Best Fuel Pressure for Carburetors

One of the most important factors of tuning a carburetor – is having the proper fuel pressure to feed your carb.

Unfortunately, many folks are running fuel pumps (mechanical or electric) that push too much pressure for street use, causing a multitude of headaches, like…

- Overfilling the fuel bowl
- Flooding
- Rich running
- Hard starting
- Poor gas mileage
- Damage the needle/seat

The fix is easy – install either a pump with the proper pressure – or plumb in a regulator. As a bonus, adding a return line will improve your pump efficiency, lower fuel temperature, and significantly reduce vaporization.

And the answer to how much pressure you should be running – for a street carburetor… see below. It’s probably less than you expect, and while you (and I) are used to seeing pressures as high as 7PSI, that pressure is not best for street-performance.

Best Fuel Pressure for Street Carburetors:

- Holley 5-6 PSI
- Edelbrock 4-5 PSI
- Stromberg WW 3.5-4 PSI

Holley Carburetor Whistle Baffle Installation Tips

When installing the Holley carburetor whistle-style vent baffle, be sure to install with the step facing up – otherwise you’ll be doing the job twice due to a poor fit.

This style can only be used on center-mount floats, while the flat style can be used on center and side-mounted floats.

#renewcarbs #itsonlyoriginalonce #carburetor #carburetorrepair #detailsmatter

Funny things I’ve Seen Rebuilding Carburetors #2

Yup… that’ a soda can pull-tab from the 70s sitting in the bore of this Holley 2818 carburetor (for a 1964 Corvette).

There were actually two of them.

You can’t make this stuff up. Here’s another funny one.

Carburetor Gasket Shrinkage

Look at how dry these gaskets are, they just fell off the metering block.

This shrinkage isn’t from not running this vehicle over the winter, but rather from long-term storage – or neglect (like sitting on a shop floor for many years). It happens.

How To Fix Broken Carburetor Air Cleaner Studs

Broken carburetor air cleaner studs are common – and are easily repaired with a drill and an easy-out.

You’re going to need to use a power-tool, just do not put too much effort into it, or you can cause more troubles than you already have…

Finesse and plenty of penetrating oil like PB-Blaster goes a long way towards a successful repair. For safe measure, run a bottoming thread repair tap (not a standard tap) to guarantee good thread engagement – and prevent a pull-through. Here’s one I did on a Holley 4412-3 carburetor.

Hidden Choke Vacuum Leak on Holley Carburetors

Look for this gasket when removing the choke on your Holley carburetor.

If you see it – make sure to replace it with a fresh one each time you take the choke off.

Forgetting this little detail will result in a vacuum leak that difficult to find when everything is installed, and it will drive you nuts – but not likely anywhere else. Details matter.

Holley Carburetor Vent Tube Replacement Tips

Does the vent tube on your Holley carburetor look like this? This one was damaged in shipping.

It’s an easy fix using an easy-out tool, like the #4 pictured.

With the tool, you can remove and install the tubes. Just be careful not to crack the mounting boss, or you’ll end up with more trouble than you started with.

Also, do this by-hand, do not use a power tool! You need to have a feel for how the progress goes – once you do it, you’ll know what I mean. Unlike engine torque, more is not better here – take it easy.