Which Carburetor? Pick by What the Engine Is For
Four families on this page, and they are built for genuinely different jobs. Buying the biggest one is the most common and most expensive mistake:
- Weber 32/36 progressive — a daily driver and mildly built motor carb. Only the primary barrel opens at light throttle, which is why it gives better low-end power, drivability and fuel economy than a worn factory carb rather than just more top end. The right answer for most trucks.
- Weber 38 — a two-barrel synchronous carb: both barrels open together. Built for a modified engine, and the choice when you want hard acceleration and increased low-end torque. On a stock engine it is more carburetor than the motor can use.
- Weber DCOE sidedrafts, 40mm, 45mm and 48mm — the full-race route. Infinitely tuneable through interchangeable calibrated parts, and the standard other carburetors are measured against. These are for built engines and people who intend to tune.
- Holley 500 CFM and Street Avenger — the alternative to going Weber at all, including an Ultra XP 2bbl.
Two Things People Discover After the Carb Arrives
- Fuel pressure. The Weber 32/36 kits are listed as requiring 2.5 to 3 lbs of fuel pressure — far less than an EFI system makes. Factor in a regulator kit, and if you are converting a formerly fuel-injected engine to a sidedraft you will need a low-pressure pump, which is not supplied with the carb.
- Manual or electric choke. Most Weber kits come both ways at slightly different prices. Electric is the easier daily-driver choice; manual gives you control and one less thing to fail.
Smog-Legal Kits — Check the Years Carefully
If you live somewhere that tests, two kits are listed as smog legal and both carry specific year and drivetrain fitment, narrower than the rest of the page:
Both use a new genuine Weber 32/36 DGAV and ship as a complete conversion — carb, manifold adapter, filter adapter, linkage and installation kit. If your truck has to pass a test and your year is outside those ranges, ask us first rather than assuming; the non-smog kits are not a substitute.
Complete Conversion Kits
These include the adapter, filter adapter, linkage and install hardware, so the carb bolts to a 20R or 22R without sourcing parts separately:
Both the 32/36 and the 38 are also sold as the carburetor only, if you already have a working adapter and linkage.
Sidedrafts
40mm, 45mm and 48mm DCOE systems, each supplied with carb, filter and linkage brackets. Size to the engine, not to ambition — a 48 on a stock-displacement motor will be slower everywhere that matters.
Holley
Including the Holley 500 CFM Ultra XP 2bbl, a 500 CFM in unmodified form, and the Street Avenger.
Tell Us the Year and We Will Confirm It
Give us the year, 2WD or 4WD, whether the engine is a 20R or a 22R, what has been done to it and whether it has to pass an emissions test — we will confirm the carburetor and the fuel pressure it needs before you order. Related parts are in carbureted fuel and air.