GMC 305e Carburator Choice

[DreamRyder1963]

My brother and I are starting to think about doing some slight performance mods to his truck. The truck is running perfectly now so this is just us brainstorming for the future. I have picked up a second intake for us to work on while he continues to drive the truck. According to 60-66 GMC Guy, a 500 cfm 2 barrel Holley is a nice choice for these engines. While we both like this idea, he is still in high school and getting ready for college so money is an issue. Would a 600 cfm Holley 4 barrel be to much for this engine? I tested the fit of a 2 to 4 barrel adapter this afternoon and it fits fine. I ask because I have a spare 4 barrel right now and this would save him a nice chuck of change.

[Bob B.]

The V-6's really run well with the Holley 500 c.f.m. 2 bbl.. I don't know of anyone who successfully got a 4 bbl. on a 305, but it has been done on the large 401's and 478's. I guess all you could do is try. You might end up spending more on gasoline over time then you would buying the 2 bbl. now. The guys on the 6066GMC page are very knowledgeable about these engines.

[DreamRyder1963]

I figured it was unlikely. The more I look at the intake runners the less I think it will work.