Zetec Turbo FAQ's

There are many options on zetec-turbo-ing, and i will split it into 2 main categories i.e. "Low boost up to 10psi" and "high boost over 10psi"

if you want to run 7000-8000rpm's even on 10psi you should really think about upgrading the bottom end of the engine aswell.

a third option is swap in the whole engine, turbo and inlet manifold from a Focus RS. you will need to fit aftermarket management, get a modded downpipe and rig up a custom intercooler setup but it will save alot of hassle of turbo-ing your zetec. the focus RS gearbox will not fit straight onto the mondeo however.

on either method you will be very restricted on a mk1 or mk2 mondeo for physical space in the engine bay, so one of the first jobs is to relocate the battery into the boot to give you more room.

LOW BOOST OPTION:

For this you can do it as direct bolt-ons onto the engine, and not have to do any internal engine work.

EXHAUST MANIFOLD:

Focus RS (will need downpipe chopping fabbing up even on a blacktop)

CVH turbo manifold with studs onto head modified (this is not ideal, studs tend to come away eventually)

CVH turbo manifold with a zetec flange welded on

focus zetec turbo manifold from USA (OBX and other such companies make them)

area six manifold (very nice but very expensive)

INLET MANIFOLD:

you can use the standard inlet manifold but it doesnt flow particularly well, and was designed from the factory to perform better at low-mid rpm's

escort zetec inlet manifold - has the advantage of being able to connect to a RS turbo crossover pipe (over the cam cover) to link to the intercooler. it uses the older silvertop fuel rail and injectors. it will require some working of vac pipes and uses the older style throttle body

fiesta RS1800i inlet manifold - as per escort zetec manifold but flows alot better

rover 820i inlet manifold - requires adaptor plate to fit to the cylinder head, uses the rover throttle body, and flows very well

INTERCOOLER:

Intercooler isnt absolutely essential on a low-boost install, but if you plan on running no intercooler it would be better to keep boost down to 7-8psi ish.

SAAB 9000 intercooler - i've had this on two mondeo's and find it to be very adequate. it fits on a mk1 or mk2 mondeo very snugly (unless you have aircon) and is big enough to take 300-350bhp

Renault 21 intercooler - this is small but can take a decent amount of boost, and fits snugly onto the mondeo

there are many types of intercoolers available, be careful not to pick one too thick or it might need cutting of bumper and bodywork to make it fit. and think carefully about where the input and output hoses are going. there isnt much room under the front of a mondeo.

you can use samco IC hoses and joiners (or roose motorsport or whatever). be sure to use decent quality hose clips or you will be blowing them off all the time. a popular choice is to use a RS turbo crossover pipe "charge carrier" to route the IC pipes over the cam cover from the throttle body.

INJECTORS:

you will need bigger injectors even on a low-boost install (the standard ones max out at 155bhp). some people have turbo'd zetecs using the standard ones but this will end up with running problems, running lean and detonating (pinking)

on a silvertop fuel rail you can use certain types of nissan or subaru injectors, with zetec seals. you also need the jap wiring loom plugs

on a blacktop fuel rail you can buy bigger injectors off the shelf from manufacturers like ford racing. approx £100-120 a set.

you need to size your injectors depending on expected power output from your turbo and boost levels

TURBO:

on a low-boost install you dont want a massive turbo. think T2 or T25

you will need to run an oil feed pipe from the oil pump to go into the top of the turbo. and an oil output pipe from the bottom of the turbo, connected into the sump

most turbo's are also water cooled. you need to run water supply and returns to the turbo from the head.

MANAGEMENT:

you will need some kind of aftermarket management even on the low-boost install. it will run OK on the standard ecu, but it will be running very lean, drink fuel, and slowly kill the engines innards.

management options are:

Megasquirt (this involves making up a custom loom) Unichip with boost module dreamscience Omex and many more...

also it is better to fit a wideband lamda sensor with innovate LC-1 system, and an air-fuel ratio guage.

BOOST CONTROL:

you can use the cheap age old method of a bleed valve with boost guage, or there is dozens of different types of electronic boost controllers on the market to link up to your wastegate with a solenoid. some incorporate turbo timers, datalogging and all sorts.

Exhaust system:

better to have the 2.5" diameter exhaust system from a v6 or from powerflow or blueflame. the standard cat wont like the extra power, so its better to not have one or run a sports cat.

INDUCTION:

not much room for induction pipe (especially on cable clutch mondeos), on mine it has a modified rover pipe with a cone filter

CLUTCH:

the standard 2.0 clutch will start slipping at around 200-210bhp. even at 10psi you will find some clutch slip at higher revs, especially in 4th gear. on a blacktop there is several types of uprated clutch available off the shelf, on the silvertop cable clutch the only place i could find was techniclutch who made me a 4-paddle organic one costing £270 (which was mid 2008)

the 1.8TD clutch will also fit, and can take around 300bhp from a zetec turbo but it wont last very long (one lasted 8k miles in mine)

BREATHERS:

you must link up breather pipes to the block and cam cover, linked to an oil catch can.

HIGHER BOOST OPTION:

to run more than 10psi you need to lower the compression ratio of the engine.

the budget method of doing this is using a decompression plate between the head and the block. mine uses this method with uprated head gasets and has been running 19psi boost with a T28 turbo for 2-3 years now with no probs. mine also has ceramic coated mahle pistons, and ARP conrod bolts. decent mapping and decent breather system should make it safe to do it with a decomp plate. a company in USA tested a focus zetec turbo to 375whp on the standard bottom end.

the ideal method is using forged low comp pistons with steel conrods and ARP rod bolts

another option is calibra turbo pistons but they need some work to fit the zetec block.

Eagle (a USA manufacturer) sell the forged pistons and rods for about half the price of what you would pay over here.

CAMS:

the standard 2.0 cams work well with forced induction. otherwise piper, area 6 and some USA companies make turbo cams. these are only really needed if you want over 350bhp.

TURBO's:

mine is using a hybrid T28 from a Nissan Pulsar GTiR. i'm finding it is an excellent turbo with very little lag.

T3 or T34 would also be very good, T4's are more for 400-500bhp applications (laggy, but party time once its on boost)

a dump valve will help the turbo spool up quicker and will help keep the turbo lasting longer.

DIFF:

the standard diff in the MTX75 gearbox will periodically explode when running 250-275bhp. you can replace with quaiffe or ford racing torsen diff. you will also notice that at that power level you really need the LSD on a fwd

FUELLING:

the standard fuel pump and fuel pressure regulator will be reaching their limits at 250-275bhp so it is better to fit uprated items. on mine its using an uprated warlbro escort cosworth fuel pump.

OTHER BITS:

above 250-275bhp the mondeo will also eat alot of tyres, wishbone bushes and engine mounts. so replacing mounts and bushes with polyurethane items will solve this.

to help get all the power down on a higher boost install, you really need to be polybushing all the suspension, get firmer shorter shocks, lowering springs (or coilovers), front & rear strut braces, uprated drop links, and bigger wider wheels with sticky tyres. and obviously fit some bigger brakes.

it is also advisable to fit a detonation alert system, and have the car mapped to run on super unleaded.

some porting/smoothing of the cylinder head will make everything work better.

engine bay temps will be an issue, consider fitting some bonnet vents.

if the car you intend to turbo is old and/or has high miles, consider getting a newer engine to start off with. also seriously consider replacing many of the oil and water pipes (and their hose clips) around the engine, they will start to split/leak once the engine is under boost.

also as a matter of course change the cambelt and water pump, fuel filter, and obviously the oil & coolant.

another point is the standard plastic header tank is liable to cracking under higher boost levels, so get an alloy tank to avoid overheating issues. a thicker alloy rad will help here also.

i will add more to this as time goes on.