Newbie here, longtime lurker. Anyway, it is time for a new carb on my 67 Chevelle. 327 with a turbo 350 and a 4.11 gear. 327 specs are 10.5-1 compression, 477/477 lift 226/226 duration cam, edelbrock rpm intake, headers recurved point ignition. 2500 rpm stall. Currently I have a Holley 700 double pumper that is tired. I am looking to put a new carb on. Square bore or spread bore carb ok as I have both type of intakes. Please keep in mind this car is used a a street cruiser, reliability is more important than absolute power. THANKS

holley 650

Double pumper or vac secondary? Or does it matter? THANKS

don't do a double pumper. I'd stay with vacuum. If you read on holley site they have a faq on mech vs mac. Vac for auto and not a lot of gear, Mech for manual and a lot of gear. You can read more on their site smile.gif

Use a Holley 6210; spreadbore double-pumper. Gotta be one of the best street carbs ever built, although it'll give up a little power to a square carb. You've got plenty of gear, and enough stall for a man sec carb; I wouldn't get too hung up on vac secondaries. You don't need to make that much of a sacrifice.

Id say 650 vacuum secondary,buuuuuuuuut!!it does have 4.11 gearing,a dp might just be the ticket ,does the car have a stock stall converter?,if it does,go with the vacuum secondary--67rat

oh it has a 2500 stall converter,hey I had some 650 spead bores in my time,the best on my 68 gto 400 4speed 4.10 gear,it worked great,as posted,that might be the best,small primarys for economy(yea ok)and big secondarys for the hammer--67rat

Which is better Holley or Barry grant?

since reliability is more important to you than horse power,Id go holley,just because of cost,opinions will vary here,and im not putting down bg parts,just seems more cost affective to go holley,I dont think the difference will be worth the extra loot--67rat

use a 650 double pumper,4777-(whatever it is now}, and forget the Barry Grant stuff.Look at it this way,all the Barry Grant stuff is just an offspring of Holleys stuff anyway.........stick with the original,not the imitator. :cool:

What heads and valve size?
Any port work done?

Off hand I would say Holley 650-700DP
Or Holley 750 3310 VS.

That 700 DP is the perfect power carb. I don't see small block guys using that 700 cfm enough.

With that kind of compression, are you running pump fuel? You might need some "tunability" in any new carb you run, so keep this in mind.

Spread bore? What is the idle vacuum? If greater than 12", a stock QJ should great. Might need to pop the top to richen the primaries some. Autozone $180-220last I heard.You'll want the cool GM heat insulator set up too. $16last time I bought one. QJoption. GREAT carb. Has no reputation of being finicky, a very elegant metering device ascompared to most, but a bit devlish on the dissassembly to tune. If need be.

Me?I'd rebuild the 700 DP for sure. You can play a little game by bumping up the PV rating, cutting back the primary jetting ( and might need a squirter change ), to lean the carb out some for cruise. On high compression street engines I like 085/095/105 PV ratings. Swap the 065 for an 095 and drop jet size 2. Just make sure you get enrichment when you stomp on it,even if its a bit rich,to keep pinging at bay.

Or, if you have $400 clams buring a hole in your pocket a 670 cfm Avenger or equiv should work.

For the record, I do not prefer "chrome"carbs. Not that my sense of asthetic has any bearing here. smile.gif

I vote for the 3310 750 vacuum sec. Holley
Works better on a 350 then most people think.

Originally posted by mr 4 speed:
I vote for the 3310 750 vacuum sec. Holley
Works better on a 350 then most people think. 2nd that! 750 vac sec worked soooo much better on my small block 350 than my doulble pumper. Motor had 11 to 1 compression and a 550 solid lifter and hailed a$$...mike :cool:

66L79,

You might want to consider "re-working" your 700 Holley that you already have. A 700dp sounds about perfect for a HOT 327. graemlins/thumbsup.gif

You can send that carb to JET Performance and have it custom modified to your combination. I have had 2 carbs modifed by them (4781 850cfm and a HP950) with very good results. Should be cheaper than buying a new carb and you will be sure that it will work corrctly on your 327.

Give them a call.

http://www.jetchip.com/

66L79,

A 650 would be a better choice size wise for your combination. A 650 should give you better throttle response, torque, and acceleration. If your stall speed is at or above 2800 go mechanical secondary, if it's below that go with a vacuum secondary carburetor.

I got the old 700 dp holley off the chevelle, on my new 327 in the 62 truck,cut it back a bit,but it works great,rebiuld the 700 holley,and see how she works out--67rat