System 01 · with JSR Aerobarrel Technology

Rennen ITB Small Bore

Name: Rennen ITB Small Bore - with JSR Aerobarrel Technology
Brand: Rennen ITB

For 2.7–3.0 litre air-cooled engines with 2-stud heads. Roller-barrel induction with intake bore options of 39 mm or 41 mm - a clean EFI conversion path for early 911, 3.0 SC and similar builds.

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Single Rennen roller-barrel throttle body with velocity stack, CNC-machined EN-AW 6082-T6 aluminium, hard-anodised

Through the bore of a Rennen throttle body: elliptical roller barrel, no shaft or plate in the airflow

Typical applications

Where this system fits

911 2.7

Early small-displacement engines moving from carburettors or CIS to modern EFI - proven on the dyno with a complete build.

911 3.0 / SC

A clean EFI conversion for 3.0 engines with 2-stud heads, retaining the air-cooled character.

Hot-rod 2.7–3.0

Higher-compression builds with sports cams - see the customer cases for documented results.

For 2-stud heads. Final bore (39 or 41 mm) is confirmed against your build at quotation; custom sizes are available on request.

Specification

Technical specification

Configuration	Six individual throttle bodies, one per cylinder
Throttle element	Elliptical roller barrel - no butterfly valve obstructing the airflow; bore fully clear at full throttle
Application	2.7–3.0 litre engines with 2-stud heads
Intake bore	39 mm or 41 mm diameter - or contact us for your custom choice
Bore geometry	Continuous taper from air horn to cylinder head
Material & finish	CNC-machined EN-AW 6082-T6 aluminium, hard-anodised gunmetal grey
Hardware	Throttle barrels in sealed ball bearings; quality bearings and rod ends with stainless fasteners; all sealing by Viton O-rings to prevent false air
Included	Complete throttle linkage incl. rod ends, and fuel rails with bracket for short or long injectors - ready to fit, no modifications needed
Injectors	Made for the EV6 injector type; other injector types can be made to order
Air conditioning	A/C compressor option available with flat right-hand-side throttle body
Custom bores	Custom bore sizes available on request
Engine management	Standalone ECU calibration required. We recommend MoTeC and can provide a MoTeC base map.

Optional add-ons

Stacks/trumpets - 45 mm bore, 120 mm length - $670

Add-on pricing shown in AUD via Rennen Plus; regional pricing confirmed at quotation.

Recommended supporting components

Configure the complete package

Each Rennen ITB system can be configured with injector, MoTeC ECU and ITG filtration options according to engine size, camshaft, use case and installation requirements.

Fuel

Injector package

Specified to your engine and ECU - size, spray pattern and fuel pressure matched to displacement, cams and intended use.

Engine management

MoTeC ECU integration

Recommended for high-control builds. MoTeC base map available as a calibrated starting point; other standalone ECUs supported.

Filtration

ITG filter package

Road, tarmac or gravel specification - protection for the induction system without compromising the ITB airflow character.

Calibration is part of the system.

An ITB conversion only performs as well as its mapping. Plan for professional installation and dyno calibration - see Installation & Tuning.

For coil-on-plug ignition, note that crank trigger wheels are engine-specific - the 964 uses its own, and pulley diameters vary by model, so we machine a wheel to your diameter and TIG-weld it to the pulley. On the 964 the cam sensor lives in the distributor, so a new cam sensor must be installed for coil-on-plug.

Mechanism

Actuation, linkage & trigger hardware

Every Rennen ITB system is supplied complete with its actuation and throttle linkage - machined from billet, running on quality bearings and rod ends for precise, repeatable throttle response across all six bodies - plus the vacuum log, tube set and a crank trigger wheel machined to suit your engine for standalone engine management.

Rennen ITB billet throttle actuator and mounting bracket on a single roller-barrel throttle body — Throttle actuator · billet bracket & rod-end

Rennen ITB throttle linkage with return spring, rod ends and billet arm supplied with every system — Throttle linkage · return spring & rod-ends

Crank trigger wheel TIG-welded to the pulley, installed on an air-cooled Porsche flat-six for standalone engine management — Crank trigger wheel · TIG-welded to pulley

JSR billet vacuum log with black tube set and push-fit fittings supplied with the Rennen ITB system — Vacuum log, tube set & fittings

Specify your system

Tell us about your engine.
We’ll quote the right system.

Every quotation is matched to your displacement, cylinder heads and engine management. Custom bore sizes are available on request.

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