400 RACE ENGINE MODS - Back to Engine Mods

HPD-763-389-3336

Reed Spacer
Kit 400

THIS ITEM IS ON SALE!
$25.00!!

For Polaris 400 only. Increases horsepower and extends reed life. A must for big bores, to correct primary compression.

Race Porting

Designed for the 400 Polaris engine. This porting makes this engine the horsepower champ stock cylinder 400 Polaris ATV's. Tremendous power from a wide, hard hitting power band, and it's still dependable. Produces 73 to 75 horsepower at 7450 RPM with the proper additional parts. 70 plus horsepower in under 2 seconds on a warmed up engine.
This baby lights fast!

Requirements: Race modifications

NEW!!

High Output Ignition Upgrade
for 400 / 416

High Output Ignition Upgrade for 400 / 416

Finely tuned, higher output replacement source coil, ignition coil, and CDI Box. Output is 35% higher voltage and higher amperage than original parts. Now you can gap your plug at .025" or more without any misfiring. Because of the wider gap and higher voltage, horsepower output WILL increase.

Spark Plug wire and retainer suggested

Ignition Upgrade
PART # PM4IGU
• LIST $290.00

NOTE: You must recheck your jetting.

WISECO
Forged Pistons

Due to past experience with broken pistons on modified ATVs, we require WISECO pistons be used on all modified engines, and recommend them for all others. Includes: Piston, rings, pin, and clips.

REQUIRES: Cylinder honing or boring.

Custom
Forged Pistons
400 Big Bore

Bore Cylinder

Send us your cylinder, and we will bore, hone and chamfer the ports.

Fill out this form to send with mods

Remove .04" to .08" material
PART # BORE+
• LIST $75.00

Remove up to .04" material
PART # BORE
• LIST $65.00

Big Bore- Remove .1" or more
PART # BOREBB
• LIST $85.00

Race Mod Kit

Run the same kit as the past drag race champions. Save money by purchasing this complete kit!

Flywheel Lightening

400 Race Lightening

Removes electric start and lightens flywheel by 2.3 pound. Make engine rev extremely fast.

Flywheel not included ... send us your flywheel and HPD can dynamically spin balance your flywheel to .5 grams. Prices are for the labor to machine and balance your flywheel to race or trail specs.

PART # LFR
• LIST $115.00

400
Race Mod Pipe

RACE MOD PIPE

Highest horsepower pipe for the race mod Polaris 400 cylinder. Good wide power, pulls from 4500 to 7500 RPM.
Includes manifold, pipe, stinger, exhaust springs.

NOTE: Muffler sold seperately.
Black finish only.

Scrambler/Sport/Trail Blazer
PART # ATVRP8
• LIST $325.00

Click here for Mufflers

Billet Head,
Cover & O-Rings

A must have for the Polaris racers and performance riders.

Our billet, 2 piece head, is a complete design, and not just a machined copy of the original stocker. It provides concentric water flow, thus preventing hot spots. Sealed to the cylinder with O-rings to create a metal to metal contact, providing even engine temperatures. The improved combustion chamber pocket and squish area, increases horsepower and torque. Additionally, the head allows girdling through the cylinder to the crankcase, providing a much stronger and durable package.

Girdle kit is optional. Not for use on 416 PowerMAXX.

Trail Mod 400s
Designed for stock, piped or trail mod 400s on 92 octane fuel. Improved torque and horsepower.

Trail Mod 400s
Designed for stock, piped or trail mod 400s on 92 octane fuel, but for 4500 feet or higher altitude.

Trail or Race Mod 400s
Designed for 105 octane race gas on trail or race mod engines. Great horsepower.

Race Mod 400s
Designed for use with 110 plus motor octane fuels on race mod engines. Best horsepower.

Billet Head Girdle Kit

For Polaris 400 cyl. only (not for use on 416 POWER MAXX products).

For Polaris 400 cyl. only (not for use on 416 POWER MAXX products). Send in Cylinder to HPD for modification.

Replacement Chambers for Billet Heads

Often copied but never duplicated.

ChamberType: High Alt.Pump Gas 400
Gas Type: 92 Octane/Pump

ChamberType: Race Gas
Gas Type: 110 Octane/Race

These kits are industry leaders for providing smooth and precise upshift and backshift, which improves your efficiency, performance and durability. Tunable with custom cam angles and springs. Twin roller operating in enclosed helix track.

MUST STATE MODEL OF MACHINE IN "COMMENTS" SECTION OF ORDER FORM.

PART #TAS-03X
• LIST 369.00

Secondary Clutch Assembly ONLY

Same secondary clutch as above,
but just a secondary clutch assembly

PART #TAZ03X
• LIST 339.95

Team Secondary Clutch Springs

Secondary springs control shift rate.
Fine-tune your secondary clutch with TEAM springs manufactured to the most exacting specifications.
Spring Height at 2.4" - 1.4"

Black/Red
120-185 Wt
PART # 210090
• LIST $24.95

TAS03X Team Secondary
Clutch Springs
Chart 1
Load Heights at 2.05" + 1.05"

Secondary springs control shift rate.
Fine-tune your secondary clutch with TEAM springs manufactured to the most exacting specifications.

Bright Green/Purple
105-185 Wt
PART #210314-001
• LIST $24.95

TAS03X Team Secondary
Clutch Springs
Chart 2
Load Height at 2.0" - 1.0"


Secondary springs control shift rate.
Fine-tune your secondary clutch with TEAM springs manufactured to the most exacting specifications.

Green / White
105-185 Wt
PART # 210215
• LIST $24.95

Team Helix's

EBS and NON-EBS
Helix's

Aggressive Clutch Kits

Kit includes: Helix, weights, 2 springs, installation guide, and shims (if needed).

Aggressive clutch kits are faster accelerating, plus more mid range response. Back shift is improved at all speeds. These kits also improve belt life. All have been tested for accuracy on dynoed engines with on board computers. This is the best performing trail set up.

400 Sport/Scrambler
(Race)
Designed to be used with race ported motor and ATVRP8 pipe.

PART # CK4RM8
• LIST $190.00

Rear: 30 Teeth
PART # 351355-001
• LIST $30.00

Rear: 34 Teeth
PART # 3222068
• LIST $45.42

Rear: 36 Teeth
PART # 3222109
• LIST $62.45

Single Throttle Cable for Polaris -
Metal Throttle
Part # STC

Single Throttle Cable for Polaris -
Plastic Throttle
Part # STCP

Single Throttle Cable
(for metal throttle)
PART # STC
• LIST $35.00

Single Throttle Cable
(for plastic throttle)
PART # STCP
• LIST $35.00

NEW!!

High Output Ignition Upgrade
for 400 / 416

High Output Ignition Upgrade for 400 / 416

Finely tuned, higher output replacement source coil, ignition coil, and CDI Box. Output is 35% higher voltage and higher amperage than original parts. Now you can gap your plug at .025" or more without any misfiring. Because of the wider gap and higher voltage, horsepower output WILL increase.

Ignition Upgrade
PART # PM4IGU
• LIST $290.00

NOTE: You must recheck your jetting.
Spark Plug wire and retainer recommended.

NEW!!

Spark Plug Wire and Retainer

Use this plug wire with our high output ignition upgrade. Better insulated, high temp cable and cap. Snap on retainer keeps plug wire from coming off plug.

Spark Plug Wire & Retainer

PART # SPW
• LIST $19.00

Fuel Pump Kit

Power Maxx 416s with 47mm carb and some race mod 400s with 39 PWKs require a fuel pump to supply sufficient fuel flow.
Kit includes high output Mikuni pump. Pulse and fuel line, fittings, filter and installation guide.
You will have to change your needle and seat to use this fuel pump

400 Head Gasket

PART # 3084731
• LIST $29.47

Steering Post Bearing

If your steering is loose, this is the product for you. This lower steering post bearing is made of 6061T6 aluminum, has a 660 high impact cast bronze bearing with grease grooves, and is held in place with 1/4 inch allen bolts with nylock nuts. Fits all models with 7/8" steering post.

PART # SPB
• LIST $35.00

Super Duty Clutch Buttons

This kit makes your secondary buttons almost indestructible. Used on our super sport racers for 10 years without breakage.

PART # SSBK
• LIST $65.00

PART # SSB
• LIST $3.00 each

Starter Eliminator Kits

Kits includes: Cover plate, gasket, and 3 nylock nuts.

400 Oil Injection Eliminator
PART # OIEK
• LIST $27.00

Performance
Reed Valves

HPD 416 & 400
V-FORCE Delta II

The dyno proves gains throughout the power band. Improved throttle response and acceleration. These performance reed valves use exclusive custom reed material and stops.

Reed Spacer
Kit 400

For Polaris 400 only. Increases horsepower and extends reed life. A must for big bores, to correct primary compression.

Adjustable
Steering Damper

Hydraulic steering damper for Polaris ATV's helps save your arms and thumbs on rough trails or tracks. The damper unit has a 7-position clicker adjustment. Fits all concentric drive models and Sportsman 500s. Available for 7/8" and 1" steering posts.

For 7/8" steering post

Part # ASD
•LIST $139.00

ATVCT

Disc brake on transmission.
Mounts to frame.

Non-Concentric Chain tensioner.
PART # ATVCT
• LIST $75.00

ATVCTC

Disc brake on rear axle.
Mounts to swingarm.

Concentric Chain tensioner.
PART # ATVCTC
• LIST $75.00

Twin Air Dual Stage Air Filters

Constructed from two layers of high flow, open pore foam, bonded together to provide maximum filteration and superior air flow. Gives you increased power, ease of maintenance, and cost savings.

Round Element for 2001-02 Trail Blazer, also fits HPD 250/400 Aluminum Air Box.
Also used in Predator Clamp-On kit.

PART # TA150900
• LIST $29.00

Heavy Duty
Engine Mounts
80 Durometer
For Performance or Race Engines

Heavy Duty mounts should be used on performance machines to keep the engine in correct alignment, making the clutches more efficient and a faster ATV.

Mounts are sold each (not in sets)

NOTE: Mounts are sold each (not in sets). 250s and 400s require 3 mounts. (Not for use on 500s.)

Clutch Pullers

PRIMARY CLUTCH PULLER:
This tool is used to remove the motor clutch from your Polaris ATV.

PART # 20-66
• LIST $30.00

2-pc Clutch Puller

2-Pc PRIMARY CLUTCH PULLER
This 2 pc tool, specially designed for RZR Ranger, is used to remove the motor clutch . Will work with all Polaris RZR, Ranger & ATV's primary clutches.

PART # RZRPCP
• LIST $35.00

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HPD-763-389-3336