DragRace_Ray

Before you do an engine swap, it will pay to do your research. Things like power output, availability, cost, and complexity should be considered. Another big one is buying an engine from a legitimate seller. Check the VIN against your states DMV to verify it’s not stolen, if possible. Buying an engine that’s stolen may be a good deal dollar wise but if the police get wind, your motor can be confiscated, even if you didn’t know. Plus somebody’s car got stripped for that engine and I hate to see people support criminal activity by purchasing ripped off goods. There is such a thing as karma…

There are many shops that sell imported Japanese domestic motors (JDM). They almost all universally say less than 40k. But you have no way of telling. They quote 40k because Japanese cars get a lot less miles because (a) being on an island (b) cars are more expensive to operate and the public transportation system is used more and(c) something about insurance and taxes getting higher on older cars. So a perfectly good car gets disassembled for scrap because no one wants to pay higher premiums. Consider these engines can be 10+ years old and you have no way to verify mileage, caution is best exercised.

1. Get a warranty, this may not be the best guarantee because they are typically short, like 3-6 months but it will insure your engine won’t be a bummer right out of the garage.

2. Insist the seller do a compression test AND a leak down test and report the results to you, in writing. If anything is out of place don’t be afraid to ask for a different engine. And when you get the engine, confirm the results yourself or have a reputable garage test it. If they are worse than originally reported, ask the shop that sold you the engine why and what they are going to do about it.

On any older engine, it would be wise to do some preventative maintenance, considering you have no idea what its history is.

1. Timing belt, water pump and possibly tensioner.
2. New seals. ALL new seals. Main seals, cam seals, valve cover gasket, spark plug grommets, etc. You can replace them now while it’s easy or wait to spring a leak because the 10 year old rubber deteriorated.
3. Engine mounts if you’re smart. Often, people put heavier engines in and using the mounts that have been in there and worn out will make for headaches later. The engine will sag, or move too much when the throttle is mashed
4. Check any hoses that came on the engine carefully, if possible replace.
5. Do the equivalent of a good tune up. Spark plugs, oil filter/oil, valve adjustment etc.

Okay, now which engine do you choose? Well, believe it or not, there’s quite a bit to choose from. I’ll start from cheapest/easiest and go from there. Also to consider, are partial replacements like heads and transmissions. A note to DX owners, all of these swaps will require swapping from your engines DPFI (dual point fuel inj) system to the more common MPFI (multi-point fuel inj).

D series


* The D16A6. The 88-91 CRX si and Civic si or ex.
SOHC 1.6 non VTEC. All the si owners out there know this is a good solid engine.
The 88 made 105 hp and the 89-91 made 108 hp and 100 ft/lbs. tq. You can pick up a running engine for about $500, usually with some kind of short-term warranty and a motor needing a rebuild shouldn’t be anymore than $150.
This is engine is especially something for DX and HF owners to consider. All for about the same price as the basic bolt-ons (like intake, header, and exhaust.) Especially the HF, at 62 Hp those bolt-ons would only get you, maybe, 12-15 Hp if you’re lucky. A stock si engine increases the output 43-46 hp. Does this logic appeal to anyone? Also consider picking up the SI transmission, it’s geared for acceleration vs. the DX cruising and definitely the HF fuel economy gearing.

* The JDM ZC. The term ZC covers several different engines. The types I’m aware of are:

DOHC 1.6 Non VTEC, Black valve cover. When people say ZC, this is the engine most of them will be referring to. It's rated at 130 PS(that's 128 hp) and 108 ft/lbs. of torque. Very similar to the US Acura Integra for 88-89(D16A1) but with different mounts and head. This engine is called the D16A8 and A9 in European markets. It was available in the Japanese market CRX from 88-91, remained available in a lower end Integra until 93 and is still in use in several models of Rover hatchback in England. So that means there are new ZCs out there but chances of you getting one of the older ones is more likely. This engine will bolt right in, no fabrication of mounts and no wiring problems. If youÕre on a budget, you can even use your old si ecu, exhaust manifold and transmission, but these will choke the factory quoted hp number to less.

DOHC 1.6 Non VTEC, Olive/Brown valve cover. Easily confused with the 86-87 D16a1. These make great engines for earlier Civics/CRXs. But because the mounts require some fabrication to go into the 88-91, skip this one in favor of the black valve cover. As the predecessor, power output on the fuel injected version is 135 PS. That's right, 5 more then the newer black valve cover. There is also a carb'd version making 115 PS.

SOHC 1.6 Non VTEC. This one has become more common with time. It's price(typically sub $450) makes it very attractive. It has a more aggressive cam and ecu that rates it at 118 hp. Aside from the cam and ecu, this is basically a D16a6.

I like the ZC. ItÕs DOHC design makes it rev high smoother than the SOHC Honda engines. And with adjustable cam gears, the DOHC engines are easier to tune, with better results. Many people get them expecting a drastic difference but are disappointed with the results. This could stem from several reasons. Age, worn out engine, mismatched components etc. Get a healthy engine, the ZC ecu, the short-geared transmission, and an adequate header and it will run circles around the stock si engine BUT if you remove one of those things from the equation, it will slow the ZC down. It has a little more torque than the D16A6, but not much. Where you really notice the difference is 4000 RPMs and higher and at freeway speeds.

After many years of being the cheap and easy swap, it appears supply is dwindling. Prices are up and quality is down. Quite frequently there's a wait for the next shipment to come in. But if you can find one in good shape, they're a great choice.

* The D16Z6. From the 92-95 Civic SI and EX
SOHC 1.6 VTEC. 125 hp and 106 ft/lbs tq
The D16y8. From the 96-00 Civic EX
SOHC 1.6 VTEC. 127 hp and 107 ft/lbs tq
A lot of people compare this and the black valve cover ZC when thinking about swapping engines because the price and power output are similar. It’s available domestically, which makes it easier to find and verify actual miles on an engine. There are quite a few engines floating around because people swap them out for Integra engines. There is generous aftermarket support for this model as well. And the VTEC switch over is a blast to drive through.
The block does bolt right in physically if you use your si tranny but there are a few changes to be made in the wiring.
The VTEC needs a way to be activated. Easiest thing to do is wire up a RPM sensitive switch to have it activate the VTEC at a preset RPM, like 4400. While easy, it has some drawbacks. Normally, this engine’s ecu would be used for this and when VTEC comes on, it gives the engine a richer fuel curve and makes sure oil pressure is adequate. So there is your other option, convert to the entire D16Z6 wiring harness and ecu.