Help !!!
Thread Starter
Instructor
Joined: Jan 2000
Posts: 231
Likes: 5
From: Arvada Co.
Help !!!
I'm going to replace my old Q-Jet carb and I'm a little confused by all the choices out there. The Edelbrock Performer looks promising but I have no clue what CFM to buy. The Q-Jet that is on the car now came off some 70's car or truck and no one has ever been able to match the part # to find the CFM rating. My engine is a 327 with camel hump heads; Edelbrock aluminum square bore manifold ; a fairly aggresive cam and is rated by the local shop that built it at 350 hp. Any help to clear up this problem would be appreciated. I've also been looking at Holly's with the same results. The motor has always run rich and does not like to idle as you cannot adjust the mixture screws.
Thanks, Kent
Thanks, Kent
Le Mans Master
Joined: Jan 2002
Posts: 8,913
Likes: 283
If it is a "square bore" then a Rochester carb, the ones I am familiar with, won't fit. They are a "Spread Bore".
I would go with a new Holley, 1850-3 series. (600 CFM with vacuum secondaries).
What type of choke system are you using now?
What cam went in the motor?
What is your idle vacuum?
Mark
I would go with a new Holley, 1850-3 series. (600 CFM with vacuum secondaries).
What type of choke system are you using now?
What cam went in the motor?
What is your idle vacuum?
Mark
Last edited by ghostrider20; Jul 3, 2006 at 03:08 AM.
Advanced
Joined: Jun 2006
Posts: 83
Likes: 0
From: Rockford MI
I purchased an Edelbrock carb a couple of weeks back (see my thread about Holley problems), but absolutely could NOT get it to fit under my air cleaner (the stock 66 SB unit). The Edelbrock carb I bought had the electric choke and it sits RIGHT SMACK in the way. The fuel inlet is also very high on the carb and would have been a problem.
If your Edelbrock intake in the standard Performer intake for a SB (#2101), Edelbrock says that this will accept either a square bore OR a spreadbore carb with no adapter plate (called their tech line and asked, since their literature was not clear).
If your Edelbrock intake in the standard Performer intake for a SB (#2101), Edelbrock says that this will accept either a square bore OR a spreadbore carb with no adapter plate (called their tech line and asked, since their literature was not clear).
Thread Starter
Instructor
Joined: Jan 2000
Posts: 231
Likes: 5
From: Arvada Co.
The lift and duration I can't tell you and to check the vacuum at idol I'll have to borrow a vacuum gauge or take the car down to the local shop. The motor was built in 98' shortly before I bought the car although it has very few miles on it. The guy who built the car might still have the specs on the cam.
Safety Car
Joined: Feb 2003
Posts: 4,068
Likes: 27
From: St. Joseph Mo
I have a Edelbrock Qjet clone (#1901?) on mine that works wonderful right out of the box. Fits under the stock air cleaner on a BB no less. (Manifold is off of a '68 passenger car.) You will have to monkey with your throttle rod. A 650 cfm capacity would be about right. 
Last edited by 67L36Driver; Jul 2, 2006 at 08:49 PM.
Advanced
Joined: May 2006
Posts: 75
Likes: 0
From: Reisterstown/ Finksburg Maryland
I am not a Holly fan, but I bought a Street Avenger with an electric choke, a while ago for my ’73 Vette and it ran really good. I since found the right Rochester, because of the cold air hood. But I did like the way Holly ran right out of the box.
Dave
Dave
Le Mans Master
Joined: Nov 2000
Posts: 7,246
Likes: 21
From: Going too fast over the hill. Iowa
The Carter wcfb and afb carbs that came on 64s are the most dependable, leak free, simple to clean carbs ever made. IMO find an old one off a 62-65 Chevy and save yourself a lot of problems.
66s all had Holley carbs but my 66 has a 65 manifold with a Carter AFB. I have had 20 years of no problems, ever since I bagged the Holley. I am currently rebuilding one that belongs to a freind with a 65 coupe. He has an Edelbrock in its place and has an aftermarket air cleaner on it. The original Carter will let him reinstall the original dual snorkel air cleaner.
Any one can rebuild a Carter for themselves.
66s all had Holley carbs but my 66 has a 65 manifold with a Carter AFB. I have had 20 years of no problems, ever since I bagged the Holley. I am currently rebuilding one that belongs to a freind with a 65 coupe. He has an Edelbrock in its place and has an aftermarket air cleaner on it. The original Carter will let him reinstall the original dual snorkel air cleaner.
Any one can rebuild a Carter for themselves.
Thread Starter
Instructor
Joined: Jan 2000
Posts: 231
Likes: 5
From: Arvada Co.
Thanks to everyone for your help and as usual all the great and valuable info. I have an aftermarket air cleaner so shouldn't have any problem with fit. I'm going to call Edelbrock and pump them for info on fit, CFM, etc.
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