1975 LA Lancer Buildup - Engine
The engine being fitted to my Lancer is from a 1971-72 Galant GTO-MR. It was the first production twin cam engine from Mitsubishi and only 850 were built, all destined for the Japanese domestic market. Due to the rairty of the engine and the fact that it was only available from Japan, tracking down information and verifying it to be correct can be very difficult.
I have managed to obtain a copy of the factory workshop manual for Galant GTO, which includes the GTO-MR, so I have the basic details of the engine.
The factory specifications are below (some of the specs have been changed in my engine):
| Engine Transmission Model | 4G32-1-90A |
| Number and arrangements of Cylinders | 4 in-line longitudinal |
| Method of cooling | Water |
| Operation cycles | 4 |
| Combustion chamber type | semi-spherical |
| Valve Arrangement | Double overhead valve type |
| Bore and Stroke | 76.9 x 86 |
| Total Displacement | 1597 |
| Compression ratio | 9.5:1 |
| Compression pressure | 125psi @ 250rpm |
| Maximum output | 125ps @ 6800rpm |
| Overall dimensions | 616 x 615 x 666 mm (L x H x W) |
| Engine weight with accessories | 142 kg |
| Piston type | solid |
| No. of piston rings | 2 (compression) 1 (oil rings) |
| Valve timing | Intake opens - B.T.D.C. 32º |
| Valve timing | Intake closes - A.B.D.C. 52º |
| Valve timing | Exhaust opens - B.B.D.C. 52º |
| Valve timing | Exhaust closes - A.T.D.C. 32º |
| Valve Clearance | Intake - 0.30 |
| Valve Clearance | Exhaust - 0.30 |
| No-load speed rpm | 800 to 850 |
| Starting method | Starting motor type |
| Blow-by gas removing system | Closed |
| Ignition method | Battery ignition |
| Ignition timing | 18º B.T.D.C. @ 800 rpm |
| Firing order | 1-3-4-2 |
| Ignition coil type | TB63 |
| Distributor type | TVG- 4CR |
| Performance of spark advancer | Centrifugal type - 0º/500rpm, 16º/2000rpm |
| Performance of spark advancer | Vacuum type - 0º/40mmHg, 20º/160mmHg |
| Spark plugs | Type - BP6ES (NGK) |
| Spark plugs | Thread - 14mm |
| Spark plugs |
Plug Gap - 0.7 to 0.8mm |
| Carburettor | Type - Solex type with idle limiter |
| Carburettor | Model - 40PHH |
| Carburettor | Gas valve diameter - 40mm |
| Carburettor | Venturi diameter - 32mm |
| Carburettor | Choke type - Manual choke type |
| Fuel pump | Electromagnetic type |
| Oil pump type | Geared pump type |
| Oil capacity | 5.0 litre |
Here are some photos of the engine (click on each photo for a larger image to open in a new window)