Engine Swap FAQ --(Adam Gibson)

[old forum]

Ok, you want to know what engine to go, well you have quite a few choices, the simples and easiest swap, is of course to modify the stock Isuzu G161 motor, these can be made to go fast, 9.6:1 compression, stage 2 camshafts, and a fairly extreme head job, with some big arse valves and preferably a port-matched set of manifolds, with extractors on the dirty side and preferably a Weber or two on the clean side. (Motor $0-$50, rebuild $750-$1750) But, and it is a pretty major but, you would be pretty crazy to do that, instead, ring around your wreckers, all of them, then search the trading post, and find your self a G180, 1.8 litre SOHC, 8 valve engine, out of old Holden rodeos and jackaroos, this will give you a 15% or so increase in capacity and as such, you will notice the difference in both power and torque. Best of all this motor will drop straight in, on the same engine mounts, using the same ancillaries (inlet gear, exhaust, distributor, alternator, starter motor etc etc etc.) it is more or less the same as the G161 but one size bigger. This motor however, will soon leave you yearning for more power, so before putting it in, or in six months time, you will want to do all the things I suggest doing to the 1.6, bore it to 2.0, 9.6:1 compression, stage 2 cam, big big big valves, etc etc. (motor $100-$300, rebuild $800-$2000) The next step up is the G200 the same deal applies here, this time you are getting a 25% increase in capacity, a stock G200 would be quite sufficient for a good cruise mobile, but if you want to go fast do the same shit. (Motor $100-$400, rebuild $800-$2000) Also available is the G200 and G180 in twin cam versions imported from Japan, still 8 valves (2 per cylinder) but regardless a nice little motor, ring Just Gemini Spares in SA ((0 8258 7722), or try your local Jap importer, this motor is the preferred option as with the twin cam head you should be able to rev it that little bit harder, this motor, despite being practically identical won't come cheap and also, if you hot it up as above, you will have to shell out for two cams not one. (Motor $2500 ready to fly) The next step up is the stupefyingly rare 4ZD1, a 2.4 litre carbie motor that was in the rodeo for about 6 months, if you find one of these it will bolt straight up to your original exhaust manifold, inlet manifold, gearbox and engine mounts. The only trouble that may arise is clearance between its rear mounted distributor and the brake booster on your Gemini. These motors are rarer than hens teeth, an alternative is the 4ZC1 2.0 litre (from the piazza for example) minus the turbo gear. In terms of stock power, the next step is the 2.6 litre 4ZE1 out of a Holden rodeo, this is a very sweet motor, we are talking a 62.5% increase in capacity here, and you WILL feel this in the seat of your pants, pushing out around 90-100 kilowatts, that is 120-133hp to use the old scale. That may not sound like much but this motors strongest point is its torque, put this motor in and you will still be sideways at suburban speed limits. The problems you may encounter here; 1. Cost, you don't mention your financial situation, but if you are bankrupt like me, shop around, you will be told prices anywhere between $8000 and $3000 for a complete running motor with all ancillaries including freight. For a bare motor, you will be quoted anything between $2000 and $200, I am not kidding here, worst of all, the $2000 motor was in worse nick than the one I might just be getting for $200. 2. Fuel Injection, if you plan to make your car legal, it will be a lot easier if you fit the stock fuel injection gear, this is a fair bit of work, you need to modify the fuel neck so it will only accept unleaded, you will need an injection fuel pump and regulator, the stock computer, injectors, fuel rail, air flow and throttle position sensors, etc. you will need to upgrade the necessary sections of your fuel lines to high pressure hose, if you don't do this, the 60-80psi of a fuel injection system will probably cause quite a major problem and maybe even a rather huge fireball. Also, you need to watch your distributor to brake booster clearance. There is a shitload more work here, so alternatively you run carbs, this will make it A LOT harder to get your car engineered and roadworthied and insured, but it can and has been done, consult the Gemini car club in your state/area. 3. Engineering, they may just well insist you upgrade your brakes while you are at it, so I would suggest either BMW 323i brakes, off an old 4 stud Beemer, or Volvo 4 piston calipers with 10.5 inch disks, for these expect to pay around $1200 fully engineered, again, phone just Gemini spares, they can arrange delivery and will give you shitloads of advice. 4. The rest of your drivetrain, make sure your clutch works and you might want to consider a Disk Brake LSD, these aren't cheap, Just Gemini Spares quoted me $1500, but an LSD is one of the biggest handling upgrades you could ask for in a Gemini with this engine. There are other issues with this engine but it is probably still the best bang for your buck, without losing either drivability or reliability, you can get 200hp out of a G200, just not for very long, or with any torque below 4000rpm, an absolute joke for anything but competition use. The next option up is the 4ZC1 Piazza Turbo, a very popular mod, at least 5 people in your state Gemini club will have done it, and can help you with advice, again, the distributor, and the engineering issues, this motor is getting into the silly numbers for a stock Gemini suspension and brake setup, we are talking around 110kw (about 150 ponies) and a huge 225 Newton metres of torque. Ok, now those are all the motors which will fit the standard engine mounts, gearbox etc. after this we are talking BIG fabrication etc etc etc. By far the cheapest of the insane Gemini screamer setups is Nissan’s CA-18DET, out of old S-13 silvias and 180sxs, make sure you get a rear wheel drive engine... this motor makes 130kw (175-180hp) and 225Nm, this is getting scary, you will need the 10.5 inch disks up front and a disk brake LSD out back, make sure you get the 5 speed with the engine, expect to pay between $1200-$2000 for this engine, then expect another $1750-$3000 to get it road legal. The maddest of the mad engine to make your Gemini the fastest thing this side of a WRX is the Nissan SR-20DET, this twin-cam, sixteen valve, fuel injected, intercooled turbo 2 litre motor pushes out a huge 164kw in Japanese S-13 spec, that is 220hp, the s-14 and s-15 spec motors make even more, for the price of buying one of these motors you could just go buy another four Geminis, yes expect to shell out 40 big ones to get your sweaty palms on one of these babies, but no-one, anyone, will expect your Gemini to still be smoking the tyres in 5th gear, then expect to pay that much again to get it road legal, you will need the gearbox from the motor, all the fuel mods, the disk brake LSD, preferably a full suspension rebuild using high quality ball-joints and bearings, not just the ones you pick up from supercheap or autobarn, then you will be wanting some stiff (lowered?) springs at around $260, a set of thick swaybars from whiteline for $280, a full wheel alignment, preferably some structural bracing or maybe if you don't mind sacrificing the rear seats, a roll cage. This is the ultimate in Geminis, sure people have shoe-horned in V-8s and 202cu-inch motors, but in Japan people (lunatics with unlimited bank accounts) push 220-600hp out of the SR20, that is enough the snap your Gemini clean in half, if you get this motor and give it the once over with the power stick, you will lay waste to any car on the road, probably including your own....

[old forum]

What the hell are paragraphs?