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Discussion Starter · #1 ·
I’m new to the forum so take it easy on me. I have done hours of searching and have not found what I’m looking for. I have a k20a2. I know I can easily make more torque by using a k24 bottom end unfortunately rules don’t allow it. I know bolting on I/H/E to help but with the rules I am very limited. I have not found a build that falls within the rules I’m allowed to run. I will post the rules below and hopefully with the vast knowledge on this forum you can point me in the right direction. I don’t have a HP goal I’m trying to reach. I just need usable power and torque on corner exit. Thanks in advance for the help.
BLOCK:
*MUST BE STOCK OEM PRODUCTION. NO AFTERMARKET BLOCKS.
*EFI: BLOCK MUST MATCH DECLAIRED ENGINE MODEL
*NO BLOCK IS TO BE COATED, POLISHED, OR ANY MACHINE WORK EXCEPT WHAT IS LISTED HERE.
*NO MACHINING TO BLOCK FOR AFTERMARKET ROD CLEARANCE.
*BLOCKS CAN NOT BE OFFSET BORED BUT MAY BE SLEEVED WITH ORIGINAL BORE CENTERLINE.
*STOCK OEM TYPE ROD, CAMSHAFT, AND CRANKSHAFT BEARINGS.
*NO MAXIMUM OVERBORE.
*BLOCKS MAY BE DEBORED BUT CAN NOT WEIGH BELOW FACTORY LB/CC.
*AFTERMARKET PULLEYS AND WATERPUMP ALLOWED.
*CRANKCASE EVACUATION SYSTEM TO HEADER ALLOWED.
*AFTERMARKET OIL PAN ALLOWED.

CRANKSHAFTS:
*MUST BE STOCK OEM CAST OR STEEL, NO AFTERMARKET SUCH AS SCAT, LUNATI, ETC. ALLOWED.
*EFI: CRANKSHAFT MUST MATCH DECLAIRED ENGINE MODEL
*STOCK OEM STROKE OF CRANKSHAFT BEING USED MUST BE MAINTAINED WITHIN +/-.010 “
*NO LIGHTENING OR KNIFE EDGING OF THROWS OR COUNTERWEIGHTS.
*MAY POLISH BETWEEN #4 ROD JOURNAL AND #5 MAIN JOURNAL SURFACE AREAS FOR THE PUROSE OF IDENTIFYING. CRACKS MORE EASILY AND ELIMINATING SURFACE STRESS RISERS, NOT TO LIGHTEN.
*ENGINE BALANCING ALLOWED. MUST BE DONE IN STANDARD PRODUCTION MANNER.
*STUD GIRDLE KIT ALLOWED ON MAIN BEARINGS.
*CRANKSHAFTS MAY BE INTERCHANGED AMONG BLOCKS WITHIN THE SAME MAKE WITH NO MACHING NEEDED. DIRECT FIT APPLICATIONS ONLY ON CARBORATED ENGINES ONLY.
*CC MUST BE POSTED ON HOOD AND MUST BE CORRECT FOR YOUR BORE. ENGINES WILL BE P&G TESTED.

CONNECTING RODS:
*ANY STEEL AFTERMARKET OR FACTORY ROD ALLOWED.
ALL EFI CARS; FACTORY LENGTH ROD
*MAY POLISH STOCK OEM RODS
*NO HOLLOW AFTERMARKET RODS
*TOYOTAS AND HONDAS MAY USE H-BEAM RODS IF NO BLOCK MACHING IS NEEDED

PISTONS AND RINGS:
*ANY FLAT TOP PISTON WITH ANY NUMBER OF RING GLANDS ALLOWED.
*MUST HAVE ZERO DECK HEIGHT
*GAS PORTING IN RING GLANDS ONLY.
*ANY STEEL WRISTPIN ALLOWED. NO TITANIUM PINS
*ANY OEM DOME PISTON ENGINE MAY RUN ANY DOME PISTON. THE FLAT PART OF THE DOME PISTON MAY EXTEND
0.010 “ABOVE DECK HEIGHT.
*ANY STYLE RINGS ALLOWED. MINIMUM 2 RINGS PER PISTON

BEARINGS, FASTENERS, AND GASKETS:
*ALL ENGINE BEARINGS MUST BE STOCK OEM TYPE SLEEVE BEARING. NO ROLLER BEARINGS ALLOWED.
*NO TITANIUM FASTENERS ALLOWED. ANY OTHER FASTENER ALLOWED.
*HEAD AND MAIN BEARING STUDS ALLOWED.
*ANY BRAND GASKETS ALLOWED. NO O-RING STYLE SEALING ALLOWED IN PLACE OF HEAD GASKET

CYLINDER HEAD:
*MUST BE STOCK OEM CASTING. NO AFTERMARKET HEADS ALLOWED
*EFI: HEAD MUST MATCH DECLAIRED ENGINE MODEL (HONDA B20 MAY RUN B18 HEAD AND FUEL SYSTEM AT 2300LBS.)
*ANGLE MILLING ALLOWED
*TWO VALVES PER CYLINDER MAXIMUM ON CARBORATED ENGINES
*STAINLESS STEEL OEM CONFIGURATION VALVES AND SWIRL TYPE ALLOWED
*VALVE STEMS MAY NOT BE SMALLER DIAMETER THAN STOCK FOR HEAD BEING USED WITHOUT WEIGHT PENALTY. IF VALVE STEMS ARE SMALLER THAN STOCK DIAMETER THEN COMPETITOR MUST DROP THEIR LEFT SIDE PERCENTAGE FROM 55% TO 53%
*NO TITANIUM VALVES UNLESS FACTORY REPLACEMENT
*VALVES MAY BE BACK CUT 30 DEGREES MAXIMUM
*VALVE STEMS MAY NOT BE CANTED IN HEAD
*NO INTERIOR DE-BURRING, POLISHING, EXTRUDE HONING, OR ACID PORTING ALLOWED.
*PORTS MUST BE STOCK AS CAST FROM OEM
*LIFTER BORE MAY BE MACHINED FOR SOLID ADJUSTERS
*VALVES MUST RETAIN STOCK DIAMETER HEAD
*ANY STEEL OR STAINLESS STEEL RETAINER/KEEPER/ SHIMS ALLOWED. ANY TYPE OF VALVE JOB ALLOWED. VALVE JOB ANGLES OPTIONAL.
*ANY VALVE SPRING COMINATION OR DESIGN
*REINFORCEMENT ON CAM BOSS ALLOWED
*LATE MODEL STOCK STYLE BOWL CUT ALLOWED. 1 ANGLE UNDER THE SEAT, 1 INCH MAXIMUM DEPTH OF CUT BUT DO NOT TOUCH THE VALVE GUIDE. CUT MUST BE INLINE WITH VALVE GUIDE AND MAY NOT BE HAND GROUND.
*NO BLENDING OF BOWL CUT TO PORTS OR ROUNDING EDGES THAT BOWL CUT CREATES.

CAMSHAFTS:
*ANY AFTERMARKET HYDRAULIC OR SOLID CAM ALLOWED. CAM LIFT OPTIONAL WITHOUT ANY PENALTY.
*ADJUSTABLE CAM GEAR ALLOWED
*STOCK OEM STEEL OR DOUBLE ROLLER TIMING CHAIN AND GEARS WITH HEX ADJUSTMENT SLLOWED.
*ANTI PUMP UP HYDRAULIC LIFTERS ALLOWED
*NO LIGHTWEIGHT PUSHROD
*ONLY STOCK OEM ROCKER ARMS AND LIFTERS THAT WAS FACTORY OEM IN THE HEAD BEING USED
*OIL RETURN SCREENS ALLOWED
*LIFTER VALLEY BAFFLES ARE ALLOWED
*LIFTERS MUST BE STOCK SIZE FOR HEAD BEING USED
*ROLLER ROCKER ARMS ALLOWED ON GM ENGINES AND EFI MOTORS WITH FACTORY ROLLER ROCKERS.

INTAKES:
*STOCK OEM FACTORY INTAKES WITH FACTORY PART NUMBER
*FUEL INJECTION INTAKE ALLOWED
*NO HIGH PERFORMANCE AFTERMARKET INTAKE MANIFOLDS
*NO PORTING, POLISHING, COATING, DIPPING, PORT MATCHING, ETC.
*INTAKE MAY ONLY BE MODIFIED TO ACCEPT CARBURETORS. NO OTHER MODIFICATIONS ALLOWED
*CARBURETOR ADAPTER PLATE MUST NOT PROTRUDE DOWN INTO PLENUM
*ALL PARTS MUST BE MASS PRODUCED ITEMS AVAILABLE AS STOCK PRODUCTION OVER THE COUNTER PARTS. NO SPECIAL TESTS OR MARINE TYPE PARTS.
*ONLY NORTH AMERICAN DISTRIBUTED INTAKES ON DOMESTIC. ASIAN ALLOWED ON JAPANESE MAKES ONLY

EFI FUEL SYSTEMS:
*ONLY ENGINES WITHOUT A CARBORATED OPTION MAY USE EFI SYSTEMS
*OEM THROTTLE BODY FOR DECLARED ENGINE MODEL
*NO MACHINING OR ALTERING OF THROTTLE BODY IN ANY WAY
*OEM UNALTERED FUEL RAIL FOR DECLAIRED ENGINE MODEL
*OEM UNALTERED SIZE FUEL INJECTORS FOR DECLAIRED ENGINE MODEL

AIR CLEANER:
EFI: STOCK UNALTERED AIR BOX OR CAN STYLE AIR FILTERS ALLOWED
*EFI: CAN STYLE AIR FILTER NO LARGER THAN 8” ROUND X 8” LONG
*EFI: CAN STYLE AIR FILTER MUST CONNECT TO THROTTLE BODY WITH SEALED DUCT NO LONGER THAN 8 INCHES. MAY NOT DROP BELOW THE CRANK BOLT.

FUEL & FUEL SYSTEM:
*TRACK FUEL OR PUMP GAS ALLOWED. MUST DECLAIR FUEL TYPE PRIOR TO QUALIFYING. NO E85
*NO ADDITIVES
*NO FUEL COOLING DEVICES
*12 GALLON FUEL CELL MAXIMUM
*FUEL CELL MUST BE MOUNTED IN A CAN MADE OF AT LEAST 22 GUAGE STEEL
*FUEL CELL MUST BE MOUNTED IN CENTER OF TRUNK AREA BETWEEN THE FRAME RAILS. NO MORE THAN 2” DEVIATION FROM CENTER OF REAR OF TREADWIDTH.
*FUEL CELL MUST BE PROTECTED WITH A SUFFICIENT AMOUNT OF STRUCTURE, INCLUDING A BAR BELOW AND TO THE REAR OF THE CAN.
*FUEL CELL VENTING HIGH AND TO THE DRIVERS SIDE RECCOMENDED
*MAY RUN HIGH PERFORMANCE MECHANICAL FUEL PUMP OR ELECTRIC. IF ELECTRIC PUMP IS USED, YOU MUST HAVE ROLL OVER VALVE AND SAFETY SWITCH. THIS MUST BE APPROVED BY TECH PERSON.
*FUEL WILL BE CHECKED RANDOMLY
*EFI CARS CAN RUN FACTORY FUEL TANK IN FACTORY LOCATION ONLY.
ELECTRICAL SYSTEMS:
*BATTERY MUST BE SECURELY MOUNTED AND ENCLOSED TO GUARD THE DRIVER FROM SPILLS OR EXPLOSIONS
*BATTERIES MUST BE MOUNTED IN TRUNK OR THROUGH FLOORBOARD BUT NO LOWER THAN FRAME RAILS
*ONLY ONE BATTERY ALLOWED IN CAR
*ONLY 12 VOLT ELECTRICAL SYSTEM ALLOWED
STOCK TYPE COILS ONLY
*EFI: MUST RUN OEM IGNITION AND ELECTRICAL SYSTEM FOR DECLAIRED ENGINE MODEL (WIRE HARENESS, COIL PACKS, ECT.)
*EFI: OEM STYLE ECU FOR DECLAIRED ENGINE MODEL OR STAND UNITS ALLOWED. NO IN RACE ADJUSTABILITY BY DRIVER OF CREW.
*MSD, ACCELL, MALLORY, ETC. INTERNAL PARTS, COILS, OR MODULES ARE ALLOWED, STOCK TYPE ONLY
*NO MAGNETOS
*NO MULTI SPARK DISCHARGE BOXES (MSD) ALLOWED
*POINTS TYPE ALLOWED
*NO FULL AFTERMARKET DISTRIBUTOR ALLOWED
*NO ADJUSTABLE TIMING CONTROLS
*NO TRACTION CONTROL DEVICES
*ALL WIRING IN CAR MUST BE SECURLY INSULATED AND FASTENED
*ANY SPARK PLUG WIRES ALLOWED
*ANY SPARK PLUGS ALLOWED
*NO DUAL POINT DISTRIBUTORS ALLOWED
*MELS DISTRIBUTORS ALLOWED
*MELS OR MSD TYPE REV LIMITERS ALLOWED (MUST BE MOUNTED IN PLAIN VIEW)

EXHAUST SYSTEM:
*ANY STOCK OR AFTERMARKET EXHAUST MANIFOLD OR HEADER ALLOWED
*4 INTO 1 AND TRI-Y STYLE ALLOWED
 

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2002 DC5 Type S
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For starters, getting a top of the line 4-2-1 header will get you the most usable TQ for pulling out of the corners. I would suggest ASP or Hytech. A 2.75"-3.0" exhaust.

Which factory airbox is the best? The DC5 Type R or The Civic Type R FD2..?
 

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96 civic HX K24a
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It looks like DC 2.2 or similar camshafts and a type r airbox along with a nice header/3” exhaust would definitely help things out and stay within regulations. I noticed you can use race fuel , that would make a world of difference.
 

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2002 DC5 Type S
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On the Type R (DC5) air intake box, one can save money and just buy the 05-06 Type S. The airbox feed is Tube A, Air In pn# 17251-PRC-010 @ $18.98. They are the same parts. The feed tube scoop is the same as the PRC Type R.

I am wondering about the FD2 Civic Type R intake air box and it's changes over the DC5R assembly
 

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Discussion Starter · #10 ·
Thanks so much for the feedback…. What about the block? Pistons, rods combinations? Higher compression? Can’t wait to get this thing built to see what kind of numbers it makes after being tuned
 

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Thanks so much for the feedback…. What about the block? Pistons, rods combinations? Higher compression? Can’t wait to get this thing built to see what kind of numbers it makes after being tuned
Since it says you need to have flat top pistons you probably have to keep the original ones I don’t think you can get higher than 11:1 with a flat top.
 

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2002 DC5 Type S
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** ANY STEEL OR STAINLESS STEEL RETAINER/KEEPER/ SHIMS ALLOWED. ANY TYPE OF VALVE JOB ALLOWED. VALVE JOB ANGLES OPTIONAL.**
-- 3 angle valve job

** ANY VALVE SPRING COMBINATION OR DESIGN **
-- Supertech Beehive Valve Spring. These provide weight savings in the valvetrain department
 

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Discussion Starter · #15 ·
@Them Witches I have a narrow build window and knew it would be best to ask all of you what would be best. I wanted to keep the bottom end stock if possible. As far as the head I was thinking a 5 degree valve job to help with corner exit. Lightweight springs and retainers. Stage 2 cams.(Deciding on the right cam is what started all this).s see one type of header. Kpro and a good tune. That’s basically all I had in mind when starting this. I wasn’t sure what brands. Honestly the more I researched the more confused I would get. One thread would say a certain cam is the best. The next thread it would be garbage. Just so much out there. I hope to start a thread and get direct info for my build. So far the feedback has been great! Thank you all
 

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2002 DC5 Type S
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1,180 Posts
@Them Witches I have a narrow build window and knew it would be best to ask all of you what would be best. I wanted to keep the bottom end stock if possible. As far as the head I was thinking a 5 degree valve job to help with corner exit. Lightweight springs and retainers. Stage 2 cams.(Deciding on the right cam is what started all this).s see one type of header. Kpro and a good tune. That’s basically all I had in mind when starting this. I wasn’t sure what brands. Honestly the more I researched the more confused I would get. One thread would say a certain cam is the best. The next thread it would be garbage. Just so much out there. I hope to start a thread and get direct info for my build. So far the feedback has been great! Thank you all
For starters what chassis are you using?

One of the most popular stage 2 cam I have seen giving good results and seems to always get consistent good reviews is Drag Cartel's 2.2. Supertech Beehive Valve Spring seems to be the lightest and very popular choice too. The beehive takes less material to make vs. standard circles that is why it weights less. The 5 degree valve is said to provide close to 50% of the cfm gains relating to headwork, and is a great choice.

In motorsport racing, the header can be the factor that gives you ability to win sprints after the exiting turns. One made for your build specs can have higher turn around times, so if you go that route which I would, jump on that. For Hytech headers you have to contact John via inlinefour.com. To my knowledge, ASP is not making headers at the moment due to supply costs relating to covid. There are dealers that have ASP headers in stock depending on your chassis, they are $1500. That is what a top level header goes for and in comparison to the $800 header I just bought. ASP & Hytech are worth their weight in gold relating to motorsport racing. If you can gain 8-14whp over a standard mass produced header that would be worth it, the fact you are having a 5 angle valve job in the exhaust you will most likely see the whole 14whp gain over other headers. Plus the TQ gains would be seen throughout and down in the 3500rpm range and up.
 

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Discussion Starter · #17 ·
I am running the DC5 chassis. I have attached an example of what the chassis will look like. The only thing that has to be stock is the floor pan and fire wall. The suspension just has to mount in one factory location. The entire body will not be used and replaced with a stock car body. This is a car a friend of mine built for the same class I’m running in
Sky Cloud Automotive tire Road surface Asphalt
Land vehicle Wheel Vehicle Tire Hood
 

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2002 DC5 Type S
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ASP Header in stock $1350 and up:

Wood Tool Automotive exhaust Muffler Auto part



 
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