# Which carb to use

**URL:** http://forum.driveonwood.com/t/which-carb-to-use/7995
**Category:** Website
**Created:** [September 23, 2024, 11:30pm UTC](http://forum.driveonwood.com/t/which-carb-to-use/7995 "2024-09-23T23:30:55Z")
**Posts on this page:** 3
**Page:** 1

<div class="post-metadata">

### Author: ![rusty](https://avatars.discourse-cdn.com/v2/letter/r/f17d59/32.png) [@rusty](http://forum.driveonwood.com/u/rusty)
#### Post date: [September 23, 2024, 11:30pm UTC](http://forum.driveonwood.com/t/which-carb-to-use/7995/1 "2024-09-23T23:30:55Z")

</div>

Hey yall, Im woodgassifing a chev 350 and it currently has a non functioning 4 barrel rochester quadrajet that has small primaries and large secondaries. It needs to be replaced. Which type of carb is best for wood gas?  
Should i buy another quadrajet or a carb with equal size primaries and secondaries. Thanks…

---

<div class="post-metadata">

### Author: ![ForbiddenTuna](http://forum.driveonwood.com/user_avatar/forum.driveonwood.com/forbiddentuna/32/36469_2.png) [@ForbiddenTuna](http://forum.driveonwood.com/u/ForbiddenTuna)
#### Post date: [September 24, 2024, 12:55am UTC](http://forum.driveonwood.com/t/which-carb-to-use/7995/2 "2024-09-24T00:55:00Z")

</div>

You can either make an intake plenum like I did that has a separate woodgas throttle, or you could go with something that has mechanical secondaries. The square bore carbs aren’t as good on fuel economy as something spread bore like a Quadrajet.

Personally I think it’s worth the effort to have two separate throttles because your gasoline carb won’t get carboned/sooted up. I run a super tiny Holley 94 clone 2bbl for gasoline. It’s like driving with just the primaries of a QJet. I could have made it use the Dualjet 2bbl and I may do that if I find power is lacking.

A lot of guys have ran square bore carbs with woodgas through it and had no real issues. You’ll need a way to cut off the gasoline flow like a cutoff solenoid or a valve. Shut it off on the line that goes to the carb and not the mechanical pump, so you don’t run the pump dry.

---

<div class="post-metadata">

### Author: ![Norman89](http://forum.driveonwood.com/user_avatar/forum.driveonwood.com/norman89/32/39575_2.png) [@Norman89](http://forum.driveonwood.com/u/Norman89)
#### Post date: [September 24, 2024, 1:59am UTC](http://forum.driveonwood.com/t/which-carb-to-use/7995/3 "2024-09-24T01:59:09Z")

</div>

Being that I have put down like 30,000 miles on my Toyota with wood and did destroy one Holley, I would recommend a plenum hookup for woodgas instead of through the carb

Just my 2 cents. You can see videos on my build thread what happens to a Holley long term with woodgas use. Or separate front and back barrels
