Thread: Edelbrock carb problems

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Welcome to CHR and thanks for the kind words!

I really like the Edelbrock carburetors and have found them to be very dependable for daily drivers once they’re properly dialed in. I like Holleys too – but they sometimes require a bit more fiddlin’ that the Edelbrocks. That said; let’s look at your “opportunity”.

Before you do anything, verify, with a fuel pressure gauge that your pressure is between 4 and 5 psi. The floats also need to be at 7/16”, but typically they are spot on out of the box so I wouldn’t suspect them – especially in that this is carb #2 with the same issues.

The 1806 with the Endurashine is a different carburetor that the 1406 –not just in outward appearances. The 1406 is a 600CFM unit that comes stock with .098 primary jetting, a .075 x .047 metering rod and a yellow setup spring. The 1806 has .095 jetting on the primary, a .068 x .047 metering rod and an orange setup spring. The orange spring is stronger (5” vs 4” Hg) than the yellow spring and overcomes the vacuum sooner to push the metering rod to the open position.

I’d check the spark plugs and see how they look. They should be a light brown – kinda like coffee with some cream – in color. If they’re black or “dark chocolate” in color, you’re running rich. White or very light is too lean.

When you say, “….It fell on its face when hitting WOT before 2500rpm”, I get the impression that it’s bogging down and then catches up after stumbling – indicative of a rich condition. If that’s the case, it may be as simple as changing the setup springs from orange to yellow. It may also require you to go a step (or two) leaner.

The manual that comes with the carburetor is very good – but somewhat overwhelming the first few times one reads it!! The one that I have in front of me shows the 1806 on page 17. If the spring swap has no effect, I’d try going to the configuration shown as reference #16, i.e., .092 main jets and .065 x .042 on the metering rods.

You can buy the individual parts (jets and metering rods come in sets of two) from your local go-fast parts store, Summit or directly from Edelbrock. Part number 1425 for the jets ($4.39 from Summit) and part number 1416 for the metering rods ($9.25 from Summit)

Optionally, you can but a “kit” – part number 1840 ($49.95 from Summit) – that has an assortment of jets, metering rods and a complete set of setup springs. Remember that the top gasket (part number 1472 - $9.95 from Summit) is good for one remove and replace and after that, well it is suspect. If the gasket sticks at all, replace it. I buy the gaskets in a five pack (part number 1499 - $12.95 from Summit) as I got tired of needing one at 5:10 on a Saturday – ten minutes after the local shop closed!

Good luck with this one and once again, welcome to CHR

Regards,
Glenn

I agree with most of the responses. I had a 750cfm on my 350, and swaped it to a 600 cfm Edelbrock, (1406 model) and it runs like a watch. Too much carb, for a small block - unless your pumping 500 hp or better.