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Revision as of 04:51, 27 November 2006

What's the Best Engine?

Engine stuff you need to know

Best engine -- the A12?

There is no "best" engine, unless popularity counts for anything. Millions were produced with the A12 engine, making it the most successful. Plus, the 1971-1973 A12 simply fits into the 1200 engine compartment by design of Nissan factory experts.

A special hi-po version of the A12 is the A12GX Engine. These came in Japanese-built GX 1200s.

A12 Engine

Should I build up my A12, or just get a bigger engine?

Building up your A12 can be quite fun and very educational. However, it will generally be more expensive than getting a larger engine. You could easily spend $2500-$4000 USD building up the A12. Also it will generally mean time that the car is not driveable, while an A14 engine swap can be done in a weekend.

On the other hand, if you find used parts, you could keep the cost down. Even adding a turbo is inexpensive if you do all the work yourself. Paying to have a shop do it usually costs around $2500-$4500 USD.

So what kind of performance increase can you expect? For $2500, you could drop from the stock 20-sec 1/4 time down to 17 seconds. That will make the car feel twice as fast. See discussion.

A-series Nissan Engines

Similar engines in the Nissan A-type series are the 1974-and-up A12, A13, A14, A15 and A12A. All fit in the 1200 with only minor changes. These are by far the most popular swapping candidates, since they just about slide right in. Other pluses of the A-series are: light weight, smooth running, and availability of racing parts. These are all excellent engines, but the bigger displacement of the A14 and A15 means more power/torque than the A12, A13 or A12A.

The A12A uses the "short block" casting as the A12 and same stroke as the A12, but uses 75mm bore instead of 73mm. NOTE: bore of the A14 and A15 is 76mm. reference: Nissan Competition catalog. The A12A is not to be confused with the Japan/Australia A12 from 1974 up. The "A12A" is the official designation used by Nissan USA for the 1980-1982 1237cc engine.

A12A comparison data

12200-H8500 CRANKSHAFT ASSY B310 A12S, A13S
12200-H1000 71-73 A12 (superceded by H8500)
12200-H5001 A12 -7909 (replacement but different)
piston w/pin
12010-H8661 A13 std 8011-
12010-H9022 all Canada A12A, USA 0879-0780
12010-H9512 USA A12A 0880-
Rod
12100-H8500 A12, A13, A12A
12100-H1000 71-73 A12

A14 GX Engine

A15 Engine deck

A15 Engine (left side)

1974-up engines have the motor mount bosses in a different place compared to the 1971-1973 A12 engines. So the engine mounts are a bit different. This photos illustrates the difference:

Stock left-side mount in Datsun 1200, but Newer A12 engine. A better way is to move the brackets on the engine, to get the engine lower. You could also 1) use the 1974-up ute crossmember or 2) modify the crossmember. For more details, see Fitting Datsun A14 & 15 Engine

What's Better? A14 or A15?

It depends on what you mean by 'better':

A14 often have better availability, meaning you can find one at an inexpensive price. <li>A15 has 7% more capacity than the A14, meaning an automatic power increase in low and mid-range RPMs, all else being equal <li>A14 and A15 stock bottom ends can both rev to 8,500 rpm so there's no advantage there. <li>Since both use the same cylinder head, there is little top-end power advantage with either engine</ul>
Other Nissan Engine Swaps

Sometimes you just want a bigger engine. After all, there's no replacement for displacement. Or maybe you come across an engine for free or very inexpensive price.
- Discussion: A Series? L Series? or CA?
Following are some popular swap choices:

L-series OHC fours

The Nissan L-series engine (as in the 1600/510) e.g. L16, L18, L20B.
NOTE: The L20B is taller though so not commonly used, but it will fit under the hood. Nissan put the L14 in the Japan-only PB110. A super-rare racing engine was the LZ20 twin-cam, fitted to 1200 racing cars.
L18 fitted
LZ20 DOHC engine

Z-series engines

Z18ET turbo, Z20, Z22. These crossflow-headed engines are based on the L-series. All install into a 1200 more or less the same way.
The nice thing about the Z18ET is its a factory setup, legal in most Australia states for a 1200. The downside is how available is it, including the wiring harness?
Z18T Turbo Engine
Z20 NAPS-Z engine
Supercharged NAPS-Z engine
Turbocharged NAPS-Z engine

E-series OHC

E15 or E16 OHC engines. These are plentiful in mid-80s Pulsars and Sentras, are similar to the A15 and have plenty of go-fast parts available.

KA-series

A less popular swap is the KA24 engine, this is a big one! at 2.4 liters. The main downside is that it is fairly heavy. The KA24 is based on the L-series engines. One or two club members have swapped this into their 1200s with good success, reporting 14.0 second 1/4s with a stock motor. Reportedly, a stock KA24DE can handle a fair amount of turbocharger boost, but not as much and doesn't rev as high as the SR20DET or CA18DET. So it's a good engine for street use, but the others may be better for high-dollar supercar buildups. There isn't much information on this swap into 1200s, so here are some links to 510 swap information: Datsuns.com 510 swap info
Fiveoneoh.com:
In stock form [the KA24] produces a large amount of power and impressive torque compared to the L-series motor. It would take a very carefully built L-series motor to equal the power and torque of the KA24. It has a very fair redline and will easily spin the tires in lower gears. If you are converting from the average L20b with mikuni's or built L16/L18 you will be happily surprised.

KA24E in Datsun 510

CA-series
- The CA20 looks promising as it's a big 2.0 liter four similar to the A-series, but it has a poor reputation
- CA18ET SOHC (not DOHC) turbo engine
CA18ET. See CA-Series Engine Swaps

L-series Six-Cylinder

Very rare is the Nissan inline-6 L20, L24, L26 and L28 engines, for example Ron Folck's L26-powered (260Z engine) 1200 race car
L-six requires major mods

High-power Turbo Fours

The advantage of these engines are that they are fairly lightweight (being fours) and in stock form give more power than the A-series engines. But it does take considerable craftsmanship to fit one in including the intercooler.
How efficient are these engines?
This chart shows that the FJ, CA and SR Turbo engines are twice as efficient than most engines in the matter of power/weight ratio. I estimate a 300 hp CA18DET (282 pounds) would weigh just over half that of 300 hp GM V8 (500 pounds).
Of course, the easiest way to go fast is: less weight, more power. These turbo fours deliver.

CA18DET

There is a lot of information in the main forum on all aspects of the CA18DET swap.

SR20DET

The SR20 can bolt-in without cutting the firewall, though it's easier with an originally automatic-equpped car (which has a bigger central tunnel).
Discussion: AFRacer's journal of SR20DET Swap into Left-hand-drive 1200

FJ20DET

The F20DET engine was basically a detuned race engine, a bit heavy but possibly Nissan's strongest ever engine. The stock engine can take massive boost and survive, while turning out incredible horsepower

V6s and V8s?

Yes, V6s and V8s can be swapped into Datsun 1200s (and have been!), with increasing amounts of crafting and modification required. Your 1200 won't handle curvy roads too well with all that weight up front, but that's not the point of this, eh?
Ford Windsor 302/5.0 V8
GM Chevrolet 'smallblock' V8
Nissan VG30 V6 (also available as VG20, VG33, etc)
Chrysler 392 Hemi V8

Challenge Engine Swaps
The following are not known to have been successfully completed: