This Page Last Updated:
Dec. 7, 2016
Ultimate/Ultra 275 Street Rules 2017 (updated
1/8th mile Eliminator
Fiberglass/Carbon body panels are limited to hood,
rear deck lid, fenders, doors, and bumpers. Cowl
hoods may not be taller than half way point of the
windshield. Forward facing scoops are prohibited
on power adder combos unless factory installed or
less than 5 inches from flat area of hood. Inlets
for turbochargers and superchargers must not be
exposed to ram air and pass a "line of sight
inspection" from the front of the vehicle, I.E.
they must be blocked off from a source of air this
includes closing off factory holes/grills. Factory
floor must remain under driver and passenger seat
area, fwd of the rear door jamb. All front ends
must be of factory dimensions and cannot be
lengthened and must meet all NHRA/IHRA height.
(See ground clearance note below). Race car
lettering limited to windows, side of cowl hoods,
side of hood scoops, side of rear wings and front
chin spoilers, to maintain street type appearance.
Minimum 3 inches from front of car to 12 inches
behind centerline of front axle, 2 inches for
remainder of car, except oil pan, oil retention
device, and headers.
Aftermarket steering columns are allowed. Factory
type dash accepted. Must have carpet.
Optical devices and magneto ignitions are
prohibited. All entries must have operational head
lights and tail lights.
Aftermarket stock bore space blocks and cylinder
heads are allowed. All entries must utilize a
single carburetor cast intake manifold (see
induction section below). Motor plates and solid
mounts are allowed. Engine must be in stock
location. Mufflers are required on all vehicles
(except turbocharged combos). All SB power adder
engines are limited to 440 cubic inches. SB N/A up
to 480 cubic inch permitted with added 7 lbs. per
cubic inch over 470 and BB N/A limited to 632 and
BOP/BB Mopar power adder limited to 540. Any
engine in question will be measured with a P&G
gauge. A correction factor of 1.5% will be used.
Competitors may be asked to remove a cylinder head
for bore and stroke measurements should any
Small blocks, Mopar -BOP, and BB N/A combinations
may use a "Commercially available/mass produced
4150 or 4500 series cast intake only" No 8500
series throttle bodies or stretched dominators -
The Cast Holley LS EFI ram intake is permitted on
boosted combos. Small Block N/A may use cast
tunnel ram/sheetmetal/dual carbs w/weight penalty
(See*below) Mod motor permitted aftermarket ram or
Nitrous limited to SB and BOP/Mopar BB entries -
Progressive nitrous controllers are allowed.
Entries must utilize a single stage nitrous plate
with one nitrous, one fuel and one redundant purge
solenoid. Cross bar plate on BB Mopar (BOP
permitted #6 from bottle to solenoid) entry
limited to #4 single line from #4 bottle nut to #4
fitting @ solenoid. BB Mopar/BOP entry permitted
single stage, single bar plate with #6 single line
from bottle to solenoid. 8.2 deck SBF combos
permitted single stage fogger. Single 10 or 15lb
bottle on with a maximum #6 line size from bottle
to solenoid. Foggers must be disconnected and all
solenoids must be capped off. Cold Nitrous
prohibited. Push systems prohibited. Nitrous
plates using fogger nozzles prohibited. Purge line
must clearly exit the hood/cowl or body in a
fashion to not allow purged nitrous to enter the
engine when racing.
Turbocharged (mid frame turbo only see list below)
and supercharged (must be unmodified from
manufacturer) entries are limited to stock valve
angle SB combos only. (SB CHEVY 23 DEGREE - SB
FORD 20 DEGREE 18 DEGREE MOPAR - FACTORY HEADED
SMALL BLOCK FORD MOD MOTOR - LS CHEVY 15 DEGREE -
GEN III Hemi SBM - TFS-R Head - Stock Z06 LS 12
degree Casting for Corvette)
** NOTE: SB Chevy 23 degree RR - SB Ford 20 degree
- (SR20 FT1 or T1RI or equivalent with boosted
combo +50 lbs)
Pump gas, E85, M1, Q16, and C12/16/23/45 NO2 or
equivalent racing fuel. M5 Prohibited
Any OEM style automatic or OEM manual transmission
is allowed with power adder. Clutch
assisted/clutch-less manual transmission allowed
on N/A. Manual transmissions must utilize SFI
approved bell housing.
Stock type rear suspension or ladder bar only.
Coil over shocks are allowed. Anti-roll allowed.
Aftermarket replacement control arms are allowed.
Stock frame rails must be in factory location,
notching permitted. Corvette permitted any type of
transverse leaf spring rear suspension. Wheelie
bars are prohibited on all cars. Late model GTO
permitted torque arm or ladder bar w/ additional
weight (see below)
Factory type front suspension only. Coil over
shocks are allowed. Aftermarket replacement
control arms are allowed. Aftermarket
K-Members/Commercially available sub-Frames
allowed. (Must have prior approval from tech)
Strut towers must be in factory location with
factory sheet metal attaching factory frame rail
to top of strut tower.
POWER ADDER LEGAL TIRES: 3553 255/60-15 ET Street
3453 275/60-15 ET Street S/S
3052 26 x 8.5-15 ET Drag
3052R 26 x 8.5R-15 ET
N/A LEGAL TIRES: 3754X 275/60-15 Radial Pro 3055S
28 x 10.5-Stiff Wall Bias Ply Slick 3055 28 x 10.5
Standard Bias Ply and any of the listed POWER
ADDER LEGAL TIRES
Inline non-stock valve angle head 3075 chg.
Mopar BB conventional B1 head/BOP combo 3075
Any canted valve head 3100
Any non-raised runner 23 degree combo 2950
Any raised runner 23 degree combo - 3050
Blue Thunder Cylinder Heads 4.3 /SC1 - 3200 and
3.6 - 3075
C3/C302B/C302/Yates style -3000
Any 20 degree ford 3000
Any 20 degree high port SR20 FT1 or T1RI or
equivalent - 3050
TFS-R Ford - 2950
F1A - 91 series - 3050 (-94 series add 150 lbs.)
F1C- 91 series 3100
YSI 3000 (deduct 50 for cast wheel) chg.
4.0L - NHRA SS COPO - 3300 (must have run NHRA SS
to be legal)
T-76 3000 chg.
N/A WEIGHTS: TBD
N/A Inline head up to 440 2550 chg.
N/A Non-Inline head 2650 chg.
N/A Buick/Olds/Pontiac 2850 chg.
N/A (big block with 9.8 standard deck height and
conventional head) 2850 lbs. (add 2.5 lbs. per cu
in over 589) chg.
N/A (big block Ford with standard deck height and
conventional head) 2850 lbs. over 589 add 100 lbs.
N/A (big block with tall deck height and
conventional head) 2900 lbs. over 589 add 100 lbs.
N/A (big block with 9.8 standard height and big
chief head) 2950 lbs. (add 2.5 lbs. per cu in over
N/A (big block with tall deck height and big chief
head) 2975 lbs. over 589 add 100 lbs. chg.
N/A (big block Ford with standard deck height and
non-conventional head) 2975 lbs. over 589 add 100
N/A (big block GM with Symmetrical
port/non-conventional head) 3000 lbs. over 589 add
100 lbs. chg.
N/A (big block Ford with Pro Stock/Symmetrical
type cylinder heads) 3050 lbs. over 589 add 100
- No Billet cylinder heads/blocks
- No Billet wheels on any turbo combo
- No Reducers on turbo or supercharged combo
- Alcohol/E85 legal (meth injection legal on non-intercooled
- All turbochargers (mid frame GT47 or S400
chassis only) must be as manufactured from factory
with cast wheel(GT47-76/S400)
- Cast compressor inducer cannot exceed 76.6mm and
the compressor exducer cannot exceed 116 mm
- 76.5 mm compressor wheels must be "as-cast"
- Turbine wheel must not exceed 96.2 mm x 88.3 mm
- All turbochargers and blowers will have the
compressor cover removed for tech inspection
- No muffler required on turbo entry, required on
all other combos
- No bull horns - front exit exhaust permitted but
must not effect timing equipment
- Gear driven supercharger allowed
- Belt driven supercharger deduct 50 lbs.
- Boosted GEN III Hemi SBM add 50 lbs.
- Non Intercooled boosted combos deduct 50 lbs. on
gas (add 50 lbs. boosted combo on M1) chg.
- Late model GTO permitted ladder bar or torque
arm add 50 lbs.
- Cast Tunnel Ram/Sheetmetal/Dual Carbs on SB N/A
add 50 lbs. - Single 4150 carb/throttle body used
with 4150 intake manifold and 4150 plate system
deduct 50lbs (N/A or NOS only)
- N/A may deduct 100 lbs. if using M/T 3754R or
3453 tire (except Pro Stock type cylinder head)
- N/A BBC and BBF deduct 25 lbs. for NO forward
- V6 - I4 - I6 entries deduct 200 lbs.
- 8.2 deck nitrous combo deduct 150 lbs.
- Single entry 1 nos/1 fuel or single nos (dry
system) plate deduct 50 lbs.
- 4 NOS Jet dry plates add 50 lbs.
- 2 NOS Jet dry plate not eligible for single
entry plate deduction
- COPO permitted aluminum block
- IRS deduct 50 lbs.
- any SMALL BLOCK COMBO 441 to 465 ci add 2 lbs.
per cubic inch over 440. Blown/BOOSTED combos NOT
permitted over 440 ci
Accepted products deadline for Ultra Street/X275
Motorsports; Requests from manufacturers to have
new products considered for addition to the 2016
season should be submitted before December 10,
2015 for the 2016 season. After this date, Ultra
Street/X275 Motorsports will not consider
manufacturer requests for new products for the
2016 season. Tech director reserves the right to
adjust rules at any time for parity.
ALSO: EVENT / RACE INFORMATION