T3 Conversion

Converting your FRST to a T3 is one of the best ways to increase power and potential power of the car. The larger size of the turbo flows more air and also provides more of a kick than the almost lag-less T2. The T3 provides more mid range than the T2 and maintains boost higher up the rev range than the T2, which has a tendency to tail off above 5500rpm. For serious power the T3 is the only way to go, but the conversion need not be expensive. The parts are available for a few hundred pounds and fitting is a fairly straightforward task.

When Ford released the Fiesta RS Turbo in 1990 they fitted the smaller T2 turbo rather than the Escort’s T3. The smaller engine bay of the Fiesta meant that the Escort turbo wouldn’t have fitted between the block and the radiator. This is the first obstacle to overcome when doing the swap. This will be explained in detail later. The conversion require a number of parts from a donor Escort or parts supplier. There are a few alternatives in certain aspects of this, such as the downpipe arrangement and oil returns. Some Fiesta parts can be modified and re used such as the cone filter if fitted.

The project car for this conversion had a K&N 57i cone filter, no amal valve, standard intercooler and a full stainless Magnex exhaust.

A certain degree of mechanical competency is required, as some parts are relatively tricky to do and some aspects of the conversion may differ from car to car. No specialist tools are needed. A Haynes manual is recommended for information on the location of bolts / fixings etc and also torque settings.

Parts Required

  • Escort RS Turbo T3 turbo (or aftermarket replacement, hybrid etc)
  • Escort RS Turbo exhaust elbow (90 degree bend mounted directly to the turbo)
  • Escort RS Turbo exhaust manifold
  • Escort RS Turbo downpipe (or aftermarket replacement, stainless etc)
  • Escort RS Turbo oil feed pipe (braided hose with threaded fittings)
  • Escort RS Turbo oil return drain pipe (metal pipe with flanged fitting)
  • Escort RS Turbo oil return elbow pipe (rubber pipe with slight bend) (FINIS: 1640090 £9.95+vat)
  • Escort RS Turbo water feed pipe
  • -31 or equivalent actuator (a new one is preferred)
  • two (11mm usually) nuts to fit the actuator thread
  • 2”-3” of alloy / stainless steel pipe (if you don’t want to cut the FRST crossover pipe)
  • FRST 90 degree turbo to crossover pipe (if you don’t want to cut up your existing one)
  • FRST air filter to turbo pipe (if you don’t want to cut up your existing one)
  • FRST or ERST cone filter, if you want to keep the air box see below
  • 4 extra 50-70mm hose clips

Removing the T2 and positioning the T3

Start by removing the front bumper and radiator fan, then drain the coolant and undo the boost, turbo water feed and radiator hoses to enable the radiator and intercooler to be removed. To provide easier access to the front of the engine it’s a good idea to remove the bonnet catch and support bracket. Lift the radiator and intercooler out of the front of the car. Remove the plug leads and plastic lead divider and undo the T2 heat shield and aluminium crossover pipe. Unbolt the T2 oil feed pipe which runs from the back of the block by the oil filter to the top of the turbo. There is an earth lead which runs from the engine carrier hook to the suspension turret so ensure this is refitted after removing the oil feed bracket. Unbolt the oil return from the middle of the block leaving just the threaded section protruding. Disconnect the hoses from the actuator to turbo or actuator and turbo to amal valve (depending on setup). If the car has an amal valve label the hoses to avoid confusion. Undo the downpipe from the turbo and remove the downpipe from the exhaust centre section. This should now leave the turbo completely disconnected from everything and ready to remove.

Undo the exhaust studs on the head and lift the turbo off the engine. If the T3 isn’t already bolted to the manifold and elbow, connect it now. Position the T3 over the studs and tighten to the specified torque settings. Fit the actuator but leave the rod disconnected from the wastegate, we’ll set the boost later.

Oil feed and return

Screw the braided oil feed pipe into the block, the block end is the one with the slightly longer metal L bend before the braiding. Route the pipe round over the gearbox side of the engine taking car to keep it away from rubber pipes etc. Position it near to the top of the turbo but don’t connect it yet. Fit the oil drain return pipe and then use the rubber oil return pipe to join the drain pipe to the threaded boss on the block by sleeving it over each one. Use hose clips to tighten the seal, making a mental note to tighten them again after running the car the first time, when they have softened with the heat. This will ensure a good, tight seal. Another method is to remove the threaded boss from the block and use the Escort fitting which is just a push fit.

Water feed and return

The T3 water feed pipe is further away from the radiator so the Escort pipe is needed. It should be possible to connect the T2 return pipe to the T3 as the connections are roughly in the same place. A little trimming of the hose may be required.

On our project car we removed the water cooling to the turbo. This has the advantage of allowing the car to run cooler, as the water is not passing through the hot turbo. The downside to this is that the car must be allowed to warm up and cool down properly before and after use, which can be inconvenient for short journeys. To disconnect the water cooling it is necessary to block the takeoff on the side of the radiator and on the radiator top hose. An Escort Series 1 top hose will suffice for this as they run no water cooling.

Boost hoses

The existing charge carrier (T U R B O pipe) to intercooler hose is fine but the turbo to intercooler outlet on the T3 is in a different place to the T2 so a new pipe work arrangement is needed. Take the 45 degree bend that connected the turbo to crossover pipe and cut this into two pieces so each will provide a 45 degree bend rather than the full 90. Detach the intercooler from the radiator and position it in place with the mounting foot on the base resting on the front cross member, forward from it’s accommodating recess. Use the 2-3” metal pipe, or a similar length cut from the crossover pipe, in conjunction with the two 45 degree bends to connect the intercooler outlet to the turbo. It’s usually trial and error with the length of the pipe to obtain a good fit.

The FRST cone filter can be re used. Take the air filter to turbo hose and cut the bottom right angle off it to leave an L shape. Trim it back so the narrower end sleeves over the turbo then hose clip this in place with the filter pointing down towards the gearbox cradle. A preferable arrangement is to relocate the battery to inside the car then use a straight hose to position the air filter where the battery was. This reduces its susceptibility to dirt and water.

It is possible to re use the standard air box, but as the air intake on the T3 is on the opposite side to the T2, pipe work will need to be run across the engine bay, or the air box will need to be relocated to the opposite side of the turbo.

On our project car we used the original Ford hoses to avoid cutting up the Samcos. The car will be fitted with a different intercooler shortly and had we been continuing to use the standard unit we would have used the Samco hoses.

Exhaust Downpipe

There is a degree of variation in this area depending on the diameter of the downpipe used. The Mongoose downpipe used for our project car was just big enough to sleeve neatly over the Magnex centre section so it was trimmed by around 4” and slotted then clamped over the top. The downpipe had to be bent slightly to avoid contact with the front suspension support bracket that runs under the engine.

An alternative method is to cut both the Fiesta and Escort downpipes and weld the two together in a suitable place to allow the system to mate up correctly.

Setting the actuator and priming the turbo

Fill the turbo with oil through the oil feed hole then position the end of the oil feed pipe into a clean glass jar. Remove the fuel pump fuse and crank the car until oil is visibly flowing through the pipe. Refit the fuse and connect the oil feed pipe to the turbo. Empty the oil back into the engine.

It’s advisable to get the car set up on the rolling road to ensure it’s boosting to the require pressure and that the fuelling is set correctly. If the car doesn’t have a boost gauge, either buy or borrow one before proceeding or set actuator not to boost by winding the rod out to it’s maximum length to hold the wastegate open constantly. If the car has a boost gauge the boost can be set now. To make adjustments easier fit the two nuts onto the rod and lock them against each other at the end of the thread. This will allow the actuator rod to be turned with just a spanner rather than trying to turn it with pliers. Wind the actuator rod to such a length that it needs to be pulled open slightly before it will hook over the wastegate. Reconnect the pipe from the turbo to actuator or the amal valve as required.

Moving the radiator

If the radiator is left in its original position the actuator bracket or actuator itself will be either touching the radiator or very close and likely to make contact when the engine is running, damaging it. In order to eliminate this possibility the radiator and intercooler need to be moved forward by approximately an inch. There is some variation here depending on the car, and also the turbo and actuator used may provide less or more clearance depending on their design.

Undo the hose clip connecting the intercooler to the bottom hose and attach the intercooler to the radiator. Position it in place but with the locating feet at the bottom moved forward of the retaining recess in the cross member. This will position the two at an angle and should clear the actuator bracket. If more clearance is needed it may be necessary to cut a notch out of the vertical panel by the headlight, where the turbo water feed is taken from the radiator. Cut a notch to allow the radiator to be moved forward without the water takeoff fouling the panel. Repaint any bare metal to avoid corrosion. Remove the inner rubber washer from the slam panel mounts to allow the radiator to be secured nearer the front. Reconnect the intercooler to the turbo and charge carrier pipe.

Maximum clearance can be obtained by mounting the radiator at an angle with the intercooler sat slightly behind it. This is at the expense of visual appearance though and can look odd. A happy medium can be obtained by experimentation.

The first run

After reconnecting the water hoses, plug leads etc the car is ready for a test run. Keep an eye on the boost gauge and make adjustments if necessary - shorten the rod to increase boost, lengthen it to decrease boost. After the run allow the car to cool down until the hose clips around the pipes can be tightened further. The oil return has a tendency to leak if not tight. If everything appears to be in order the next step is to get the car tuned by a specialist. This will ensure the fuelling and boost are correct and the car is not detonating.


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