From the simple and cheap off the shelf parts to the expensive custom made parts. When you decide you want more power and understand the cost including the loss of gas mileage and more noise you will decide what parts to start with. Bolt-ons are simple modifications that are simple to install with out a major hassle or complicate tools. This is a good starting point for the beginner that wants more power with out having to jump into the internal workings of the power plant. If you are in to engine swaps and are looking for some general information on what fits what you can find some of that here too.

Honda Civic Performance Modifications By Robin Marshall

Easy Stuff.

Firstly, the Civic 1200 engine is a very strong little machine which has high rev capability. To exploit this some good cheap modifications which can be made easily are the fitting of a sports exhaust and perhaps a Weber carburetor. The sports exhaust is easy enough, with a set of extractors, a hotdog and a turbo tailpipe should give you a bit more power by freeing accumulation of exhaust gases. Genie make a good tailpipe, the hotdog can be bought pretty much anywhere. As far as extractors go, well in Australia there is a header pipe made by Hurricane, as far as I know this is all there is for the Civic 1200.
Installation of a Weber is where real performance comes from at this level, note that this is not really effective without a decent exhaust system. We have used two types of Weber, the best seems to be the 32 DGV model which is an aftermarket carburetor used on just about everything up to 2 Liters. DON'T believe anyone when they tell you this is the wrong carburetor for a little Honda, from my experience so called experts haven't a clue about the capabilities of these cars! On my own Civic I have a 32 DIR 21 model which comes from a Renault 12, I think my a father picked it up for about 40 $AUS from a wreckers.
Fitting it is pretty easy:
Tear off the old carburetor and air filter.
Get an adaptor plate, Lynx make one for a Datsun 1200 for about 25 $AUS, that is the one to use. Since Dattos use the same Hitachi carburetor, obviously this will work.
Get another air filter, we have tried lots of tricks here but the best seems to be the RamFlo type filters, once again they cost about 25 $AUS.
To install the accelerator cable is possibly the only difficult thing here. First get a piece of metal about 1 inch wide by 4 inches long and about 4-5 mm thick. drill a hole in either end about 8mm or so (I am not sure about this). Bash this bit about until it looks like this :
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With a hole in either end this can then be attached with the intake manifold bolts and the accelerator cable can be screwed into the hole at the top. Voila instant bracket...

More Difficult stuff.

After we made the above modifications my father started to get carried away and contracted the speed bug. Other areas which he improved were the mostly to do with the cylinder head.
Firstly Installing a new camshaft will give you a lot more power and more free revving. A 30 degree cam (15 degrees each way) will be made from a good original Civic cam by a machinist. In Perth, Western Australia there is a place called Camshaft Engineering who will do it for about 70 $AUS, they will also etch the cam with some chemical (I can't remember the name) which ensures that the oil is picked up and kept on the cam.
Adjusting the advance curve on the distributor is another little trick to add some more responsiveness to the Civic. This is something that once again you will need a shop to do unless you have the right machine. By changing the counterweights and springs in the distributor the advance mechanism can be easily changed.

Switching and Swapping Cylinder Heads.

This a more radical modification which needs some clever thinking and careful machining. My father did this and was once again told by some 'experts' that it could not be done. Okay simple lesson in Civic 1200 engines. The EB1 and EB2 engines have a smaller combustion chamber than the EB3 okay? Right, and each have similar compression ratios. By fitting the right valve springs and shaving off some of the face, an EB1 or 2 head can be fitted to a EB3 block. This will boost your compression ratio so AVGAS or some other high octane fuel will be needed. This is then followed up by machining the head in order to match your exhaust and inlet ports to the header and manifold respectively. Opening these up helps the engine breathe as does polishing the ports. Be careful not to damage the inlet manifold by shaving off so much metal you get into the water jacket or bad things will happen. This is a really risky thing to do, as far as I know my father may be the only person to do it, I wouldn't know but married to the previously mentioned modifications will give you a very high performance engine.

More Ideas

A book called HONDA PERFORMANCE HANDBOOK by Glenn Marston from Motor books International ISBN 0-87938-387-9 is really useful and outlines similar modifications that I have and more, other Hondas are also covered.
How about getting a Honda City Turbo 1200 engine and sticking it in a Civic.....

DISCLAIMER

Anyone who makes any of these modifications is taking the life of their engines into their hands and also possibly violating emission laws in their Country/State. I will not be held responsible for the use of any of this information whether or not you blow up your engine.

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