Reinforced exhaust valves Peugeot 309 GTI 16 405 Mi16 XU9J4

Peugeot engines covered

The XU9J4 is the PSA 1.9 litre, 16-valve four of the Peugeot 309 GTI 16 and 405 Mi16, offered as the XU9J4Z on the four-wheel-drive 405.

Its 8 exhaust valves have a 7 mm stem; on these engines, often pushed in rallying or on track, they face high revs and the heat of the burnt gases.

CATCAMS reinforced exhaust valves

Naturally aspirated, the metal of the exhaust head reaches 760 to 870 °C. The seat removes about 75 % of it and the guide about 20 %. An EV8 family steel gives the order of magnitude: 550 MPa at 600 °C, and only 300 MPa at 800 °C; beyond that, the head fatigues, distorts and no longer seals properly.

CATCAMS offers the 9249013M for this engine, supplied here as a set of 8: 29.5 mm head, 7 mm stem and 105.7 mm length.

Exhaust valve technical specifications

The 9249013M is the only exhaust valve in the range for the XU9J4.

Valve fitting

Before refitting the springs, check that the collets suit the groove of the valves.

Check the clearance of the 7 mm stem in the existing guides before fitting.

The exhaust seats are reground to suit the new valve during the cylinder head rebuild.

Technical guide

Our brand

CATCAMS, a European camshaft and valvetrain specialist, offers the 9249013M for the XU9J4, supplied here as a set of 8.

How to choose

Only one version is offered for this engine:

When reinforced valves become necessary

• More aggressive camshafts
• Raised rev limit
• Rally, hillclimb or track
• Cylinder head rebuild with worn exhaust valves

Vehicle compatibility

OEM part number (exhaust valve):

Don't forget the inlet valves

An XU9J4 cylinder head on the bench is the right time to replace the inlet valves and the valve stem seals too.