Corsa C c20let vs z20let

[Danb1987]

Probably the wrong place but does anyone know what the differences are between these engines in said car?? I'm picking my corsa up tomorrow and taking it for a c20let conversion!! And iv not really seen many??

[Southie]

The C20LET is based on the old redtop C20XE - the Z20LET is based on the X20XEV unit found in the 2L MK4 Astra - balancer shafts probably one of the more obvious differences although you are correct the Z is newer and compliant with later emission regs


Z20 LET









http://www.zlet.co.uk/images/zletengine.jpg

The 2.0 litre ECOTEC 16-valve turbocharged engine delivers peak power of 147kW @ 5600rpm. The torque curve rises steeply from almost any idle speed and reaches its peak of 250Nm at 1950rpm (PULP) and a constant boost pressure of 0.85 bar, or 12.33 psi. The torque curve remains virtually flat with maximum pulling power available up to 5600rpm.

The electronic engine management system makes additional power available for acceleration at full load, allowing the engine cut-off speed of 6400rpm to be exceeded by 400rpm for short periods to ensure ideal transitions between gears.

The engine is a model of efficient packaging; all the components specific to the turbocharger have been accommodated without modification to the body or engine compartment.

The K04 Turbocharger unit incorporates friction-type bearings. The minimum/maximum revolution speeds are 5000rpm and 164,000rpm respectively.

In the integral turbocharger system, the exhaust manifold and turbine casing are combined into a single module with other components.

Advantages include compact dimensions and low weight; the casing weighs 4.3kg and the entire module weighs 7.1kg, which is about 1.3kg heavier than the cast manifold of the comparable naturally aspirated engine. Other advantages are its uniform wall thickness, which allows the engine to react quickly to temperature changes in the exhaust system, the reduced number of components and the elimination of a seal between the turbocharger casing and the turbine.

The basic engine dimensions are notable for a precisely square bore/stroke ratio of 86.0/86.0mm, cylinder spacing of 93mm and a compression ratio of 8.8:1.

The splash-lubricated pistons are manufactured from an aluminium/silicon alloy to ensure rapid heat dissipation and high mechanical strength.

Piston design also takes acoustic optimisation into account. The centre lines of the floating piston rings, for example, are offset by 0.8mm towards the pressure side of the piston. Two counter-rotating balance shafts ensure smooth, quiet operation. The four valves per cylinder have sodium-cooled exhaust valves and are driven directly via hydraulic bucket tappets from two camshafts with sporty cam profiles.

The turbocharger is connected to the engine’s lubricating and cooling circuits by separate feed lines. An oil cooler ensures thermal stability in the engine and its auxiliaries. A charge-air intercooler increases the amount of air entering the engine, promoting efficiency and torque development. A latest-generation computer system is responsible for overall engine management. Among other things, it controls the boost pressure using integrated relief and rotary valves.

The electronic ‘drive by wire’ accelerator, hot-film air mass meter, sequential fuel injection, individual-coil direct ignition and cylinder-selective knock control are all co-ordinated by the electronic management system.

On the road, the integrated turbocharger is notable for its spontaneous response to accelerator movements and its flexibility, even at low engine speeds. Short flow paths between the engine exhaust duct and the turbine and the low inertia of the compact turbocharger promote plenty of low-end torque.

Pollutants are substantially reduced by a double catalytic converter system comprised of a primary converter close to the engine, which comes on line quickly, and a large-volume main converter.

To achieve the maximum conversion rate, metal instead of ceramic material is used for the substrate that supports the catalytic precious metal coating. Two oxygen sensors monitor the combustion process: one is upstream of the primary converter and controls the composition of the fuel/air mixture, while the second, downstream of the main converter, is used for diagnostic purposes. This advanced concept allows Astra Turbo models to meet the Euro 4 emissions standard that comes into force in 2005 in Europe.

Engine validation testing involved a number of special test programs, including extreme altitude, winter and summer tests. As an example, in thermal shock tests, engine coolant was chilled to minus 25° C and within a few seconds the engine was subjected to full load.

Additional Australian testing of prototype vehicles and engines included powertrain suitability of the Z20LET and correct operation of engine management systems, calibrations and transmissions in hot ambient temperatures.

Existing hot test data, including Opel test results, were analysed to determine regional audit requirements.

Resulting engine calibration testing included purge operation, knock control, hot start and hot fuel handling and hot vehicle performance.

Manual transmission operation, oil temperature testing, and HVAC performance and cooling validation was carried out. In addition, vehicle durability testing confirmed the vehicles met Australian requirements

[Edd]

IMO a z20let is a ball of crap

VERY weak engine and components imo, afm, turbo, boost solinoids will all fail with ease.

c20let were hand built afaik, z let's are not.

I for one will not own another, my low millage Astra mk4 gsi was nothing but grief and i know im not the only person who's had lots of trouble with them.

[Danb1987]

That's abit more reassuring lol hopefully the c20let won't let me down!! How light can you make corsa's I know obviously not aslight as novas!

[Rich]

z20let - got a mk4 gsi myself. Its a newer, better engine. ecu is mappable as standard

Or z20leh with zlet manifolds and managment

[dj_wudgey]

as stated i know people to have problems with these id rather go c20 let if i had the choice ff either!!

[Kev Turbo]

z20let - got a mk4 gsi myself. Its a newer, better engine. ecu is mappable as standard

Or z20leh with zlet manifolds and managment

As above :)

Bit silly taking your car for a conversion which you dont really seem to know a lot about.

Zlet all the way for me - On phase 4 they are 300bhp ish.

More than ample power for a corsa and very reliable

Yes you will have to replace the turbo from time to time but not expensive

The zlet is very much suited to the corsa.

Just my 2p worth xxx

[Will F]

As said - the C20let is much more of a ball ache in the Corsa C - need about 30 ECUs, convert the pedal to cable, and an aftermarket coolent gauge iirc.

The Z20 bolts up, and if the car was a 1.2 16v you can even use the loom and ECU (re-flashed)

[Sloth]

As said - the C20let is much more of a ball ache in the Corsa C - need about 30 ECUs, convert the pedal to cable, and an aftermarket coolent gauge iirc.

The Z20 bolts up, and if the car was a 1.2 16v you can even use the loom and ECU (re-flashed)

/\ this. tbh anyone who puts a clet into a c is just lazy, when infact it makes more work for you. the z let is an excellent engine, yes the earlier ones are a bit touchey but the later ones are more refined.

[Danb1987]

The reason I'm putting a c20let in is because it's sat in my rotten nova! And u got the c dirt cheap! It's already at the conversion place so it made sense!! That's all lol

[Sloth]

sell the c let and buy a z let, prices are the same atm.

[Kev Turbo]

The reason I'm putting a c20let in is because it's sat in my rotten nova! And u got the c dirt cheap! It's already at the conversion place so it made sense!! That's all lol

Dont see the sence in that theory at all !Lol