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2017 Performance Engine Guide
Engines and Components >>
Modified Engine Guide >>
2017 Head and Carb Packages

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• Signature Series Pro Clone Engine Package $1,150
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• Free Powder Coat with any new JRPW Engine Package

2017 Performance Engine Guide

Signature Series Pro Clone Engine NKA / AKRA….$1150
Based upon our highly successful 2016 package, this one is all that and more. Every 2017 JRPW Clone engine package includes a machined and/or ported cylinder head. Be assured, research, development, and rules updates over the last couple years have created huge gains in power and RPM range here at JRPW. We have the research and development program as well as the machinery, tooling, and test equipment to keep you ahead of the pack. All JRPW Box Stock engines are fully blueprinted to the edge of the rules limitations, painstakingly reassembled, and dyno tuned to the highest of standards. We walk all over the line, but stop short of stepping across. Diamond cutting, honing, polishing, degreeing, flowed, tested, measured, cc’ed, are just a few of the procedures performed on each engine we build. Every engine package is complete with sleeved header and muffler assembly, all linkages, and chain guard. We only offer one package, “The Best!” Custom Powder Coating in the color of your choice is also included.

Signature Series Animal Engine…..$1550 
This is the King of the Hill. Briggs & Stratton’s overhead valve racing engine, all grown up and ready to race. We begin with all the machine work allowed by the rules, and then we rev it way up. We diamond machine the valve seats, throw in a pair of our blueprinted valves and add a ground camshaft to get us started, but the objective is clear, Horsepower. The carb is reworked and prepared to give maximum flow and properly tuned for your application. There is quite a bit of work done that although you may not see it, it is the difference between racing and winning. This engine comes with the throttle kit, all necessary linkages, as well as header and muffler assembly. We have been building and racing these engines since their inception and and could not be more pleased with the results, and we have an aggressive Research & Development effort that never rests. Not only are we ahead of the curve, it has faded from our rear view mirror. As with all our engines, it is dyno tuned, tested and ready to race. Pick your color, your division, and get ready for victory lane!

Signature Series Dual Bearing Flathead….. $1675
Our quality machine work, testing, and experience set this engine apart from the competition. This engine is fully machined, with replacement valve seats and full length valve guides precision honed to size. We weld the lifter bore, angle deck the cylinder, and port and polish for max airflow. We align bore the cylinder and finish hone to exacting clearance. The valve seats are perfectly finished with our diamond cutting process. We add a pair of blueprinted valves, a pair of perfectly matched valve springs, and top off the cylinder with one of our machined heads. We complete the package by adding one of our signature “Attack Series Carbs”, with its precision machined body, offset throttle shaft, and hand picked internal parts to insure the highest possible airflow. Included in this are a pair of billet lifters, billet rod, and all the go fast goodies we can legally fit inside this powerhouse.  Each piece is hand selected to insure maximum horsepower. This engine comes standard with our billet header support, oil vent kit, and a lightweight filter adapter. Restricted class engines also include a max-size restrictor plate. Dyno tested and tuned to meet our highest standards of quality, this engine is ready to bolt on and win,,,,,,, just add oil and fuel. Powder coating is also included at no additional charge.

Signature Series Pro OHV Open Modified.....$2450 
Beginning with the clone engine, we completely gut the case and precision overbore the cylinder WAY oversize. The case is machined to accept all the high performance internals we use. We also take the time to brace the block for additional support. The head is fully modified with 32mm and 28mm stainless valves and topped with dual valve springs and hp retainers. Compression ratio is calculated and parts are machined to optimize performance. Roller shaft rockers finish the head assembly. Billet crankshaft, billet rod, forged piston, billet crankcase cover, and a billet flywheel are all standard equipment. The package is completed with a blueprinted Mikuni carb, as well as the header/ muffler assembly. This one is definitely not for the faint at heart, as this engine makes in excess of 31 hp. Practice your grip, you will need it to keep this monster under control. An upgrade to a Honda block is an additional $100

Modifieds, Drag Engines, Outlaws........  
For those who want to get there in a hurry, we can fulfill your every need. Mild to wild and everything in between. Power, Power, Power, this is the way to go. We start with the same quality machining as in our other engines, then we get carried away and add all the “tricks” and other go fast goodies and machine work that makes these engines scream. We top off these packages with a fully prepped carb based on your application. Better hold on tight, it’s gonna be fast. Contact us for quotes.

Rebuild Services……
Rebuilds begin at $225 plus parts. Some engines may require additional machine work at an additional charge. Quotes are available.

Each engine comes with a spec sheet that will provide the owner with specific information for their engine. It also provides care and maintenance information to keep your engine at its peak performance between rebuilds. 

Prices do not include shipping and are subject to change. JRPW makes every effort to maintain pricing; however with the rising costs and parts updates, adjustments may be necessary.


2017 Engine and Component Kits

JRPW Pro Clone Kit......$795  
For the racer that wants the JRPW touch, with the option to assemble the engine on their own, this is the kit for you. This kit will provide the racer access to the precision machine work and parts selection that has made JRPW one of the premier shops in karting. Complete with our trademark “Attack Series” cylinder heads and carbs, header, muffler, etc, these kits include every bolt, bracket, clamp, and gasket necessary to make the engine track ready. Fully machined and ready for assembly. Just as with all JRPW engines, a custom powder coated engine cover in your choice of color is standard. Instructions and specs are included.

JRPW Pro Upgrade Kit.....$219
Created for the racer with an existing engine lacking that extra bit of needed HP. This kit includes our “Attack Series” head and carb, camshaft, timing key, and all needed gaskets to reassemble. Cam and timing key selection is based on your particular division. Like always, instructions and guidance are included without additional charge. Upgrade to a 2017 head assembly for an additional  $50

JRPW Clone Kit Stage 1......$339   
This is a you build it kit that has all the parts and pieces to get you track ready. Includes the Box Engine, BSP-3 cam, HD valve springs, top plate and linkage kit, special spark plug, filter adapter, fuel pump, chain guard, as well as billet flywheel and appropriate key. Carb jets are drilled and pulse fitting is installed.
Popular Options and add- ons:
Dyno Cam..................................+$15
Small Pipe/ Muffler assembly...+$45
Big Pipe/ Muffler assembly.......+$89

JRPW Mod Kit Stage 3.....$435 
For the racer or enthusiast looking to build a modified engine without breaking the bank, here we go. Components of this kit include; Clone crate engine, Top plate and linkage kit, fuel pump and hose, billet high flow filter adapter and filter, Mod 2 Dyno cam and matching valve springs, billet flywheel and timing key, billet rod, drilled carb jets, and all needed gaskets. The head is cut to increase compression, and pulse fitting is installed into the valve cover.
Popular Upgrades and Add-ons;
JRPW .650 Carb.....................+$75
JRPW .690 Carb.....................+$89
Header/ Muffler/ Brace Assy..+$89

Predator Mod Kit Stage 3......$359
Same items as above, but specific to the Predator engine. Engine is not included in this package. Specify engine style, Hemi or Non-Hemi

JRPW SSX Head Kit....$119  
Clone or Hemi Predator. This kit has all the needed parts to bulletproof the top end of your clone  engine. Stainless steel valves, 24mm and 25mm,  HD retainers and locks, dual valve springs, and a Champion rocker arm assembly, make up this kit. This is an absolute must for engines operating above 7500 rpms.  This kit is also compatible with the original style Predator engines.    

Clone Stroker Kit.....$459.95 
Includes ARC billet crank, ARC billet rod, Wiseco piston assembly, and HD wrist pin. Available in bore sizes from 2.682 to 2.815

Animal Stroker Kit....$509.95 
This includes an ARC billet crank, ARC billet rod, Wiseco piston, HD wrist pin, correct timing gear, pto bearing, and pto oil seal. Bore sizes from 2.702 and up. 2.756 is often the largest bore the stock sleeve will accommodate.

JRPW 3” Clone Blocks......$229.95 
High grade cylinder sleeve installed,  finish bored and precision honed to size. To prepare using a Honda block, add $100
Welding and braced, add $85

JRPW Modified Clone Blocks…..
Big Bore, Welded and Braced Clone Block $205
Honda Block $299


2017 Modified Engine Guide

Signature Series Pro OHV Open Modified.....$2450 
Beginning with the clone engine, we completely gut the case and precision overbore the cylinder WAY oversize. The case is machined to accept all the high performance internals we use. Time is spent bracing the block for additional support. The head is fully modified with 32mm and 28mm stainless valves and topped with dual valve springs and hp retainers. Roller shaft rockers finish the head assembly. Billet crankshaft, billet rod, forged piston, billet crankcase sidecover, and a billet flywheel are all standard equipment. The package is completed with a blueprinted Mikuni carb, as well as the header/ muffler assembly. This one is definitely not for the faint at heart, as this engine makes in excess of 31 hp. Practice your grip, you will need it to keep this monster under control. An upgrade to a Honda block is an additional $100

Signature Series Stock Appearing.....$2099 
This engine uses the same internals and machine work as our Signature Series Open Modified, just in a stock appearing format. The best of the best, its all there. Topped off with one of our killer 690 Attack Series Carbs, or, if allowed, a prepared and bored 390 carb. As with all JRPW packages, it comes complete, powder coated, and ready to race, including all bolt ons and accessories. 

JRPW Level 5 Modified.....$1675 
For the Modified racer wanting a lot of HP at a lower cost, this is a package that makes the power and is upgradable to make even more power. Included is a big bore, long rod rotating assembly with a stock stroke. We top it off with a ported and machined cylinder head assembly including stainless valves, HD retainers, dual springs, and an aftermarket rocker assembly. We feed the air to this package with one of our 690 Attack Series Alky Carbs, with a Mikuni upgrade for an additional $149.95. This is a race ready package, pick a color, and bolt it on.

JRPW Mini Mod.....$1375 
For the budget racer wanting a reliable engine package that packs a big punch, here you go. We upgrade the cam and valve springs, add a billet rod and flat top piston, and assemble it all to our precision standards. The head is machined, and we add one of our 650 Attack Series carbs. Billet flywheel, header assembly, chain guard, its all there and ready to race. Pick your fuel, alky or gas, and pick your color, we will handle the rest.

JRPW Open Clone Cylinder Head Level 10.....$275 
When all out HP is the goal, this is the only choice. Precision machined with 32/27mm machined stainless valves. Valve bowls are machined and hand blended into the runners.  As with all our heads, seats are diamond machined, to insure proper seal. Air, air, and more air, thats what this head is all about. Decked out and ready to bolt on, includes dual springs, HD retainers and locks.

JRPW Open Animal Cylinder Head....$335  
Beginning with the the improved Briggs RT-1 casting, we add the JRPW touch. Stock seats are removed and the pockets are machined to accept 1.25”/ 1.12” machined stainless valves. Ported, blended, and decked to our highest of standards, no stones are left unturned in our quest to provide you with the most possible HP. Includes springs and HD retainers, ready to go.

Clone Stroker Kit.....$459.95 
Includes ARC billet crank, ARC billet rod, Wiseco piston assembly, and HD wrist pin. Available in bore sizes from 2.682 to 2.815

Animal Stroker Kit....$509.95 
This includes an ARC billet crank, ARC billet rod, Wiseco piston, HD wrist pin, correct timing gear, pto bearing, and pto oil seal. Bore sizes from 2.702 and up. 2.756 is often the largest bore the stock sleeve will accommodate.

JRPW 3” Clone Blocks......$229.95 
Precision Cylinder sleeve installation, and finish bored and honed to size. Honda block, add $100


2017 Head and Carb Packages

 JRPW Attack Series 2017 NKA / AKRA Machined Head….$159.95
This is the same cylinder head used on our Signature Series Engines. No doubt about it, these are some of the absolute best prepared heads in the industry. Fully machined and assembled, ready to bolt on and go. NKA heads have valve bowl machined to spec, AKRA heads are ported. Includes stainless valves, hand picked springs, and rocker arms. Valve lift will need to be checked once installed to verify legality and performance.

JRPW Attack Series Stock Head….$109
This head has won races all over the country over the last few years. It has the same valve job and parts as the ’17 model, just with standard valve bowls and it is un-ported. This head is still an excellent choice at a lower price point.

JRPW Attack Series Blueprinted Clone Carb.....$49.95 
Maximum airflow and a matched fuel curve are imperative for any engine to perform at its peak. JRPW machines all carbs to the edge of the technical limitations. Each one is properly jetted and throttle position set. Carbs available for all classes, restricted and unrestricted.

Attack Series Deep Breather Kit 2017 .......$209.95
This kit contains one of our Precision Machined “Attack Series” cylinder heads as well as one of our “Attack Series” Clone carbs. Every piece is maximized for the highest level of performance. Everything you need to improve your performance is included in this package. The standard package is $159.95                                                                     

JRPW Open Clone Cylinder Head Level 10.....$28
When all out HP is the goal, this is the only choice. Precision machined with 32/28 mm machined stainless valves. Valve bowls are machined and hand blended into the runners.  As with all our heads, seats are diamond machined, to insure proper seal. Air, air, and more air, thats what this head is all about. Decked out and ready to bolt on, includes dual springs, HD retainers and locks.

JRPW Open Clone Cylinder Head Level 5.....$24
For the smaller modified engines or the stock appearing engines with smaller carbs, this may be the best choice. An oversize intake valve seat is installed along with a 28.5mm stainless valve. Exhaust is a stock diameter stainless valve. Professionally ported and blended, it comes complete with spring package of your choosing, HD retainers, and guide plate.

JRPW Open Animal Cylinder Head....$335  
Beginning with the the improved Briggs RT-1 casting, we add the JRPW touch. Stock seats are removed and the pockets are machined to accept 1.25”/ 1.12” machined stainless valves. Ported, blended, and decked to our highest of standards, no stones are left unturned in our quest to provide you with the most possible HP. Includes springs and HD retainers, ready to go.

Mikuni Carbs by JRPW......
JRPW has been providing racers all over the country with custom blueprinted Mikuni carbs. Gas or Alky, Mikuni carbs by JRPW offer incredible throttle response and partial throttle power over other carbs. From 24mm up, we can fulfill all your carb needs, Clone, Animal, and Flathead. Kits include carb, filter adapter, custom intake, and all necessary linkages.

Tillotson Carbs by JRPW.....
For the racer that has a preference for the Tillotson carb, JRPW can prepare the carb of your choosing. From small bores to large and everything in between, we have been building some of the country’s best Tillotson carbs for years. Let us know your application and needs, and we can take care of the rest.

“The JRPW 390” Carb Kit…..$215 
JRPW is pleased to introduce our version of the 390 Honda carb. Bored and machined, this will bolt on lots of HP and still resemble a stock style carb. If rules allow, this is an excellent choice. Machined Carb $165 separately.

The 690” Clone Carb........$114.95....
The Ultimate in stock body GX 200 carbs, with a .690 bore. Outside epoxy is used because of the huge internal diameter . Every internal part precision machined to provide the highest possible airflow. Alcohol or Gasoline versions available.

The 650” Clone Carb,,,,,,,$109.95.....
The same precision work as our 690 carbs, but with a smaller bore. Perfect for stock appearing and mild outlaw classes, or any division where the presence of epoxy is disallowed.

Stock Animal & Flathead Carbs by JRPW....
Allow JRPW to build the carb to bring out your engine’s potential. Every carb is precision machined and tweaked for maximum airflow using hand picked internal parts. Flow tested and properly jetted by division, JRPW stock class carbs are consistently in Victory Lane. Restricted or unrestricted, choose JRPW.