WHICH EDELBROCK CALIBRATION KIT DO I NEED?
The first question that you should ask yourself is, “Do I really need a calibration kit at all?” There is a difference between adjusting a carburetor and re-calibrating a carburetor. Adjustments can be done with no additional parts and a screwdriver. Calibrating can require additional parts. That is where the kits and other parts come into play.
IS MY CARBURETOR SIZED APPROPRIATELY FOR MY ENGINE?
If you don't know the answer to this, you should check. A carburetor that is improperly sized to an engine may never run right.
IS MY CARBURETOR INSTALLED PROPERLY?
This includes using the proper carburetor to intake gaskets and making sure there are no vacuum leaks. Fuel pump pressure that is too high can also lead to problems. The output of a stock mechanical fuel pump is often too high and can range from 3-15 PSI. An Edelbrock carburetor does not need fuel pressure more than 6 PSI, and pressures over that can cause overfilling of the bowl and other problems. Many people think they have a problem with heat soak but they are really running their carburetor too lean. If you already know that you need to tune richer and have heat problems, your heat problems may go away after you tune richer. If you truly think that carburetor heat soak is a problem and you are not running too lean, heat soak should be eliminated before tuning.
DO I UNDERSTAND HOW TO DO BASIC CARBURETOR METERING ADJUSTMENTS AND HAVE I DONE THIS CORRECTLY?
If you can answer “YES” to all of the the questions above, continue reading.
DOES MY CARBURETOR NEED TO BE REBUILT?
Carburetors can act funny if a passage is blocked or if something is gunked up. Many people start changing metering and rods and jets when all they needed to do was clean a carburetor out with compressed air or carburetor cleaner.
STOCK VERSUS MODIFIED ENGINES
Edelbrock carburetors often run well right out of the box with little to no adjustments when the proper size carburetor is installed on a stock engine. When an engine is modified, there is a higher chance that your carburetor can benefit from re-calibration.
I ALREADY KNOW ALL THIS, WHAT KIT DO I NEED?
The kits Edelbrock has put together for a specific carburetor are actually chosen well to provide a variety of different options for your specific carburetor. These will provide different rich and lean configurations that you can choose from. If you know that you will never go leaner with your carburetor, there is no benefit to you from the parts in the kit that will make your carburetor leaner. For rich conditions, vice-versa. If you know what direction that you want to tune (rich or lean) then you can decide if a kit is worth it to YOU.
Look at what parts in the kit you will actually use. If you know you might use at least half of them, getting the kit is probably a good choice. If you have no idea if you need to go richer or leaner, what are you going to do when you have the kit in your hand? If you are just going to try different combos and see what works, then get a kit.
You're in a better position if you know about what sizes of jets, rods, and springs that you need or want to try. If a kit doesn't have those sizes, don't get that kit.
Look at what parts in the kit you will actually use. If you know you might use at least half of them, getting the kit is probably a good choice. If you have no idea if you need to go richer or leaner, what are you going to do when you have the kit in your hand? If you are just going to try different combos and see what works, then get a kit.
You're in a better position if you know about what sizes of jets, rods, and springs that you need or want to try. If a kit doesn't have those sizes, don't get that kit.
EVERY PART IN EVERY KIT WILL FIT IN EVERY EDELBROCK CARBURETOR.
1403 - Calibration Kit 1486
1404 - Calibration Kit 1486
1405 - Calibration Kit 1479
1406 - Calibration Kit 1487
1407 - Calibration Kit 1480
1409 - Calibration Kit 1488
1410 - Calibration Kit 1480
1411 - Calibration Kit 1489
1412 - Calibration Kit 1480
1413 - Calibration Kit 1480
1801 - Calibration Kit 1486
1802 - Calibration Kit 1486
1803 - Calibration Kit 1486
1804 - Calibration Kit 1486
1805 - Calibration Kit 1840
1806 - Calibration Kit 1840
1812 - Calibration Kit 1841
1813 - Calibration Kit 1841
1825 - Calibration Kit 1842
1826 - Calibration Kit 1842
1404 - Calibration Kit 1486
1405 - Calibration Kit 1479
1406 - Calibration Kit 1487
1407 - Calibration Kit 1480
1409 - Calibration Kit 1488
1410 - Calibration Kit 1480
1411 - Calibration Kit 1489
1412 - Calibration Kit 1480
1413 - Calibration Kit 1480
1801 - Calibration Kit 1486
1802 - Calibration Kit 1486
1803 - Calibration Kit 1486
1804 - Calibration Kit 1486
1805 - Calibration Kit 1840
1806 - Calibration Kit 1840
1812 - Calibration Kit 1841
1813 - Calibration Kit 1841
1825 - Calibration Kit 1842
1826 - Calibration Kit 1842
WHAT PARTS ACTUALLY COME IN A CALIBRATION KIT?
Calibration kits come with:
Metering Jets
Metering Rods
Step-Up Springs
Metering Rod Retaining Springs
Metering Jets
There are four metering jets in a 4 barrel carburetor. Two are primary jets and two are secondary jets. Primary and secondary jets are interchangeable. A larger jet means that more fuel will be delivered. A smaller jet means that less fuel will be delivered.
Metering Rods
Step-Up Springs
Metering Rod Retaining Springs
These hold the metering rods in place. These are reusable and are already in your carburetor. You can use the ones in the Calibration Kit if you bend or break the ones already installed in your carburetor.
I already know I am running too (Rich or Lean), what parts do I need?
This is a great situation and where you should be if you are re-calibrating. There are a few different ways to change a tune, but if you really consider what you are trying to do it will make it much easier. It helps to think about tuning in 3 different states:
Idle to low cruise (high manifold vacuum)
Acceleration (low manifold vacuum)
Wide Open Throttle (or WFO)
If you are only trying to tune out a hesitation or bog on acceleration…
Metering Jets
Metering Rods
Step-Up Springs
Metering Rod Retaining Springs
Metering Jets
There are four metering jets in a 4 barrel carburetor. Two are primary jets and two are secondary jets. Primary and secondary jets are interchangeable. A larger jet means that more fuel will be delivered. A smaller jet means that less fuel will be delivered.
Metering Rods
Step-Up Springs
Metering Rod Retaining Springs
These hold the metering rods in place. These are reusable and are already in your carburetor. You can use the ones in the Calibration Kit if you bend or break the ones already installed in your carburetor.
I already know I am running too (Rich or Lean), what parts do I need?
This is a great situation and where you should be if you are re-calibrating. There are a few different ways to change a tune, but if you really consider what you are trying to do it will make it much easier. It helps to think about tuning in 3 different states:
Idle to low cruise (high manifold vacuum)
Acceleration (low manifold vacuum)
Wide Open Throttle (or WFO)
If you are only trying to tune out a hesitation or bog on acceleration…