Garrett Upgrades 2.0 Turbo Z20LEx

V Band Cast Manifold Z20LEx

For significant gains in performance above the OE Z20LEH K04 exhaust manifold, this new cast manifold offers an ideal solution. Developed in conjunction with our German Tuning partner Klasen Motors, this manifold offers the OE durability of a cast manifold, unlike stainless steel tubular manifolds which are prone to cracking, has a high quality finish, is manufactured from high quality materials and has been flow tested to 600bhp, although Stephan has produced a 689PS conversion with the manifold. Features a TiAL V-Band mounting flange for any suitable turbocharger plus external wastegate, again on a TiAL V-Band flange. This can be capped if an internal wastegate option is required. The V-Band flange provides better security of the turbocharger to the manifold, and is less prone to backing off unlike traditional 4 bolt garrett flanges, and also allows for the retention of the air conditioning system.
D5S material with high nickel content Turbocharger and waste gate have V-band flanges TiAL 44mm external wastegate (water cooling possible) TiAL exhaust housing with a V-band flange	Example Z20LEx GT V Band Kit
Prices: V Band Manifold £599.00 TiAL MVR44 External Wastegate £339.00 Self Install Kit GT28RS - up to 350bhp £2495.00 Self Install Kit GT2871R - up to 400bhp £2595.00 Self Install Kit GT3076 - up to 480bhp £2725.00 Will also accept the new Garrett GTx range of turbos. Self Install Kit GTx2876R - £2895 Self Install Kit GTx3071R - £2995 Self Install Kit GTx3076R - up to 525bhp (99RON Fuel) £3145.00
Note: GTx range of turbos feature anti-surge as standard. Locktabs are available for an additional £75.00 Full Garret Build and Install with V Band Cast Manifold is available in our workshop All parts from the V Band Kits are available separately.

Astra H VXR V Band Manifold Garrett GTx3076R Conversion - 559bhp

Duration: 1:50

V Band Cast Manifold, Garrett GTx3076R turbo 0.86 A/R, TiAL V-Band Flange, External Wastegate, Full Engine Rebuild, Steel Rods, High Flow 728cc Injectors, External Swirl Pot, High Pressure Pierburg Pump, Methanol Injection with 2 Injectors, 90mm Air Flow Meter, AEM Dry Flow Filter, Enlarged Plenum, High Flow Courtenay Klasen Inlet Manifold, Uprated Courtenay Klasen Inlet and Exhaust Cams, Courtenay Sport VXRacing Intercooler, 3" Full Exhaust System, bespoke mapping of the OE Bosch 7.6.3 ECU.

Astra H VXR V Band Manifold Garrett GT3076 Conversion - 479bhp

V Band Cast Manifold, Garrett GT3076 turbo, TiAL V-Band Flange, External Wastegate, Standard Z20LEH pistons (which are good for 500bhp), steel rods, High Flow Injectors, 90mm air flow meter, high flow enlarged plenum, high flow Courtenay Klasen Inlet Manifold, uprated inlet and exhaust cams, Courtenay Sport VXRacing intercooler, 3" full exhaust system, bespoke mapping of the OE Bosch 7.6.3 ECU.
	Video - Duration: 1:08

VX220 Turbo V Band Manifold Garrett Conversions - 398bhp and 689bhp!!

398bhp VX220 Turbo V Band Manifold, TiAL External Wastegate, Garrett GT2871R, Full Engine Rebuild, 3" Exhaust System, Chargecooler System - build for Road and Track use.

689bhp Speedster Turbo V Band Manifold, Garrett GT35, Methanol Injection, Solid Lifters - built for the drag strip.

 High Flow Inlet Manifold

Prototype V1

Plastic Prototype V2

Plastic Prototype V3

CAD Drawing - V4

Prototype Version 1 was a simple design with its squashed plenum it produced good high end bhp however more work was needed with the  plenum for more even air distribution.

Prototype Version 2 featured a dual plenum design this produced good air distribution and good bhp numbers due to is short inlet tract it was good for power to 8000+ rpm, however when tried with the plastic prototype V2 this power was at the cost of low end torque and mid range power. So was considered too extreme for most applications.

Prototype Version 3 was the beginnings of the manifold we ended up with. The inlet tracts were made longer to keep a good torque spread, whilst the pre-resonance chamber made larger and improved in shape for enhanced air flow. A costly plastic prototype was again made for testing.

This proved invaluable as the bottom end power and torque was vastly improved, however we felt that the top end power could be further enhanced with larger ports. This proved the best balance between low end torque and power and high end power, showing improved power / boost ratio at 455 bhp
(we did not dare run it at higher boost than this as it was making some nasty noises due it being made from plastic, whilst others in the workshop feared 1st degree plastic lacerations!!)

Version 4 was the final version with only subtle mods being made to the pre-resonance to port transition whilst externally some hardware mounting points altered.

The inlet manifold has so far been tested to 520 bhp. >>>

Gains on a car fitted with a K04-Race turbo. >>>

We have also tried the manifold on an engine equipped with a VXR K04 turbo whilst not expecting any huge gains with an engine already running 290 to 300 bhp we were pleased to see the inlet manifold fitted (red trace). Once mapped to suit the inlet manifold showed power gains from 5,700 rpm, with gains of 10 bhp at 6,000rpm, 23 bhp at 6,500 rpm and 29bhp at 7,000 rpm. In the past this has only been achieved by fitting cams the result of this can lead to an unwanted lumpy idle, whilst fitting an inlet manifold and leaving the standard cam profile leaves the idle smooth as standard. (Figures shown on the graph are at the wheel figures)

Images show High Flow Manifold fitted up to an engine with our Enlarged High Flow Plenum. This manifold is not just for big power Garrett builds. It will produce excellent gains on a Stage 3 and 4 Astra/Zafira VXR, Astra/Zafira GSi and VX220 Turbo fitted with K04 and K06 turbochargers. Our High Flow Inlet Manifold has been designed for ALL Z20LEx petrol turbo engines. Designed to remove the restriction in the original inlet manifold that restricts air flow into the engine. This manifold will allow the engine to breathe fully, and has been designed to increase power but not at the expense of mid range power and torque (for example, a shorter inlet manifold will give good power at extremely high end rpm i.e. 8,500 rpm but will lose mid range torque). Ideal for fast road and track use. Gains can be seen on a Stage 3 300bhp Astra VXR set up, Stage 4 Astra VXR with K06 Hybrid Turbo with no loss in mid range torque and on a full Garrett build running a GT28/30/35 turbo unit, allowing the engine to continue to produce power well above 7,000 rpm. From our experience we have found this to be a much more worthwhile upgrade to the Z20LEx engine than fitting a cams as an upgrade, as not only are the results better but there is no unwanted lumpy idle associated with high lift cams as this inlet manifold can be fitted whilst retaining the standard cams. High Flow Inlet Manifold - £598.00 £500.00 High Flow Inlet Manifold and Enlarged High Flow Plenum - £660.00 £562.00 The power and torque graphs below show before and after graphs of a selection of vehicles that have had conversions both with and without our high flow inlet manifold and the benefits can be clearly seen.

Stage 3 Astra VXR Before Without and After With Inlet Manifold

Stage 4 Astra VXR K06 Turbo Before Without and After With Inlet Manifold

Astra Z20LEx GT28 Build Before Without and After With Inlet Manifold

A selection of Garrett installs that we have done......

V Band Cast Manifold	V Band Cast Manifold	V Band Cast Manifold
Tubular Manifold GT30	Tubular Manifold GT28	Tubular Manifold GT28
GT30 on Cast Manifold with Aircon	TT35 with Cast Manifold	TT35 with Cast Manifold

Engine Strengthening (Z20LEx engines) when upgrading.......

What else is required?.......

High Lift Cams for Garrett Builds

Developed with our tuning partner Klasen Motors, after substantial testing, these high lift cams been specifically profiled to suit high power Garrett turbo builds sustaining power at the upper end of the rev range, ideally suited to large turbochargers capable of making high boost levels above 6,500 rpm. They give a wide rev range up to 7500rpm and constant maximum power from 5,500 - 7,500 rpm where with the standard cams the maximum power drops at 5500rpm. Specially developed for turbocharged engines the exhaust cam gives good turbo response and less exhaust gas in the cylinder head reducing back pressure.

These cams are machined from blanks on a modern CNC-camgrinding machine and have a lift of 10.6mm. They can be fitted on standard cam settings, (you only need vernier pullies if the cylinder head has been machined.) With big Garrett applications we measured 70bhp more at 7000rpm compared to standard cams. £569 per pair

Thermal Inlet Gasket - Z20LEx

Thermal Inlet Gasket (TIG) for Z20LEx engines - designed to reduce heat-soak from the cylinder head to the inlet manifold. Ideal for use with any engine, but especially big power builds. Heat management is an area that is often ignored during engine modification. The Thermal Inlet Gasket will help prevent heat from conducting from the cylinder head casting into the inlet manifold, significantly reducing heat soak. In theory, because of the cooler and denser inlet charge, a small and immediate power increase should be evident (if you can run a little more ignition timing before pre-ignition occurs then power should rise), but their main strength will be in helping to keep temperatures under control during and after prolonged engine use.

This 4mm thick high performance composite gasket, designed for optimal heat insulation, is available for Z20LEx engines is paper coated on both sides to aid sealing. Note: The TIG is paper coated on each side and designed to seal between two flat surfaces. If there is any doubt about the quality of either surface a thin bead of sealant should be used on both sides (not recommended unless absolutely necessary). If the paper gaskets are damaged during strip down/rebuild, they can be replaced with a pair of OE gaskets. Gasket £45.00

90mm Air Flow Meter Housing

90mm Air Flow Meter Housing for 400 - 650bhp conversions. Requires a meter head from an 80mm Bosch (Astra VXR) Air Flow Meter. Housing £90.00 90mm Air Flow Meter Complete £228.00

90mm AFM Housing

90mm and 80mm AFM

NGK Spark Plugs

Cooler running NGK spark plugs for big horsepower turbo applications 7EIX - £35.80 Set of 4 8EIX - £35.80 Set of 4

Bosch Map Sensors

We can supply a range of map sensors with a wider calibration scale to suit higher boost applications including 3 Bar, 3.5 Bar and 4 Bar. OE 2.5 bar are sensors are also available. From £50.00 - £99.00

630cc High Flow Injectors

630cc at 3 bar. High Flow Fuel Injectors for high power engines up to 450bhp - 500bhp. £395 Set of 4

Uprated Fuel Pump

For Astra G, Zafira A, Astra G and Zafira B models including VXR running big horsepower and high boost levels, fuelling is critical. This replacement uprated fuel pump is ideal to take over from the original 'OE' fuel pump to maintain good fuel flow where the OE pump begins to struggle. This pump is capable of running at up to 2.9 litres per minute, which is good for cars running up to 350 bhp. Fits in place of original pump, with modification to the OE housing £102.30 Convoluted Flexi Fuel Hose also available

Engine Rebuilding and Components. A separate page with details of our engine rebuilding services and components; Forged Pistons, Steel Rods, Balancer Shaft Deletion Kit.

Genuine Z20LEH Forged Pistons and Steel Rods Kit

Wossner Forged Pistons

Wossner Forged Pistons and Steel Rods Kit

Uprated Lightweight Steel Rods and Rod Bolts Kit

Balancer Shaft Removal Kit

Uprated Multi Layer High Performance Metal Head Gaskets

We have multi layer uprated metal head gaskets available for all high power builds. High Performance 4 Layer Gasket - 1.3mm when compressed. CR: 8.4:1 with Cosworth Pistons Ultra Performance 5 Layer Gasket - 1.9mm when compressed. CR: 8.0:1 with Cosworth Pistons Price - £139.95 HP 1.3mm Gasket   UP 1.9mm Gasket

Engine Rebuild Components - Gasket Sets, Bearings, Head Bolts

Not only can we supply pistons and rods but for anyone carrying out their own engine build we can supply head gaskets, top and bottom gasket sets, big end bearings, main bearings, oil pumps, water pumps, cambelt kits and auxiliary drive belts. In fact everything you will need. Most parts are available for online purchase from our shop. For a list of components click on the button >>>>>>

Cast Manifold for Garrett Turbo

Cast manifold for Z20LEx applications fitted with a Garret 4 Bolt flange T25, T28, T30. Ideal for Garrett conversions up to 400bhp and a good alternative to a tubular manifold. A cast item is generally stronger and more durable plus it will not heat soak the engine bay in quite the same way. It also retains a degree of 'OE' look in the engine bay. Suitable for Garrett turbo with 4 bolt flange for all Z20LEx engines. It is recommended that for durability and reliability additional strengthening of pistons and rods is carried out to non LEH engines, while for LEH engines steel rods are recommended, depending on required power and torque figures. Cast Manifold - £510.00

331bhp - 361 lb ft

336 bhp - 358 lb ft

354 bhp - 348 lb ft

373 bhp - 339 lb ft

Fitted Conversion

Fitted Conversion

Tubular Manifold for GT28/30 and Downpipe - Z20LEx turbo engines.

Suitable for Z20LET/Z20LEL/Z20LER/Z20LEH engines with the required internal work. This kit consists of an equal length tubular manifold, 3" downpipe suitable for the GT28 turbo unit, turbo inlet pipe and breather pipe. We can also supply a GT28 turbo charger built to a specification to suit individual power requirements. Tubular Manifold - £795 Downpipe, Inlet Pipe, Breather Pipe - £765.00 Full Kit - £1560 GT28 Turbo built to individual specification from £1175.00 GT30 Turbo built to individual specification from £1225.00

Fitted Tubular Manifold

Manifold and GT28

Astra GSi Turbo Garrett Build GT2871 - Graph and Video

Courtenay Sport Stage 5 Tuned Astra GSi Turbo. Garrett GT2871RS turbo (built to our own spec) with Courtenay Sport equal length tubular manifold, fully rebuilt engine, forged pistons, steel rods, lightened and balanced, under piston cooling installed, High Flow Injectors (550cc), 80mm air flow meter, high flow enlarged plenum, high flow Courtenay Klasen Inlet Manifold, uprated inlet and exhaust cams, modified head, Astra VXR (Courtenay VXRPC) VXRacing intercooler, 3" bespoke exhaust system with sports cat and custom mapping of the original Bosch 1.5.5 ECU (standalone management not required!!).

Power Graph

Duration: 2.21

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