I am in the final build phase of my new engine and am looking for advice on intake manifold and carb.
The car is a 66 chevelle malibu coupe.
Engine:
400 SBC bored 40 over.
All machining on the block and original crank is done.
Pistons are KB hypo's on 5.7 beam rods (all new)
Heads are new Dart Iron Eagles 72 cc chambers with 2.08/1.625 valves, 215 cc runners.
cam is COMP Cams Xtreme Energy series XE268H hydraulic flat tappet \ 268/280.
headers are ceramic coated 1-5/8" and 3" collector.
In the garage I have a dual plane intake and 600cfm holley dbl. pumper. But I am feeling that might be a little on the small size. Looking for thoughts on single vs. dual plane and carb size.

is it an automatic tranny and what is the rear gear?

This appears to be a street application based on the cam, stick with a dual-plane manifold. The Edelbrock RPM series is excellent and gives up very little on the top end to a single plane but is better on the bottom and mid-range.

If you car is an automatic with a reasonable street gear I'd go with a Holley 670 or 770 Avenger series vacuum secondary. 670 will give better driveability, 770 will be better up top giving up some around town throttle response. What percentage of your drving time will be over 5000RPM? Seeing tou live in Ct I'd get an automatic choke version. If you have 4.11 or lower and a stick you could go with a 750 dbl pmpr but these things are pig rich driving around town and don't respond well to leaning out.

Hi, thanks for the info Tom.
It is a powerglide auto tranny and the gearing is in the low 3 range, not geared real high. Looking for it to be a Sunday cruiser, not strip bruiser. I see your point on the size and with vac. secondaries as a good choice. Sounds like a good plan. I suspect that it will have all the power i need with the dual plane and 670 or so cfm as you mentioned.
I am going to stick with the hand choke though. I am kinda old school when it comes to that part. I have had too many bad experiences with auto chokes.
Thanks for the info...much appreciated!

another question...if considering vac. secondaries, any thoughts of Holley vs. Edlebrock?

friends don't let friends use Edelbrock carbs....

the Edelbrock carbs are not really vac sec, actually an air valve carb like a Q-jet, which usually work right.

Their manifolds are good though. If you're willing and able to deal with a manual choke you could run an Air-Gap manifold. They can be a little tough in cold weather but a manual choke will fix it right up. :)

thanks Tom..I have a line on a choice of a 670 holley avenger for around $250 totally rebuilt or standard 750 holley vac. for $189 totally rebuilt. Both from the same seller. What would you recommend?

I have the same combo but with a 388, and 200cc dart iorn eagles, used a 750 cfm manual choke Edelbrock right our of the box and worked great! The plugs look perfect just with the old vaccum gauge adjustment trick!

thanks Tom..I have a line on a choice of a 670 holley avenger for around $250 totally rebuilt or standard 750 holley vac. for $189 totally rebuilt. Both from the same seller. What would you recommend?

I also like the Edelbrock carbs, I have had good luck with them, but lets face it, everyone wants a Holley;) More performance oriented. Out of the two you mention, I dont think you can go wrong with the old 3310,(the 750) They're hard to beat.:thumbsup:

always appreciate the input...that is why this site rocks!
thanks

I've grown to dislike the Edelbrock AFB copy carbs over the years because of difficulty fixing secondary bogs and whatnot. The Q-jet copy I'm fine with.

If you;re willing to deal with a manual choke I'd go with the 3310 if that's the standard 750 you're referring to. One issue, those are very low prices, I'd double check that the guy is using genuine Holley rebuild kits. Many carb guys out there will use a cheaper kit. There's many well-known problems with the cheap kits.

Thanks Tom, I'll make sure and check that before I buy..

Tom, here is the listing on ebay..
http://cgi.ebay.com/ebaymotors/750-cfm-Holley-Carburetor-Bright-Zinc-Finish-3310_W0QQcmdZViewItemQQcategoryZ33550QQitemZ320093 916567

If your not worried about a choke on your carb, go with a 750 dbl pumper, AED (Advanced Engineering Design) Holley carb. This small company builds there carbs from Holley parts and makes them better with some nice add ons. They even have a build sheet and flow test every carb they build. I couldn't be happier with the way mine runs.

Nice burnout clip Brian...

that 3310 looks pretty good to me. I wouldn't run a double pumper on a small block automatic in a heavy car. Not a known good combination.

Looked good to me too so I think I'm gonna go for that one. I have a nice edlebrock dual plane it will work great on. Thanks again for the advice.
Will post some pics when the project moves along.
Since i needed to get a new flexplate, the next step is to get the 400 rotating assembly balanced and start the lower end build.

post pics all along the way, it's fun seeing how somebody goes about their build up. Always something new to see or learn.