Transmission parts for 105 Series Coupe Alfa Romeo

We provide a service to rebuild your gear box – please contact [email protected] for more details.

Full set of components required to rebuild all moly-synchro type 105 series gearboxes.

Please specify if you need a layshaft front bearing of 20mm or 25mm internal diameter.

These synchros are not compatible with the S1 of mechanical gearboxes (1963-1966) which featured non-moly synchros.

Full kit of parts to convert an early (101 & early 105) non-molybdenum synchromesh “yellow label” gearbox to later improved molybdenum coated synchros as per late “red label” gearboxes.

A great upgrade when rebuilding any early gearbox with grooved synchos.

These synchro rings have been used in multiple championship winning cars including our U2TC FIA 1600 GTA.

Designed to give a faster and smoother gear change than was possible with genuine OEM Alfa rings to make a product more suitable for competition use. OEM synchro rings took time to bed in and get a fast and smooth gear change; typically period of time in which 300-500 miles would be covered.

Of course for competition use, 300-500 miles bedding in period is not ideal and the last thing you want is a slow gear change in qualifying on a freshly installed gearbox. Realistically a typical race gearbox will only see 500-1000 miles between scheduled maintenance rebuilds or a competition rally car 2000-5000 miles.

The design of our synchro ring will ensure perfect gear changes from the very first gear change leaving the pit lane and regular servicing our our works cars over the past 8 years have proven a life span well exceeding those typical service intervals.

OEM moly-coated synchro ring for use on restoration and road cars.

For competition use, we recommend our competition synchro ring for a faster action gear change.

Standard quality. For track day and competition cars we recommend using our own premium quality production above this listing.

Synchro sleeves developed to match our synchro rings.

By cutting up one of our new ‘old stock’ original Alfa synchro sleeves and scanning the tooth profile, we were able to produce a CAD drawing to perfectly replicate the original production. With this data on file we were able to manufacture these hardened sleeves.

Fit these with our synchro rings for a full perfect matching original specification synchro system.

Internal synchro strap for 1^st gear, 1 required. We have made these to replace the often damaged part found fitted inside the synchro assembly. Typically these just get reused each time the gearboxes get rebuilt, but they are now getting to an age where these are simply damaged and will not allow the synchro to operate as it should.

Gearbox break sector  for 1st gear to suit all 105 gearboxes. 1 needed per box.

Gearbox brake sector for 2nd, 3rd, 4th & 5th gears to suit all 105 gearboxes. 4 required per gearbox.

Gearbox reference sector to suit all 105 gearboxes. 5 required per gearbox.

Internal synchro strap for 2^nd, 3^rd, 4^th & 5^th gear, 2 required per gear. We have made these to replace the often damaged parts found fitted inside the synchro assemblies. Typically these just get reused each time the gearboxes get rebuilt, but they are now getting to an age where these are simply damaged and will not allow the synchro to operate as it should.

We are increasingly finding bent selector rods more and more when we are rebuilding gearboxes.

Resulting in sticky gear change but also causes the selector fork / synchro sleeve not running straight to the gear assembly which can cause premature wear, damage and more gearshift quality.

They have proven very tricky to try to straighten and since the huge success of our manufacturing of billet 3rd / 4th gear selector rods we have now evolved this into a full set of 3 rods manufactured from motorsport grade materials and machined to motorsport quality tolerance.

We have also improved the design of these to be tougher and stronger, 3rd / 4th rod is an inherently weak part in the gearbox, the narrow width required as part of the gearbox design means that the clevis where the gear linkage drops into can easily get bent from ‘over-selecting’ gears.

This risks a shift not fully selecting a gear and resultant massive gearbox damage.

We have re-designed the part with greater radiuses and increased material thickness at the weak points to make the part more resilient to this ‘over-selection’ based driver damage.

Worn/damaged selector forks are becoming a bigger and bigger issue with Alfa gearboxes as they get older and increased performance & race use is highlighting the inherent design weaknesses of the standard parts. We have redesigned and manufactured these race quality forks by combining our considerable experience of high performance & motorsport use along with general modern motorsport knowledge to produce the ultimate selector fork set of 105/115 series gearboxes. We have added an additional pressure pad to control the synchro sleeve angle more accurately and to increase the total pad area and thus reduce pad wear rate, the net result is a sweeter and faster shift action. These forks are made of motorsport grade steel, so are also more resilient to abuse from over selecting than the factory bronze parts. As developed for and being used in our latest GTA-R builds.

Gearbox detent springs to suit all 105 series gearboxes. Priced individually, 3 required per car.

Input shaft bearing 101.00.13.223.00, early type retained by circlip.

Input shaft bearing 105.12.13.223.00,  late type retained by nut.

Fits in back end of input shaft, to mate to mainshaft.

For 1300/1600/1750. 25mm centre bore.

2000 version with 20mm centre bore – 105.12.13.224.00

For 1300/1600/1750 – 101.00.13.223.00

2000 version of above – 105.12.13.223.00

Mainshaft rear bearing to suit all 105 series cars.

Standard production 105 series reverse idler gear.

Bronze inner bush for gears.

Gearbox tail mount to suit all 105 series car with a hydraulically operated clutch.

Correct more solid bush for early cars 1964-1967. Can also be used as heavy duty item for late 105 and competition cars.

Large gear lever turret washer to suit all 105 series cars.

Fits over tunnel before steel pressed top hat gets screwed on.

Gearbox inner rubber gaiter. Fits over the rear ‘tower’ of the gearbox where the gear lever attaches to the gearbox on 101 and 105 Series 5 speed gearboxes. Fitted to all mechanical clutch cars and hydraulic clutch up until the early 1970s.

Fits over the steel top hat that bolts to the transmission tunnel

Clamp for gearshift rubber gaiter-correct size to fit inner gaiter to the gearbox top.

Combined version of above 2 gaiters – for use on cars with metal collar integrated into transmission tunnel.

Ball bearing for cars with a push down gear lever. Two needed per car.

Fits under gear lever to seal the gearbox and stop the gearbox top washers rattling!

Fits under gear lever.

Replacement gearbox layshaft and main shaft end ‘stake’ nut to fit gearboxes used from 1972 onwards. Due to gearbox interchangeability, you will need to check if your gearbox has a stake nut like this or a tab washer and regular nut.

For gearboxes with reverse light mounted int top of bellhousing via bracket, bell housing will have oval hole where selectror rods poke through. (1963-1974 approx).

For car with reverse light that screws into end of bellhousing – no oval hole for selector rods to poke through. (1974-1993).

Lightweight stainless steel transmission fill and drain sump plug.

We have made the plug with a cross drilled head making it simple to lock wire.

Transmission drain & fill plug (Allen head type) as used in the Alfaholics workshop.

Magnetic oil filler sump & fill plug.

Gearbox oil warning sticker copied from an original.

Most rear propshafts have had many Universal Joint changes in their life and as a result can often have damaged Universal Joint housings, this means that even with new Universal Joint vibrations can still occur due to end float in the Universal Joint housings which is beyond shimming out. The sliding joint is also another area for wear on an original unit that of course cannot ever be repaired. As a result of these 2 major factors we no longer use rebuilt rear propshafts in our workshop, fitting only our brand new unit for 100% perfect results at virtually no extra cost to the customer. We manufacture these units from race quality thin wall 2” tube, not only does this mean that the tube is stiffer which results in far smoother running at high speeds, but it is also much lighter than an original unit. We have also increased the size of the Universal Joints on each end which makes them much less prone to wear and much more able to handle the load from engines with increased performance. Each prop is dynamically balanced to 8,000rpm meaning that this item is perfect for use on both road and competition cars.

Steel Bush for front of propshaft to centre propshaft inside doughnut.

Small nylon plug that fits inside the ‘top hat’ bush that fits into the front of the propshaft and receives the output shaft from the gearbox.

Fits onto end of gearbox output shaft to keep dirt out of the front bush.

For cars with late propshaft centre supports – 1968-9.

Early version with grease nipple (1964-67).

For cars 1964-1967.

CNC machined aluminium propshaft centre support complete with early style rubber and pressed in premium bearing.

To suit all S1 105 cars with early propshaft centre support, with bearing carrier separate to support rubber (1962-1967).

CNC machined aluminium propshaft centre support bearing carrier.

To suit all S1 105 cars with early propshaft centre support, with bearing carrier separate to support rubber (1962-1967).

Heavy duty version of late support, ideal for track day and race cars.

For all cars 1968-1993.

For all centre supports.

Premium propshaft centre bearing, ideal for fast road and competition cars.

Propshaft centre bearing retaining circlip.

Used on all 105 series cars as well as 750 & 101 Series.

We recommend replacing the circlip when you fit a new centre bearing.

Standard version.

Heavy duty version for fast road and track day cars. For race cars see our race propshaft conversion under Race & Performance ‘Transmission’ section

Automatic Propshaft Coupling for Montreal & S4 Spider.

Propshaft to axle nut for 2000 cars.

Propshaft to axle bolt for 2000 cars.

8mm nut for the propshaft to axle.

Full kit of pinion and differential case bearings, pinion oil seal, differential sump gasket, rear wheel bearings and halfshaft oil seals.

To fit all non-limited slip differential axles (Sprint GT/GT Junior & 1750 – 25 spline halfshafts).

Late model cars have press on shrink rings rather than screw on shrink rings, please check on post 1973 cars and order shrink rings separately if required.

Full kit of pinion and differential case bearings.

• Pinion oil seal
• Differential sump gasket
• Rear wheel bearings
• Press on shrink rings
• Halfshaft oil seals

To fit all larger type limited slip differential axles (2000 GTV, Spider and Berlina – 27 spine halfshafts)

Increase the limited slip action on your Alfa ZF type limited slip by fitting these extra slip plates in LSD unit. Fitted in pairs, to replace a pair of standard spacer plates.

Differential tab washer left side. Three required per car. Priced individually.

Right hand differential tab washer. Four required per car. Priced individually.

When assembling a differential you will need to set both the pinion height (please see Pinion Height Shims listing) and the pinion preload using shims. These pinion preload shims are manufactured from high grade carbon steel by an aircraft industry approved manufacturer. These shims are used by ourselves in all of our race and high performance road differential builds.

The shims are available for both 1600 and 2000 specification differentials and available in a range of thicknesses.

• 1600 Differential Pinion Preload shims available in 0.05mm increments, from 1.20mm through to 2.80mm thick.
• 2000 Differential Pinion Preload shims available in 0.05mm increments, from 2.05mm through to 2.60mm thick.

For 1300,1600 & 1750 non- LSD axles.

For all 2000 LSD axles.

For 1300, 1600 & 1750 non-LSD axles – GRB 203.

For all 2000 LSD axles – GRB 204.

For 1300, 1600 & 1750 non LSD axles – GRB 205

All all 2000 LSD axles – GRB 206

For 1300, 1600 & 1750 non limited slip differential axles – GRB 207.

For all 2000 limited slip differential axles – GRB 208.

For all LSD axles and late GT Junior axles.

Differential tab washer to suit all small type 105 series axles.

Differential pinion nut to suit both small (1300/1600/1750) & large (2000) axles.

Differential pinion nut tool.

Halfshaft Oil Seal for 1300,1600,1750

Halfshaft Oil Seal for 2000 LSD axles, also for late GT Junior rear axles which have press on shrink rings – GRB 211.

Standard.

Replacement tab washer to suit 105 series cars with screw-on wheel bearing retaining nuts.

Much tigher tolerances for reduced ‘pad knock back’.

Standard quality bearing kit to suit both early and late 105 series cars. If you have a limited-slip differential you will need to order a late version.

Exacting tolerances with improve the tooth cut profile for increased strength over the original cut used by Alfa.

Optimum performance can be achieved by fitting in conjunction with our Alfaholics Limited Slip Racing Differential.

• 5.3 & 5.8 ratios are for intended for circuit racing,
• 4.3 option is the optimum ratio for fast road and track day cars.

By using the small size axle, unsprung and rotational weight is kept to a minimum.

An additional benefit for those people with fast road & track day cars, is that you can use the existing axle from your GT Junior and simply fit this 4.3 ratio with LSD (Limited Slip Differential), rather than trying to find what are now very rare Berlina 4.3 rear axles.

We can also manufacture to order any desired ratio (in addition to those above) within 3 weeks.

These brackets are direct copies of the original brackets welded to Dunlop axle tubes to mount the Dunlop slave cylinder to actuate the mechanical Dunlop caliper.

Laser cut and jig bent ready to weld to your axle tubes. Use these in conjunction with our “Dunlop Rear Caliper Mounting Brackets” to convert any axle to Dunlop rear brake fitment.

Heavy duty LSD oil with shock protection additives to protect LSD internals. Also suitable for dog ring selection gearboxes. As used in all Alfaholics GTA-R and race cars

Fully synthetic gear oil.

Suitable for track day and race gearbox oil.

Unrivalled shift speed, excellent synchro life.