Engine buildup

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Your Nissan A engine is built for spritely power but with maximum longevity. If you want to trade off a built of reliability and wear-time, you can increase the horsepower significantly.

The following applies to all Nissan As: A10, A12, A13, A14, A15 and A12A.

Baseline Tuning

Tuning your car to factory specification -- without buying a hotrod parts -- can double the horsepower of your car. Even when relatively new, cars could be far out of tune.

See SUPERTUNE -- Datsun 1200].

Be sure to start here. Adding aftermarket "performance" parts won't help an engine that has basic tuning flaws in the first place.

First Upgrade

The biggest change you can make is to add a larger carburetor.

• It won't make the engine run better below 4,000 rpm
• From 4,000 = 6,000 RPM will improve significantly

Adding a carburetor is relatively easy. The most popular swap is the Weber 32/36 DGV family. See Choosing a Carburetor.

Of course at higher RPMs your engine will wear out faster. It is a trade-off you need to decide on.

Engine Swap

Before you go farther, decide whether you should swap in a larger engine. For example, going from an A12 to an A15 may cost around $500 but will equal about $2000 worth of "buildup" for an A12.

A15 with larger carb: 95 gross hp. Cost: $ A12 build lots of work: 95 gross hp. Cost $$$ And the A15 will still have an acceleration advantage, having more average horsepower (25% more power at low RPMs).

Stage One Buildup

Stage one is all about bolt-on induction improvements. This is relatively easy -- but doesn't involve removing the engine.

$

• Larger carburetor, e.g. Weber 32/36 (see Choosing a Carburetor)
• Exhaust headers (extractors)
• 1.75 inch diamter exhaust (entire exhaust, including muffler)

On an A12 engine, this might make, what? 75hp? (compared to 69hp stock). This is measured on an engine dyno (Factory specs are *not* measured by rear-wheel-horsepower -- see Performance).

Or: $$

• Sidedraft inlet manifold
• Twin sidedraft carburetors (see Choosing a Carburetor)
• Exhaust headers (extractors)
• 2.00 inch diamter exhaust (entire exhaust, including muffler)

On an A12 engine, this might make, what? 80hp?

Stage Two

Stage Two requires engine work on the inlet and exhaust side. It builds on Stage 1 by adding:

$$$

• Performance Camshaft
• Cylinder head work:
  • Port and polish and larger valves, or
  • Oval-port head swap

On an A12 engine, this might make, what? 100hp?

Alternatively, adding a turbocharger or supercharger will make equivalent maxium horsepower but with more low-speed horsepower. See Forced Induction

Stage Three

Stage Two is a high-dollar option that includes new pistons. It builds on Stage 1 by adding:

$$$$

• Flattop pistons (for A12, use Datsun 1000 coupe pistons from KB10 model), or
• Forged dome-top high compression piston

High Compression pistons will add 3% or more horsepower, but you will need to buy premium fuel.