TR Throttle Bodies & Parts

Our Reconditioning Process

We manufacture all of the parts necessary to enable us to fully recondition TR5 and TR6, CR and CP throttle bodies using new spindles, detachable lever arms and brightwork. We also make a CR to CP throttle linkage conversion kit – for more details click here. Our reconditioning process includes:

  • Stripping of throttle bodies
  • Bead blasting and ultrasonic cleaning of castings
  • Inspection of castings for severe pitting, cracking or damage
  • Skimming of manifolds flanges to remove high spots/distortion
  • Installation of Helicoils where required
  • Reaming of spindle bores to remove any high spots or carbon
  • Fettling and installation of spindles – these are a few thou oversized which is usually more than enough to take up any wear
  • Precision alignment of butterflies to ensure a proper seal with carbon removed.
  • Securing butterflies with new screws and high strength thread lock
  • Fitting of new return springs and lever arms. Note – all throttle bodies are fitted with earlier style lever arms that enable future arm and spring replacement without disturbing the butterflies
  • Fitting of replated or new intake pipes, balance pipes and blanking plugs
  • Installation of new or replated idle air valves
  • Installation of new or replated hose connectors and blanking plugs
  • Attachment of new stainless injector keep plates
  • Standing back and admiring how good they look – it puts a smile on my face every time!
  • Running up on test engine to ensure butterflies seal and an acceptable tick-over is obtained from day 1. Off the shelf exchange units have a sheet with performance data for each butterfly and tick-over for the set. When reconditioning customers throttle bodies a video of the test is supplied – see here.

Additional Options For Reconditioning

CP Throttle Bodies – Butterfly spindles running through a sealed bearing installed in the casting at the lever arm end. The wear on spindles always starts here and is then passed on to the middle and then far end of the spindle. If you stop the wear starting at the lever end, you stop it all. If you have bearings installed, detachable lever arms are a must to enable the levers to be replaced when they eventually wear. I fitted a set of these bearings to my own car 10 years ago, I’m on my second set of lever arms but still no wear on the spindles!

CR Throttle Bodies – Butterfly spindles running through bearings at each end which prevent future wear and play forever. This makes set up a breeze and you can have a good low tick-over and synchronised operation of all 3 throttle bodies. The only parts that are likely to wear are the butterfly lever arms and the swivel posts on the linkage rods. We make the lever arms removable and supply new replacement arms and linkage rods. We also fit the often overlooked return spring on the middle throttle body!

Note: all of our throttle body castings are supplied in bare metal as original. Paint is not applied to conceal any defects or repairs.

Throttle Bodies, Parts and Prices

Reconditioned Rare and Early TR5 Throttle Bodies

Refurbished Original TR5 Throttle Bodies

Rare as hen’s teeth. Most fully restored TR5s sold as concourse have TR6 throttle bodies fitted! These throttle bodies come complete with a new early type idle air valve. Refurbished to original spec with spindles running directly in the castings and original keep plate threads. Idle air valve can be removed and sprung screw adjusters fitted to lever arms if you want the early original TR5 set up. £150 trade in for your CP throttle bodies if they are suitable for reconditioning.

£1,200 outright sale

Reconditioned TR6 CP Throttle Bodies

Throttle bodies are supplied in matching sets. We have stocks of 1DD bodies originally fitted to late TR5 and early TR6, and later DD2, 3, 4 etc. fitted to later CP TR6 cars. Throttle bodies can be supplied with correct lever arms for Mk1 and 2 2.5PI saloons. £150 trade in for your CP style throttle bodies if they are suitable for reconditioning. Price excludes machining of bodies and fitting of sealed ball bearings – this is available for an additional £100.

£650 outright sale (£750 with bearings fitted)

Reconditioned TR6 CR Throttle Bodies

Throttle bodies are supplied in matching sets. They are fitted with new spindles with plated removable lever arms on each end. This enables bearings to be fitted (additional £200 per set). As the bearings will eliminate all future wear on the spindles, it also allows the levers to be replaced without disturbing butterflies in the future. £150 trade in for your old throttle bodies. New linkage rods and throttle and fast idle choke mechanisms are also now available to make it work better than when new. Alternatively you could fit a set of our converted CR throttle bodies that use CP linkages and countershaft – see upgrades page.

£650 outright sale (£850 with bearings fitted)

TR5 Idle Air Valve

TR5 Idle Air Valve / TR5 Air Bleed Valve and Fittings

TR5s were supplied without idle air valves. Tick over was obtained using set screws on each butterfly spindle lever.

However, this was not an effective system and dealers retro-fitted factory supplied idle air valves. These took air from a hose connector installed behind the air filter. There was only a single hose connection of TR5 plenums.

TR5 Idle Air Valve Connected

These idle air valves have been made to the original specification and can be fitted to those 5s that never had one originally, or can be used to replace the TR6 idle air valves that have been fitted to many 5s.

If you are fitting one to a TR5 for the first time, we can also supply a hose connector that can be installed behind the air filter as original. If you are replacing a TR6 idle valve we can supply a hose that enables connection to the TR6 plenum as above.

TR5 Idle Air Valve Remanufactured – £100

TR5 Idle Air Hose Connector for Installation in Air Filter Holder – £15

TR5 Idle Air Valve to TR6 Plenum Air Hose – £20

TR6 Idle Air Valve / TR6 Air Bleed Valve

Remanufactured in brass as the originals except our bodies are turned on the lathe rather than cast. Supplied with zinc yellow passivate adjustment screw and spring.

TR6 Idle Air Valve Remanufactured – £75

CP Butterfly Spindle Return Springs

Original specification butterfly spindle return springs. Galvanised finish with uniform factory finished ends. Made for us by an established British spring maker.

CP Butterfly Spindle Return Springs – £21 for set of 3

CP Butterfly Spindles

Original butterfly spindles are 5/16″ (7.95mm). We make our own butterfly spindles in house from 8mm brass rod which is 0.05mm bigger than standard. These fit our bearing upgrades but also allow us to take up any wear when refurbishing throttle bodies to original spec. Whilst this doesn’t sound much, each spindle has to be fettled to fit each manifold. They are not a direct fit for original spindles. As such, our butterfly spindles are not for resale.

CR and CP Butterfly Spindles – workshop use only, not for resale.

Butterfly Spindle Lever Arms

Early CP bolt on butterfly spindle arms. Laser cut and plated. Set of 3. Made to original spec so can be used with your existing spindles. Those for early cars are drilled and tapped as per the originals.

Set of 3 CP Butterfly Spindle Lever Arms – £30

Manifold Brightwork

If you are rebuilding your own throttle bodies, why not replace the shiny bits. Replated or new inlet pipes, balance tubes, hose connectors and blanking plugs for CP and CR throttle bodies. Rather than throw away the old inlet tubes and balance pipes, we have tools that can remove them without damage. The same goes for the hose connectors, if they are undamaged and uncorroded, we blast and polish them before sending them off for replating. If any are not suitable for re-use or missing we make new.

Manifold Brightwork – £75 (if hose fittings and blanking plug are exchanged)
Manifold Brightwork – £100 (outright sale)

Injector Keep Plates Stainless Steel

Stainless steel injector keep plates, bolts and spring washers. Set of 3. Note our bolts longer than standard to spread the load over all of the threads in the casting.

Set of 3 Stainless Steel Keep Plates, Bolt and Washers – £24