View source for 2g Astron II

[[Image:2g_head.jpg|200px|right|thumb|Second Generation Astron II combustion chambers]]
[[Image:2g_rollers.jpg|200px|right|thumb|Rocker gear on the Second Generation Astron II]]
[[Image:2g_piston.jpg|200px|right|thumb|Second Generation Astron II dished pistons]]
The '''second generation [[Astron II]]''' was fitted to fuel-injected TR and TS models.

The revised Astron II included "kidney shaped" combustion chambers in the cylinder head, roller rockers, dished top pistons and the self-adjusting [[balance shaft]] chain adjusting mechanism fitted to late model Astron IIs.

The quickest way to identify the second generation Astron II from the original is to look for a knock sensor under the injection plant. First generation Astron IIs do not even have a hole for it. Other methods are by it's engine number (prefixed by W531, W532) or by the casting number on the head. Second generation heads are marked "M9".

As a result of these modifications the compression ratio raised to 9.2:1 and power rose to 98kW @ 4750 rpm (103 kW if ran on premium unleaded thanks to the knock sensor included as part of the engine management system). Torque also rose to 212Nm @ 3750 rpm.
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==Technical Specifications==
{|cellpadding="3" align="left"
|'''Type'''
|In line 4 cylinder overhead cam with counter balance shafts. Transversely mounted
|-
|'''Displacement'''
|2555cc (2.6 litres)
|-
|'''Bore'''
|91.1mm
|-
|'''Stroke'''
|98mm
|-
|'''Maximum oversize'''
|1.00mm
|-
|'''Compression Ratio'''
|9.2:1
|-
|'''Firing Order'''
|1,3,4,2
|-
|'''Power Output (EFI)'''
|98 kW @ 4750 rpm (103kW when running PULP), 212 Nm @ 3750 rpm
|-
|colspan="2"|'''HEAD SPECIFICATIONS'''
|-
|'''Type'''
|Alluminum Alloy with hemispherical combustion chambers and crossflow design
|-
|'''Inlet Valve Diameter'''
|46.00mm
|-
|'''Exhaust Valve Diameter'''
|38.00mm
|-
|'''Valve Face Angle'''
|45 &ordm;
|-
|'''Valve Clearance'''
|Maintained by hydraulic lash adjusters
|-
|colspan="2"|'''CAMSHAFT SPECIFICATIONS'''
|-
|'''Inlet Opens'''
|25&ordm; BTDC
|-
|'''Inlet Closes'''
|61&ordm; ABDC
|-
|'''Inlet Duration'''
|266&ordm;
|-
|'''Exhaust Opens'''
|66&ordm; BBDC
|-
|'''Exhaust Closes'''
|20&ordm; ABDC
|-
|'''Exhaust Duration'''
|266&ordm;
|-
|'''Overlap'''
|45&ordm;
|-
|'''Inlet Cam Lobe Height'''
|42.50mm
|-
|'''Exhaust Cam Lobe Height'''
|42.56mm
|-
|'''Nominal Cam Lift'''
|10.50mm
|}
|-
|{{Mitsubishi Engines}}
|}

[[Category:Second Generation Magna/Verada]]
[[Category:Astron Engines]]