PRO-RACE Holden 202 DCOE tapered bore kit 45, 48, 50mm

BOOSTED VS NATURALLY ASPIRATED:

We have lip seals behind the throttle shaft bearings to stop grease from being sucked out of the bearings under high intake runner vacuum. These are turned around on boosted applications so there is no boost leakage and also stops the bearing grease getting evacuated from the throttle shaft the bearings. 

We ask you if you are going to run your engine Boosted, or Naturally Aspirated so we can install the Lip Seals in your throttle bodies in the appropriate way to suit your application.

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6 Cylinder Pro-Race Kit with Weber DCOE Manifold Throttle Body Kit Contains:

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• 3 x Pro-Race Tapered Throttle Bodies - Butterfly Sizes 45, 48 or 50mm
• 1 x Pro-Race fuel rail kit
• Pro-series 6 Cylinder Linkage Kit (Black) - Includes:
  • High Quality Rod Ends
  • Drop Link - 6061-T6 Aluminium
  • Throttle Stop With Lever Arm - 6061-T6 Aluminium
  • Cable Pull - 6061-T6 Aluminium
• Throttle cable bracket & 6 x Race-Series ram tubes (Black)
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• (TPS, Fuel Rail Fittings and injectors not included) P.O.A. for these items

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LINKAGE AND RAM TUBE COLOURS:

Due to overwhelming demand from our customers, we are transitioning our standard colour from Blue to Black.  Black is a classic colour, and goes with pretty much every engine bay colour and style.

This includes Ram Tubes, Linkages, Cable Pulleys, Drop Links, Bell Cranks, and more.

Don't worry if you love blue, you can still get your kit in blue.  There will be a small premium of $40 per kit to cover us sending out your kit of parts to be anodized blue.  If you would like blue anodizing, please let us know by typing in the notes area of your order.

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QUALITY ASSURANCE:

Every single throttle bore and throttle plate are measured and matched as a pair to ensure the most perfect throttle fit and consistency across every EFI Hardware throttle body.

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THROTTLE BODY TECHNICAL DRAWING

TAPERED BORE THROTTLES

Tapered Bore Throttles have a clear advantage over Parallel Bore Throttles at increasing power and torque. By accelerating the air through a venturi (in this case a tapered bore) the air speed through the throttle body is increased.  This enhances the engine cycle's scavenging effect to provide more air and fuel in the combustion chamber and therefore more power and torque.

The Tapered Bore has 3 sections:

Inlet from ram tube - 48, 50 or 52mm

This then tapers down to a short parallel section for the throttle plate - 45, 48 or 50mm

There is a second taper down to the outlet flange of the throttle body - 43, 45 or 48mm

HP RATINGS

HP/kW Ratings vary from engine to engine.  The power ratings given here are only a guide, and are not absolute power ratings.  Engine power is determined by intake, exhaust, cylinder head design, camshaft design, compression ratio, fuel type and quality and many other factors.

45mm - 54HP/40KW* per throttle - with the tapered bore giving a potential for 5% above this figure.

48mm - 64HP/48KW* per throttle - with the tapered bore giving a potential for 5% above this figure.

50mm - 72HP/54KW* per throttle - with the tapered bore giving a potential for 5% above this figure.

*This number is a guide only and should be used in conjunction with real-world experience.

HIGH PERFORMANCE FUEL SYSTEM PLUMBING TECHNICAL DIAGRAM

Setting up your fuel system right the first time is easy if you follow the right instructions.

EFI HARDWARE PRODUCE 6° THROTTLE PLATES

In the past, 12° throttle plates were the industry standard.  The problem with 12° throttle plates, is that as the plates are moved off the closed position, the change in airflow is huge.  It makes it very difficult to drive smoothly at lower throttle openings.

At EFI Hardware, we only use 6° throttle plates.  This improves off idle and cruise driveability making your vehicle far more enjoyable to drive.

PROFESSIONAL GRADE MANUFACTURE

Manufactured from 601 Cast aluminum and heat treated before being CNC machined.

The butterflies are measured for each bore & precision machined to a 0.0005"" tolerance.

Butterflies are secured to centreless ground brass shafts with split screws to ensure reliability and serviceability.

All are fitted with bearings rather than bushes to eliminate axial shaft movement.

Low stiction bearings for sharp throttle response.

GETTING THE RIGHT BALANCE

The best idle and cruise quality will only occur when every throttle has exactly the same airflow.

The only way to achieve this is to adjust the linkages and/or idle bypass screws and use a tool to measure the airflow at each throttle.

Getting the right balance is not a should, it is a MUST.

We now recommend

and use SKF bearings.