more air into engine will be permitted (no carb hat).
e.No air intakes facing forward permitted.
f.No air boxes permitted.

IGNITION / ELECTRICAL SYSTEM

1.Crank triggered or multiple coil ignition systems not permitted.
2.Dual ignition boxes are permitted
3.Onboard electronics such as but not limited to lap timing devices, suspension monitors, computers, torque limiter ignitions, and other electronic devices not permitted.

EXHAUST

1.Headers may be used but must be collector type.
2.Exhaust must exit behind driver.
3.Must be sealed tight and securely mounted.


DRIVE TRAIN

A) CLUTCH / FLYWHEEL / BELLHOUSING
a.High speed multiple discs clutch is permitted.
b.Clutch assemblies must be mounted inside bellhousing.
c.Only steel, heavy-duty cast iron, or after market aluminum bellhousing permitted.
d.Must be capable of being put into and taken out of gear with engine running.
e.Must have a flywheel with a starter ring on it.

B) TRANSMISSION / DRIVE SHAFT / REAR END
a.3 or 4 speed transmission must be OEM production manufactured that is cataloged through regular dealer channels.
b.Automatic transmission is permitted, but cannot use a torque converter.
c.5 speed, internal clutch transmission, or quick-change transmission not permitted.
d.Transmission must have at least 2 forward gears and reverse gear in working order.
e.Transmission must bolt directly to rear of bell housing, which bolts directly to rear of engine block.
f.Only steel driveshaft permitted.
g.Open tube rear end not permitted.
h.Independent rear axles not permitted.
i.Quick change rear end not permitted.
j.Aluminum rear end not permitted.
k.Full floating rear axles recommended.

C) WHEELS
a.Only steel racing wheels with a maximum width of 8 inches permitted.
b.Bead locks not permitted.
c.Wide 5 wheels not permitted.

D) BRAKES
a.Calipers must be single piston cast iron OEM.
b.Only 1 brake line per caliper.  No brake recirculators permitted.
c.Only steel or cast iron brake rotors permitted.
d.Rotors may be re-drilled for different bolt pattern or larger studs
but must not be drilled to lighten.
e.Front rotors and hubs must be OEM.
f.Carbon fiber brakes not permitted.
g.Brakes must operate all 4 wheels.

WHEELBASE / TREAD WIDTH

1.Minimum wheel base permitted is 108 inches.
2.Tread width, measured from outside of tire side wall to outside of tire side wall, is 80-1/2 inches maximum.

FRAME

1.Must have complete 1950 or newer American OEM passenger car production frame with parallel rails.
2.4 wheel drive, pick-up, or sports car frames not permitted.
3.Must not be widened or narrowed at front (except for notching for radiator clearance) and must be able to support main vertical bars of main roll cage.
4.May be cut off 36 inches maximum from rear axle centerline.
5.Front cross member may be altered for oil pan clearance.  Distance between front frame rails must be OEM dimensions.
6.Ground clearance is 4 inches minimum for side frame rails and body components with driver in car.

SUSPENSION / STEERING COMPONENTS

1..All suspension parts must be made of steel.
2.Lower A-frames must be stock production for type of frame and must mount is stock location.  May only be altered for non-stock ball joints, bushings, shock mounts, and sway bar mounts.
3.Upper A-frames may be stock or tubular type and frame-mounting brackets may be relocated.
4.Spindles must be OEM.
5.Spindle steering arms and OEM drag link may be drilled to accept spherical type tie rod ends.
6.Pitman arm and idler arm must be OEM.
7.Weight jacks permitted.  No hydraulic weight shifting devices permitted.
8.Only 1 shock per wheel and 1 shock for lift arm permitted.
9.Shocks must be steel, no aluminum permitted.
10.No adjustable shocks permitted.  Shocks must be sealed units that cannot be disassembled.
11.Coil over shocks/springs not permitted.
12.Coil over eliminators not permitted on front.
13.No adjustable suspension components or weight shifting devices that can be adjusted inside driver compartment permitted.
14.No center steering permitted.  Driver must be on left side of drive shaft.
15.Must have a collapsible steering shaft or use at least
16.universal joints, which are not mounted in same plane.
17.Must use an approved steering wheel disconnect.
18.Rack and pinion steering not permitted.
19.SPRINGS
   a.Either rear coil or leaf springs permitted.
   b.No transverse coil spring mounts permitted.
   c.Coil springs must be a minimum of 4-1/2 inches in diameter.

FUEL / FUEL SYSTEM

1.Track racing fuel is permitted.  If fuel other than track fuel is used, it can match, but must not exceed testing results of track fuel.
2.No fuel additives permitted.
3.Only OEM type mechanical fuel pumps mounted in stock location permitted.  No electric fuel pumps permitted.
4.Fuel lines must be of armored hose, or installed in metal conduit, or steel fuel line and must not be routed through driver compartment.

FUEL CELL

1.Mandatory with a maximum of 22 gallons including fill spout.  Fuel cells with a plastic or rubber bladder  required.
2.Must be encased in a container of 20 gauge steel or 1/8 inch aluminum.  In addition, must have 3, 1/16 inch steel protection plates on rear and sides of fuel cell that attach to square tubing, straps (see diagram #1), or frame of car.
3.Fuel cell height is measured from ground to any point on bottom of fuel cell.   Minimum of 11 inches permitted.
4.Must be located between frame rails behind rear axle.
5.Must have drag loop extending below bottom of fuel cell.
6.Must have check valve on vent tube or cap.

ROLL CAGE

1.Must be constructed of no less than 1.66 inch diameter by 13 gauge (.095 inch) carbon steel round mechanical tubing.
2.Must be welded to frame of car in no less than 6 places.  Cannot be welded to body.
3.Must have a 3/16 inch inspection hole in 1 main upright.
4.Bends must not have any kinks.
5.Must be kept inside of car.
6.All joints must be completely electric welded all around and be slag free.
7.Minimum requirements for all roll cages are as follows:
   a.4 upright bars and 3 overhead bars.
   b.1 of the following are optional for driver side door bars:
   c. 4 curved horizontal bars connected by vertical tubing (   1-1/2 inches diameter minimum).
   d. 3 curved horizontal bars connected by vertical tubing (   1-3/4 inches diameter minimum) with 1/8 inch steel   plating welded to outside of door bars to cover openings between tubing.
   e. 3 horizontal bars in passenger door connected by vertical tubing.
   f.  1 horizontal bar in dash area connecting front uprights.
   g.  Roof support bar
   h.  Vent window brace on driver side
   i.   Tubing to protect driver's feet (diagram #3).
   j.   Rear hoop brace (diagram #4).
   k.  Complete engine compartment and trunk compartment braces are required.

SAFETY EQUIPMENT

1.Onboard fire-out system recommended.
2.Radio communication permitted.
3.A scanner that is programmed to receive the track frequency will be required.
a.Teams with radio communication with the driver; crew chief or driver may have the scanner.
b.Teams without radio communication with the driver; driver must have the scanner.

MISCELLANEOUS

1.Carbon fiber clutch or drive shaft, ceramic valves, or other new high technology, high expense items will not be permitted in competition.
2.Post-race inspection is mandatory for any car directed to the inspection area by officials or any car competing with a weight penalty that finishes the feature race.