Finding the right engine - for a hovercraft!

[niky]

125ccs don't make much power. At best, I think it's about 10-12 hp per engine. The most powerful engine in the class is the Suzuki 150cc (used on the Raider) which is DOHC and oil-cooled, and that still only makes 16 bhp.

RE: iron block... yeah, that might be a problem... but most 1300-1600s here are ironblock... the engines with lighter casings (that I know of) are the Honda B16 (the block is hollow) and the Nissan SR20 (2 liter, but it's all aluminum). Unfortunately, the SR20 is still about as heavy as an iron-block 1.6, while the Honda B16 is really expensive (about 65k pesos)... either one would be very complicated in terms of wiring, which probably means you should stick to the smaller carburated engines.

I don't really know the wet weight of an iron-block 1.3, but I'm pretty sure that it's much lighter than the bigger engines available. Even if it shares a head with the higher-displacement model, the block casting of the 1.3 is different, and uses less material.

If you don't mind having a loud exhaust sound, and run the engines with open pipes, I'm pretty sure any carburated 1.3 - 1.5 liter engine (GA13, Toyota 4AFE, Mitsubishi 4G18 (is it?) or the carburated Honda D15B (makes the most top-end power here)) should work. And as long as you know how to change plugs and choke the carb, they should serve you well.

[baludoy]

nicky: how about the engines of the suzuki fronte (are parts still hard to come by for this?) and the kia pride? will they satisfy the threadstarter's requirements?

[niky]

Very little power from either of them.

I'm suggesting a more modern 1.3 because, even if they're rated at just 85 hp, once you remove the exhaust restrictions and free up the intake (which you're going to do anyway, if it's going to be installed in a watercraft), it'll be spot on for 100 bhp. Plus they're designed to run stably at high rpms, which I'm not sure the smaller engines can handle. I don't know about the Pride engine, but its successor, the Picanto, has a warning in the manual against revving it at high rpms for long periods of time.

If it's just for a boat, to turn a screw instead of running a lift-fan, heck, even a 50cc scooter engine will do.

[ghosthunter]

Pssst.... when in doubt... use old tech.

Anyone has the specifications for the 1.3L / 1.5L / 1.6L engines for the old VW Beetle? It's pretty compact and aircooled meaning it would save weight because there is no water based cooling system.

Ironically, these engines are easier to find replacement parts for than some of the newer vintage cars we have in the city.

------------------------------

Personally I would recommend an ultralight aircraft engine which is made from aluminum and aircooled. Downside I don't know where you can buy one and the last one I had access to was used in the Micro-Car 1 project back in college, about 15 years ago.