Serious Q: Re: Carbs., Running moderate cammed 350 SBC Options

[Dr. Roger]

Got two vac secondary carbs (600 cfm smog carb and a 750) which I now know are in need of rebuilds.

The 600 runs but, on this heavily cammed engine, like *hit. Idle circuit has very little adjustability. And it's got more vacuum ports than I can count.
The 750 is a bit too much I think for the 350.

I've run 650 double pumpers with great success and am thinking about installing a 650 spreadbore. Small primaries/large secondaries.

Goal here is to keep higher velocities off idle for responsiveness and, due to engine displacement, not over carb it like if I used the 750cfm. 6K redline...

I'm about ready to go the the local parts place and plunk down some spare change on a new 650.

WWYD? =-))

Roger

Pic is the 600 smog carb....... Come hear it run.... Swap ya' for that old 650 dbl pumper..... =-)))

[Dr. Roger]

QUOTE (Sammy @ Aug 29 2005, 11:45 AM)

It all boils down to what you know. Holly carbs are popular because they are simple to fiddle with, but are notorious for flat spots and are not the most accurate. I don't like them. The only ones I ever got to work perfectly on high performance engines were the 660 center squirters (dual quad, big $$). the edelbrock carb is basically a new version of the carter AFB (a la chrysler), they are a little tougher to dial in than a holly but work better when dialed in. You can find them at any speed shop and some flaps like pep boys, I've seen em for around $280. If you can get one for $200 that is a smoking deal. Because they are new and should be close to dialed in out of the box, they are almsot a bolt on. Then there's my favorite, the Rochester quadrajet (chebby) spread bore. I am in the minority but I think they are a very good carb. Sure they are a real PITA to dial in but once setup they meter very good for a 4 bbl. Downside to them is the metering needles and having to pull the top off the carb to make changes. On my V8 car the carb i had on the car sucked so I went to the pick a part and found an 800 cfm speadbore quadrajet for $25. It only took a little tinkering to get  it to run just right. Plus the sound when those huge secondaries open up is just too cool. Whhhooooooooooo!

OK, best deal so far is $280 for the Edelbrock 650cfm.

Manual choke and out of the box ease of installation/adjustments. Remove the top of the carb for needle replacements and other adjustments. Don't have to dissassemble it.

If that's the best deal, then I'm on it. Sold. =-) (IMG:http://www.914world.com/bbs2/html/emoticons/smilie_pokal.gif)