Ok so here's my dilema. A friend of mine is willing to sell me his A15 engine, however he sold the carb and manifold off of it a while ago. I haven't had much success in tracking down a carb and manifold for it so he said what he could do is get a gasket made that would allow me to use the carb and manifold from my A12 on the 1500 engine.

So basically what I want to know is if this will actually work and if I'll still get good performance using the A12 carb on the A15?

i think you might find that the bolt pattern for the a15 manifold will be different to your a12.
i ran a 12 carb on a a14 for a while and it ran fine you might lose a bit of power up high thats all but it wont be much

You will need to 'drill out' the carb jets, to get the proper performance.

You need a set of 'number drills' to do this.

If you drill too large, you can always solder up the jet, and redrill it.

I normally find the current size, then go one larger, and test.

This certainly worked fine for any A14 engines I ever used.

why dont you run a twin carb setup ie twin su or hitachis

I live in Barbados so twin sus are almost impossible to come by. Plus the engine will be going in my daily driver so with twin carbs the fuel economy won't be the best. I could probably source a single sidedraught weber and manifold to fit. This would still give me decent mileage and performance right?

Oh btw anyone know where I can find the jet sizes of the A15 carb? In case I have to end up drilling mine

As dattodude says, you can perfect the carb for the A15 engine. However, I ran an A12 carb on A14 engine and it ran extremely well, if anything it was a bit rich.

The main difference between them is:
* A12 fewer (if any) emission controls
* 20/26 venturis vs bigger 21/27 or 23/27 fo A15
See Carburetor specifications.

Quote:

i like to know more about this method...
can give us more details..?where to drill..
sorry i not so technical guy..
i dono which part to drill....

a picture will be nice..

Just put the carb on a drive it around. I'm sure you'll find it works fine.

If you need to know how to "tune" a carb -- which is what the drilling is about -- come back and tell us how it runs and we can give further advice.

i have stock A15 with stock DCH306 carb,
with stock exhaust system
on my B310.

how it runs..
my car are slow...
not much horsepower
and torque only available at 1k to 2k rpm
and its reluctant to rev...

Now if you have the stock A15 carb, don't even think of "drilling" the jets. That carb is good for 6,000 rpm.

Rev problem is usually either a fuel problem or a spark problem.

You should start with a full tune-up, including timing, new points & condensor, etc. Get a Sunny tune-up book and follow it carefully. They also have troubleshooting charts. You can get one from the library or bookstore.