Rover V8 Carb Mountings - 4x4 CD175 & HIF44 Carbs
All parts listed are suitable for saloon, sports and 4x4 applications unless otherwise stated.
Note: for inlet manifold heater and bypass pipes, thermostats and housings plus temperature sender units, please refer to the Cooling Section.
Fuel System Introduction
Though various other carbs have been used from time to time, by far the most common carburettors to be found supplying fuel to the Rover V8 are Zenith Stromberg CD175s and SU HIFs.
Chosen for their combination of economy, low emissions and simplicity of operation (plus, of course, availability in large quantities), they are an excellent choice. Nevertheless, the SU HIF6 with manual choke, as fitted to SD1 3500 saloons from 1976 to 1981, is probably the most popular, due to the fact that it can be “tuned” to suit other engine upgrades.
EFi (Electronic Fuel Injection)
Electronic fuel injection first appeared on production Rover V8 engines as early as 1977, bound for the emissions-sensitive Australian market. Subsequently, it was fitted to TR8s and Rover SD1s sold in North America. However, these early systems were designed specifically to meet emissions requirements; it was the Rover SD1 Vitesse, introduced in 1982, that boasted the first EFi system designed to increase power output. Vitesses produced 190bhp from a 3.5 litre engine which was otherwise largely similar to the carburettor version, producing 155bhp.
Three years later, in October 1985, the Range Rover V8 followed suit: EFi replaced carbs for Vogue models initially, and for all V8 4 door models from November 1986.
There ar e four basic types of EFi system fitted to the Rover V8. Similar in operation, they use solenoid injectors - one per cylinder - operating directly into the inlet ports. They respond to information from sensors relating to temperature, throttle position and engine speed, but neither has any control over ignition. The differences between the systems are as follows:
The first system - Lucas L-Jetronic (4CU) - uses an airflow meter, inside which is a hinged flap that measures, by deflection, the flow of air into the engine, thus varying the voltage signal to the engine’s electronic control unit (ECU).
The second system, Lucas 14CUX, introduced to coincide with the ‘new’ 3.9 litre engine in 1988 but also fitted to some 3.5 litre engines and subsequently fitted to 4.2, 4.0 and 4.6 litre engines - incorporates a 'hotwire' air metering system, which contains no moving parts. Instead, it employs two sensor wires - one of which is heated - to measure air mass as it passes over the wires and into the engine. A voltage signal is then sent to the ECU proportionate to the voltage required to maintain the temperature of the heated wire as it is cooled by the air flow.
The two later systems, Sagem GEMS (fitted up to '99 & EOBD* compliant) and Bosch Motronic 5.2.1 ('99 onwards & OBD* II compliant) are complete engine management solutions governing both fuelling and ignition timing simultaneously as well as providing robust immobilisation for added security. Similarly to the earlier Lucas 14CUX system air volume is determined by means of a Hotwire Air Flow Meter. The ECM uses this information in conjunction with data received from the abundance of other sensor inputs associated with these systems to determine the optimum fuel trim at any given time. Additional "knock" sensors attached to the cylinder block detect rough running usually attributed to poor fuel grades, the engine management system uses this information and modulates fuel trim accordingly providing exceptionally smooth running. The result is a far more efficient engine management system with gains in fuel economy and emission control.
The early system, which was fitted to the first 3.5 EFi (non catalyst equipped) Range Rovers from 1986, is similar (though not identical) to the system fitted to the Rover SD1 Vitesse, the main difference being the ECU (electronic control unit). The hotwire type, fitted to later 3.5, 3.9, 4.2, 4.0 and 4.6 litre vehicles (with or without catalysts), despite appearing quite similar, shares few parts with the flap type system.
Twin Plenum Injection
Twin plenum, or twin-throttle plenum injection, was a variation of the Lucas-L system, produced for a short period in the mid 1980s. It was intended primarily for the Group A racing SD1 Vitesses being campaigned by BL Motorsport, but found its way onto a small number of production Rover Vitesses for homologation purposes. In road-car form, it is similar to the single-throttle type in every way except for the plenum chamber and associated air inlet trunking. Of the parts that are different, most are now unavailable.
Holley & Edelbrock 4 Barrel Carbs
Finally, we supply several 4 barrel carburettor conversion kits for the Rover V8 engine:
1. The legendary Holley 390cfm carburettor. The kit includes a 390cfm 4 barrel Holley carb, with vacuum secondaries and manual choke, 3 different inlet manifold options, choke/ accelerator cable kit and chrome plated pancake filter kit.
2. The Edelbrock 4-barrel carb kit. The kit includes a 4 barrel 500cfm carb (bright finished). 3 different inlet manifold options, chrome plated pancake air filter kit and all cables.
A cost-effective bolt-on performance upgrade that is a direct replacement for twin carbs, offering many benefits. Ideal for V8 conversions too.
We also supply a range of K&N Air Filters for most applications, including 4-Barrel pancake filters.
*EOBD - European On Board Diagnostics - made mandatory by the European Union
OBD-II - On Board Diagnostics version II - US Version
In order to select the correct parts, this section will help to identify the type of carbs fitted to your engine. It is for identification purposes only.
Carb Identification - Stromberg CD175 & SU HIF
Both makes of carburettor have a silver tag - stamped with an identification number - which is attached to the carb by one of the dashpot retaining screws. Note: both RH & LH carbs have the same number but with an R or L suffix as appropriate. However, if the tag is missing, the engine number will help you to identify the carburettors, providing they have not been replaced by a previous owner (for detailed information & specification of engine numbers, please refer to the 'V8 ENGINE' section on page 5 of the catalogue).
All parts listed are suitable for saloon, sports and 4x4 applications unless otherwise stated.
All Rover SD1 3500 saloons from 1976 to 1981 were equipped with a pair of SU HIF6 1 3/4” carburettors with a manual choke. The tag number on these carbs is FZX1316R (right hand carb) or FZX1316L (left hand).
From 1982 until 1985, SD1 3500 carb engines were fitted with Stromberg CD175 carbs, incorporating an FASD (Fully Automatic Starting Device) on the side of the left hand carb. Easily identified by its blue plastic cover, the FASD is essentially a cold-start enrichment device.
Stromberg carbs have a stubby dashpot, compared to the SU’s taller version.
Finally, from 1985, the SU HIF was again fitted to some 3500 models. However, these were not the same carbs as the earlier ones, being considerably more complex in their cold-start enrichment operation and bearing the model name HIF44E (44mm being the metric equivalent of 1 3/4”, ‘E’ for electronic choke). The tag numbers for these carbs are FZX1456R (right hand carb) or FZX1456L (left hand).
Original carb TR8s are fitted with a pair of Stromberg 175CDSET carbs, with an automatic choke.
MGB GT V8
All factory built MGB GT V8s from 1972 to 1976 were equipped with a pair of SU HIF6 carburettors with a manual choke. The tag number on these carbs is AUD613R (right hand carb) or AUD613L (left hand).
Two makes of carburettor are fitted to Land Rover V8 engined vehicles as standard equipment: the Zenith Stromberg CD175 - used exclusively from 1970 to 1986 - and the SU HIF, which was fitted on some models for certain markets (alongside the Stromberg) from 1986 until carbs were progressively replaced by fuel injection.
The most obvious visual difference between the two types of carb is the dashpot; Strombergs having a stubby dashpot with the 'Zenith' name cast into it, while the SUs have a much taller dashpot without any markings.
Please refer to the beginning of the V8 Engine section on for information on 'Detoxed' or 'Non-detoxed'.
3712 4x4 vehicles from 1970 to 1986: non-detoxed engines - 355 suffix C, D & E
3881 4x4 vehicles from 1970 to 1986: non-detoxed engines - 3550000F to 35542952F
3915 4x4 vehicles from 1970 to 1986: non-detoxed engines - 35542953F onwards
3915 4x4 vehicles from 1970 to 1986: non-detoxed engines - 13D, 18D, 10G
3318 4x4 vehicles from 1970 to 1986: detoxed engines - suffix A & B
3677 4x4 vehicles from 1970 to 1986: detoxed engines - suffix C & D
3887 4x4 vehicles from 1970 to 1986: detoxed engines - suffix E
3854 4x4 vehicles from 1970 to 1986: detoxed engines - suffix F
3999 4x4 vehicles from 1970 to 1986: detoxed engines - 34183127F, 20D & 21D, 11G
3881 4x4 vehicles from 1970 to 1986: detoxed engines - 398
4104 4x4 vehicles from 1970 to 1986: detoxed engines - 11D,15D,16D, 17D & 19D
4185 4x4 vehicles from 1986 onwards: non-detoxed engines - 28D, 29D, 14G, 20G
4187 4x4 vehicles from 1986 onwards: detoxed engines - 26D, 27D, 15G, 21G, 24G
4186 4x4 vehicles from 1986 onwards: detoxed engines - 30D
FZX2006 4x4 vehicles from 1986 onwards: non-detoxed engines - 28D, 29D, 14G, 20G
FZX2011 4x4 vehicles from 1986 onwards: non-detoxed engines - 27G
FZX2005 4x4 vehicles from 1986 onwards: detoxed engines - 26D, 27D, 30D, 15G, 21G, 24G