Carburetor Question

[The1980BEAST]

My 1980 k5 has a EOM Rochester 2 Barrel, which is the worst thing for offroading. My questions are

1. To switch to a Quadrajet is there an adapter or do I have to get a whole new intake manifold?

2. If I have to get a new manifold would it be better to get a Holley T/A? Which one is better? (My diet consists of Slick wattery mud, some deeper mud, not really any thick chunky mud. Some creek crossings and some pretty steep hill climbs and some steep slick hill climbs)

 

[The1980BEAST]

no one has opinons?

 

[Big Blzn]

Here is my $.02. i have a 670 T/A on my 400sbc and it works great. Had it on some steep hills last weekend at Cleghorn and worked awsome.

You will probably get very few people on here that really like both the Holley and Quadrajets. It is either one or the other with their opinions on what is good or bad.

 

[rcamacho]

Everyone has an opinion. I run a Holley 780CFM 3310-1 on my BBC. It's been modified for off road with extended vent tubes, whistle vents and spring loaded needles. I've had zero problems with steep inclines, descents or bouncing. Almost as good as a TA.

That said, I'm sure other carburetors can be enhanced as well I just do not have experience on other manufacturers to deliver equivalent results.

 

[dyeager535]

Depends if it's one of those Q-jets with the secondaries cast shut, or if it is the "small" two barrel.

If it's the "full size" two barrel, you can bolt a Quadrajet in it's place. Otherwise time for a new intake manifold.

 

[El Larry]

Speedway Motors has an adapter to mount a 4 barrel carb in place of a 2 barrel. part # 135-1933- $19.95 looks like it should work. Holley's are real simple to work on, one plus~

 

[dyeager535]

IMO it's pointless to put a 4 barrel on a motor then choke it down to the CFM of a 2 barrel. On a Qjet, at BEST you would be cutting CFM from 750 to 300CFM, and going even further, 800CFM to 300CFM if the "big" Q-jet.

 

[jt512]

IMO it's pointless to put a 4 barrel on a motor then choke it down to the CFM of a 2 barrel. On a Qjet, at BEST you would be cutting CFM from 750 to 300CFM, and going even further, 800CFM to 300CFM if the "big" Q-jet.

Agree 100%, used 4 barrel intakes (stock, holley, edelbrock) can be had for a few dollars more then an "adapter" so if a intake change is needed dont go the adapter route.

With that said, carb opinons will vary, I have had good luck with q-jets, I had a Edelbrock that was "modded" for offroad that worked well and my brother had a holley TA on sbc jeep that worked great as well.

One piece of advice I will offer is, dont over carb it. So many people think that their engines need way more carb then it does. For a big heavy low rpm (realitivly speaking) truck you dont need a monster carb.

 

[chriskayer]

I run a Holly truck avenger, it works pretty good.....after you get it tuned....

 

[rcamacho]

Agreed on CFM - go on the lower side for better part throttle response. I'd love to be running a 670 TA on my BBC for more linear low end response.