What factory downdraught intake manifolds, exhaust manifolds, and carbs fit and still work well on the A15?

Got an A15 in a ute I bought, has extractors which are in poor condition and the Weber is making it drink $190 worth of unleaded per 1275 k's.

Has anyone got the jet sizes of the standard a15 carb?

There are some pretty vast answers for those questions. You need to confirm bolt pattern or better yet, head type to clarify. (oval, round, H89, H75, GX?)

These might help:

Intake Manifold

Exhaust Manifold

Carburettor specifications

The best manifolds are the ones that came with the engine. Better exhaust manifold can be a GX, A12T or A15E manifold.

Best intake manifold is the type that does not not drop down and the type that suits an A15 oval port head (assuming you have an oval port head).

Sounds like your Weber needs a decent tune, depending on how you drive you shouldn't lose too much economy. Going back to original carb is a downgrade. I'm not even sure how that economy compares to standard might have to have a look through the tech section.

Weber Carburetor

Yeah I cant say for sure what it does and doesnt have till I get it home. I'm guessing its the most common head with a standard intake with weber adapter plate on it.

I looked thru the tech wiki on the standard Hitachi carbs for the a12's 14's and 15's, really doesnt make sense that some of the sizes of some of the parts are smaller on the a15 than the a12?

The tech section says the Webers can sometimes excel the Hitachi's in fuel economy AND power, but as they say, you can't have one AND the other, it's either you have good economy or good power. I'm looking for economy.

If you want economy you cant go past the factory manifold and carbs.

But as its an A15 (tiny motor)I have found that the biggest carbs and cam you can get will still get better fuel economy than most other normal cars.

Well my proton daily (std 1.6L N/a) gets $140 per 1270k's. But enough of the off topic stuff.

Hey man

Put a few pics up on facebook of the inlet manifold and I should be able to tell ya what it is

More sweet pics of your ute too!

Quote:

Sure it makes sense. How do you suppose that a B310 with A15 can make better fuel economy than a Datsun 1200? They didn't achieve that by fitting extra large carburetors.

So the A12 Hitachi can be used on the A15 no probs?

Pics will come in 2 weeks time, will start a build thread on it.

RE:So the A12 Hitachi can be used on the A15 no probs?

you shuold be able to i just swapped over an a12 carb to a15 carb on my a12 engine and runs fine after encountering some problems but nothing to do with jet sizes!

Sweet, I've got plenty of a12 carbies, just have to build 1 good one out of about 3 haha