skip to Main Content
Select Currency:

4AGE to J160-S (3S Beams) installation guide

4age to J160-S (3sge Beams) gearbox adapter kit-646

This kit allows a J160 gearbox to be installed onto a Toyota A-series engine. When using our kit, the gearbox doesn‘t need any dissasembly to be fitted. However, depending on the vehicle you’re installing it into, it‘s likely that the external ribs on the bellhousing will need to be ground down as well as the top of the bellhousing being modified for clearance. For more information on this and other relevant information, we recommend you read the following information thoroughly to make sure you order all the parts you need in on go. A comprehensive guide on installing all the necesary parts and in performing all the modifications necessary for this swap is well documented on the.

Canadian Old School Toyota site, Dorikaze.

Installation notes

– An impact / rattle gun should not be used to do up any bolts, these can easily cause over-tension and damage the threads of this adapter.

– To avoid mix ups it’s highly suggested to not empty out all of the individual fastener bags until they are required.

– The supplied fasteners may differ from what is pictured in the photos.

– Some spare washers are included.

Flywheel options

– All of the original 16 and 20V 4age / 4agze flywheels can be used with this adapter, this includes both of the 4agze models (225 + 230mm).

– The early 16V Bigport engines used a flywheel with a 200mm diameter friction disk, while the later 4age engines used a 212mm. Both of these can be used if the matching clutch is fitted, but the larger 212mm type is suggested. Also some clutch companies quote the 212mm size to be 215mm.

Clutch options

A 4AGZE flywheel and clutch kit can be directly used as is with this kit, however the thrust bearing that is provided in 4AGZE clutch kit is not compatible with our adapter kit. For those using a smaller diameter 4AGE flywheel, please see below.

– Clutch pressure plate: The pressure plate needs to be the matching type / friction diameter for the flywheel being used. If you’re using a 200mm flywheel, then use a 200mm clutch pressure plate, and the same goes for the 212mm one too.

WARNING: You need to use the the same pressure plate and the same type of friction disk. A pressure plate intended for a disk that uses an organic compound shouldn’t be mixed with a multi-puck or button disk. If unsure, call up the clutch company to confirm compatibility. Better yet, buy your clutch and pressure plate as a kit from one manufacturer.

– Friction disk: See the part numbers in the next section and choose a clutch that suits your needs and driving style.

– Clutch fork, Slave cylinder and Retainer clip: These three parts are OEM parts from the J160 Gearbox and should be reused.

– Clutch carrier + Thrust bearing: A custom thrust bearing carrier is supplied as part of the kit. This is compatible with the original J160 clutch fork and retainer clip but instead uses a different thrust bearing. The compatible bearing is the same type as used on both T50 and W5x model gearboxes. This is not supplied and we instead offer this as a separately sold part in our store.

Compatible clutch part numbers – 200mm

– Friction disk option 1 – organic: Exedy: TYD126UF
– Friction disk option 2 – 5-button: Exedy: TYD126B5 – needs a pressure plate intended for a button disk.

Compatible clutch part numbers – 212 / 215mm

– Friction disk options: Exedy: TYD034U
– Pressure plate option 1
– Heavy duty: Exedy: TYC549HD – Rating: 490kg clamping force
– Pressure plate option 2
– Extra heavy duty: Exedy: TYC613HD – Rating: 680kg clamping force

Starter-motor compatibility

Starter-motors can be mounted to adapter on the intake or exhaust side of the engine. A blanking cover is supplied to cover the unused side. There are many different starter models that are compatible, but some can only be used on one side of the engine. You can use:

– Those originally compatible with a T50 gearbox

Our Starter-Motor upgrade adapter that uses a Honda Starter (Exhaust side only)- some of those that where originally used on the earlier front wheel drive gearboxes.Depending on the model, it may only be able to be used on the intake side of the engine.

– Of these types above, there are two different variants as shown below. Pictured on the right, is one that features a pinion support as part of the housing. The model on the left doesn’t use a support. If the starter being used:

– Doesn’t have a pinion support

– Will be mounted on the intake side, and

– Isn’t one of our Honda starter adapters, then skip the next section completely as there are no bellhousing modifications required. For everything else see below.Note: When fitting a starter-mottor to the intake side of a 20V 4AGE engine, the intake-side engine block to throttle body support braces can’t be fitted.

Bellhousing modification (Starter-motor clearance)

To go about performing the necessary bellhousing modifications, follow the steps below. To make this process significantly easier, it’s best to fit the adapter plate on to the gearbox by itself and then test the starter clearance. It’s easier to fit everything together on a bench than while under your car. Once the modification has been made to the bellhousing, clean up the metal particles and bolt the adapter plate to the engine.

Starter fitment: To fit your starter, you’ll need to use a die grinder. There needs to be sufficient clearance for the static fitment of the starter. For those that have a pinion support as per the following picture this is all that’s required. However, with starters that don’t have the pinion support (including our upgrade adapter that uses a Honda Starter motor) they need additional room because the pinion will move outwards during activation. Therefore, during the test fit, the starter’s pinion needs to manually activated. This can be done a few ways. Some 4age starters have a rear facing cap that can be removed, while on others, the solenoid can be removed, after which it can be manually pushed out. Once the pinion clears the behousing, hook some jumper cables to the solenoid to check for interference.

Bellhousing modification steps

– Slide the adapter plate on to the gearbox bellhousing face. There are two dowels that stick out of the adapter plate that will locate to the holes in this face. Once located, use a soft hammer or a steel hammer with a block of wood to tap the plate until it sits flat against the bellhousing surface. Bolt the adapter to the bellhousing.

– Line up the mounting holes between the Starter and the plate to test fit, then roughly mark where the material needs to be removed.

– Remove the adapter plate and grind into the bellhousing as marked out.

– Bolt the starter to the adapter plate and check for manual clearance for the pinion. If there is interference, then grind more of the belhousing away. Once there’s no interference, you should live test your starter with jumper leads.

– Once the starter has successfully been fitted and tested, proceed to the next section

Gearbox / Engine Preparation

– Read our J160 Gearbox conversion guide for information on the necessary modifications needed for body and fuel line clearance.

– Remove the existing starter, gearbox, clutch, flywheel, spigot bearing, dust shield and the engine to bellhousing braces. For help on how to remove the old spigot bearing, read our article on the subject.

– Inside the bellhousing of the J160 gearbox, remove the clip from the thrust bearing / carrier and the clutch fork. Then slide the carrier off, as it isn’t re-used.

– If you’re using one of our Gear stick relocaction kits, then only fit the rear extension on the shifter shaft The housing that comes with this kit is best installed through the hole in the floor later on after the gearbox is fitted into place.

Clutch Thrust-carrier, Thrust-Bearing and Fork

– The original J160 clutch fork and retainer clip are reused. However a thrust bearing is the same as the type used on W5x / T50 gearboxes

– Apply grease to the inside of the supplied thrust carrier filling up the grease trap groove. Once done slide the carrier on to gearbox guide tube.

– The clutch fork is to be pushed onto the carrier, this and the retaning clip must be fitted as per the orientation in the picture below. Here is a demonstration of how the carrier, clip and fork should fit together. The clip has been painted purple for ease of visibility, but is normally a dull black colour. The clip has been painted purple for visibility but is normally a dull black colour.

Adapter and Sandwich plate fitment

The engine block should have two locating dowels fitted into it, should any be missing then they must be replaced.

– The engine dowels must protrude out less than 12mm from the rear face of the engine block. If they do then a normal hammer can be used to tap them further in.

– Fit the thin steel sandwich plate on to the engine block. This plate will locate to and slide over the two original engine block dowels.- Just as the above the main adapter plate is fitted directly behind in the same way. This also locates to the same dowels but is a much tighter fit, use a soft hammer or a steel hammer with a block of wood to tap the plate until it sits flat against the bellhousing surface. There is a chance that initially the plate will not sit perfectly flat, this is no problem as it will straighten itself out once everything is assembled.

– When the two plates fitted check the dowels from the engine block. These must not stick out past the surface of the adapter plate at all, if they do remove both plates and use a hammer to knock the dowels further in. See the picture below as an example of a correctly fitted dowel that doesn’t protrude.

– Open the “Adapter plate to engine block” fastener pack. These bolts do not use washers and fit through the plates and tighten up into the engine block.

– Fit the four large hex bolts through the holes in the adapter plate to clamp it down, one bolt is for each corner of the engine block. Each one of these fits into a recess in the adapter plate as pictured above.

– Repeat the process above with the small button head bolts, these are located closer to the middle on the flat lower step of the plate.

– Tighten all six bolts, installed they should look like the picture below.

Spigot bearing extension install

Included is a spigot bearing extension, this needs replaces the original spigot bearing in the crankshaft end. This needs to fitted in place without hitting the middle of the bearing. A common method is use a socket tool that has an outside diameter a little smaller than the 28mm of the spigot extension, place the socket over it and lightly tap it until the extension bottoms out in the crankshaft recess.

Starter-motor fitment

For the mounting of the starter motor three bolts are supplied, only two of these are used. Which two will depend on which side the starter is mounted, see below. Choose the relevant choice below and tighten the starter into place. These bolts are to be fitted through the plate without washers.

– Exhaust / original side: Use 1 x Custom Cap head + 1 x Hex head.

– Intake side: Use 2 x Hex head.

Starter-motor blanking cover fitment

The unused Starter-motor mounting hole is covered with a supplied blanking plate. Use the two short button head bolts to go through the adapter plate and the blanking cover to then tighten into place using their matching flange nuts on the outside. The bolt heads each sit in a recess in the the adapter plate.

When the plate is covering the hole on the intake side it must be arranged as it’s pictured below. This is where the notch clears the visible threaded hole. For the exhaust side any position is fine.

Engine block brace and Sandwich plate to adapter plate

Originally there are cast iron supports that goes on both sides of a 4A engine when fitted to a T50 gearbox. Using this adapter only the exhaust side brace can be used and it is suggested to do so.

– Loosely fit the two original bolts through the brace into the engine block.

– Using their matching washers fit the suppied bolts through the brace, Sandwich plate and wind them into the adapter plate. Tighten up all four bolts of this brace.

WARNING: The fitment of washers is mandatory with these bolts or else they will protrude out the other side of the adapter plate. See the picture below.

NOTE: Pictured is the earlier model of adapter plate which has some visible differences such as an additional bolt which is no longer part of the design.

– Use the remaining bolts and washers to fasten the bottom of the sandwich plate to the bellhousing.

Flywheel and Clutch

At this stage both the flywheel and the complete clutch assembly can be fitted. First fit the flywheel and do up the bolts finger tight. Replacement bolts are available through our store. Our 4AGE flywheel / ring-gear locking tools can be used to stop the engine from turning. To do so temporarily undo the top two main adapter plate to engine block bolts. Then fit the tool into place using the supplied bolts but without the spacers. The flywheel bolts need only be finger tight to use this tool, so therefore it can even be used to properly tension up both the flywheel and clutch bolts. Once done remove the temporary bolts and tool to then refit the adapter plate to engine block bolts.

– Slide the Flywheel on and wind it’s bolts in.

– Tighten these flywheel bolts in several stages up to a final tension of 75Nm / 54 Ft-Lbs.

– Fit the clutch friction disk and pressure plate in place.- Locate the friction disk with an alignment tool before tightening the pressure plate bolts to the correct tension.

Gearbox fitment

The gearbox can now be installed into the car. If this is being fitted into an AE86 then it will not be required to temporarily drop the engine crossmember for clearance to fit the gearbox onto the engine / clutch.

If one of our Gear stick relocaction kits is to be used then only fit the rear extension on the shifter shaft, the housing that comes with this kit is best installed through the hole in the floor later on after the gearbox is fitted into place.

– Use the standard procedure gearbox installion procedure for a gearbox to fit it into place. Once lined up correctly the gearbox bellhousing will slide over and locate to the adapter plate dowels.

– Only once the Bellhousing face is flat against the adapter plate all the way arund then use all the matching washers to fit and tighten the supplied bolts from the “Bellhousing to adapter plate” fastener pack.

NOTE: Two of the mounting holes in the bellhousing are not used with this adapter, this causes no ill effect at all.