Voxwagen
Eurospec Head
and
G-grind Cam

The design of Volkswagen's 8V head is often seen as an impediment to high performance. Few claim to be making more than 120 HP with a normally aspirated engine that has not had porting and polishing done to the head.

However, porting and polishing a cylinder head is a hands on art. Perhaps black magic. It would seem to be difficult to ensure the outcome of this work. An alternative would be to find an aftermarket head. One manufactured with better flow characteristics.

Eurospec's philosophy struck a chord. Their investment in time and money to produce their head seemed substantial.

From their site-

To avoid the expensive and unpredictable nature of hand ported cylinder heads, Eurospec chose to redesign the Volkswagen 026 based four cylinder head. Our cylinder head ports are cast with a shape that we have determined to maximize flow. The starting point is a rough cast Eurospec cylinder head. This is then machined and finished in-house using CNC machining equipment. Final hand porting cleans the casting, ridding it of roughness, without imprecisely removing excess material. Prior to dispatch, every head is inspected to ensure it meets specifications.

Favourable reviews and elapsed times of people using their head were impressive.

Note the extra cam guide on the solid lifter head.



Stock port sizes
Inlet 30 mm x 33 mm
Exhaust 25 mm x 32 mm

Eurospec port sizes
Inlet 34 mm x 38 mm
Exhaust 30 mm x 37 mm

The choice of valves on the Fox was one of the ways its economy image was ensured.
The small 38 mm intake valves limit the engines ability to breathe.

This head uses 40 mm Intake and 33 mm Exhaust.
The same size valve as in the VW big valve head used on the GTi.

The standard hydraulic cam shaft is the A casting.
It has a duration of 210.5 Intake, 209.5 Exhaust @0.50" with a lift of .393".
G castings have also turned up in Fox motors.
The G casting has a duration of 214 @0.50" with a lift of .400".

The Solid lifter G-Grind cam has a duration of 230 Intake, 228 Exhaust @0.50" with a lift of .423".

Here it is nestled in its new home.

Sight
Externally there is very little difference between the stock hydro head and the solid lifter head. It is cleaner. The casting may be slightly cleaner (a greater degree of finish). The air shrouds around the injectors are gone. The fresh coat of paint on the intake manifold is probably the most noticeable change. But those who know, do a double take when they see "Eurospec" cast in the side of the head.

Sound
The tickety tickety tickety of the lifters on a cold engine is musical. It is a bit of nostalgia. Bringing back memories of the old Rabbit and at the same time conjuring delusional images of a true sports car. Once under way the noise is no more obtrusive than before. The quiet clatter lost in other road noises... especially the exhaust note which has changed in timbre to a richer, fuller, deeper sound.
The idle with the some what conservative G grind cam is  smooth. No objectionable lumpiness.

Drive
It was not without some trepidation that a head with such large ports was put on an engine of only 1781 cc. There was a concern that all bottom end torque would be lost.  Would the motor need to be revved to 4000 RPM before there was enough power to move the car? This was not the case. There is no drivability issue. There is plenty of power down low.

The engine revs freely through 6000 RPM. The old small valve head seemed to be breathless at about 5500 RPM even though this was near where the engine was producing it greatest horse power. The revs climb so willingly that hitting the rev limiter is effortless. 

The engine has more power. It feels like it is pulling all the way to red line. The power band before seemed narrow and combined with the relatively long gears in the transmission demanded the car be driven aggressively. With more power available over a wider range and the engine's new-found willingness to rev, this need is gone. The match with the transmission just got better.

The engine never feels like it is labouring. Climbing hills, on the highway or launching from a light, the motor is now going about its job with little fuss or bother. Hills that used to require down shifting can now be tackled without. It seems stronger. It has improved "lug-ability". In a strange way the car feels more luxurious and less like an econo-box.

This seems to have been a fine step in the evolution of this Fox and should ensure greater benefit from future modifications, as who know how long the displacement will remain 1.8l or the aspiration normal....

Though I am greatly enjoying this set up there are improvements planned when the head has to come off the next time. The valves could have a radius cut or 5 angle valve job. The stems could be undercut. The valves could be unshrouded. All of which should move even more air though the engine.