Best Carb suggestions?
Le Mans Master
Joined: Jun 2008
Posts: 5,284
Likes: 235
From: Rockledge FL
keep in mind that there is not a lot of room under a BB hood, if you go to a square bore carb with the stock intake you will have to use an adapter plate. the hood probably wont close and the adapters are iffy at best supposedly.
you would have to change your intake to a square bore intake.
there are only two readily availble intakes that will work with the stock BB hood and a square bore carb.
the single plane torker II and the dual plane LS6
you would have to change your intake to a square bore intake.
there are only two readily availble intakes that will work with the stock BB hood and a square bore carb.
the single plane torker II and the dual plane LS6
Race Director
Joined: Apr 1999
Posts: 11,520
Likes: 13
From: CORVETTE 77 385 C.I. TEXAS
For 454, perf. & if you drive hard the DP spreadbore.
Race Director
Joined: Oct 2000
Posts: 15,052
Likes: 79
From: central FL, near the beach.
1. floor it in turns
2. or on ice
3 or in the rain
VS will apply power more slowly and could keep a novice driver from frying the tires and going out of control.
it is like a built in nanny watching your every move, and saying NO U CANT FLOOR IT SO FAST
CF Community Team
Joined: Oct 2004
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From: Cape Cod, Mass.
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I bolted on the Holley Spreadbore with mechanical secondaries on my 68 427/390. Felt like I gained 100 horsepower 
My Q-Jet was not functioning properly and I'm not a big fan of them anyway. The Holley is a direct bolt-on. The only problem is that the Holley is about 1/4 inch taller than the Q-Jet. I needed to use a marginally lower profile air filter in the stock air cleaner. Great low and mid-range torque. It's a 650 CFM carb and is plenty as long as you don't live at 6500 RPM's, which I don't.
My Q-Jet was not functioning properly and I'm not a big fan of them anyway. The Holley is a direct bolt-on. The only problem is that the Holley is about 1/4 inch taller than the Q-Jet. I needed to use a marginally lower profile air filter in the stock air cleaner. Great low and mid-range torque. It's a 650 CFM carb and is plenty as long as you don't live at 6500 RPM's, which I don't.
Race Director
Joined: Dec 2004
Posts: 15,029
Likes: 2
Pro
Joined: May 2003
Posts: 593
Likes: 0
From: London England
Are you sure you're not confusing progressive power and a flat spot?
Le Mans Master
Joined: Jun 2008
Posts: 5,284
Likes: 235
From: Rockledge FL
holleys carb selection software will back that up.
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Le Mans Master
Joined: Jun 2004
Posts: 6,231
Likes: 65
From: Seattle WA
St. Jude Donor '14
Le Mans Master
Joined: Oct 2002
Posts: 7,098
Likes: 378
From: Las Vegas - Just stop perpetuating myths please.
What is best choice for a stock 71 bb 4-speed? Holley and Jeggs search for 4165 comes up with 6210 w/mechanical secondaries? Holley site listed another spreadbore with vac secondaries with a number of 0-80555 but the jeggs site has no results for that number.. are Edlebrock carbs any good? Any others? I just want good dependable performance with a stock engine. I have 3 junk carbs here I have messed with all summer and it still wont run. Any specific part #s or links would be great! Thanks
They build to your cars specs then test run it on an engine.
'bout $300 for a Qjet - no core charge.
Next to a lars rebuild, best deal on planet.
Good luck,
cardo0
Burning Brakes
Joined: Feb 2002
Posts: 804
Likes: 5
From: Fresno CA
Send your Q-Jet to Sean, he's been doing them for me for years. He just did one for a 72 I have in my shop last week; got it back and put it on, a couple simple adjustments and the car runs perfect, owner couldn't be happier!
http://www.smicarburetor.com/
http://www.smicarburetor.com/
Race Director
Joined: Oct 2000
Posts: 15,052
Likes: 79
From: central FL, near the beach.
I bolted on the Holley Spreadbore with mechanical secondaries on my 68 427/390. Felt like I gained 100 horsepower My Q-Jet was not functioning properly and I'm not a big fan of them anyway. The Holley is a direct bolt-on. The only problem is that the Holley is about 1/4 inch taller than the Q-Jet. I needed to use a marginally lower profile air filter in the stock air cleaner. Great low and mid-range torque. It's a 650 CFM carb and is plenty as long as you don't live at 6500 RPM's, which I don't.
My Q-Jet was not functioning properly and I'm not a big fan of them anyway. The Holley is a direct bolt-on. The only problem is that the Holley is about 1/4 inch taller than the Q-Jet. I needed to use a marginally lower profile air filter in the stock air cleaner. Great low and mid-range torque. It's a 650 CFM carb and is plenty as long as you don't live at 6500 RPM's, which I don't..
Since qjets came on millions of cars & trucks there will always be lots of qjet endorsements. But they don't make new ones anymore.
Just like new cars, do u really want an old restored car, or a new 1970 model?
the 4165-6210 is available as a BRAND NEW 1970 carb
Race Director
Joined: Oct 2000
Posts: 15,052
Likes: 79
From: central FL, near the beach.
.
How many qjet guys have actually tried a 4165? I think many are comparing the 4778-4781 series of "competition" double pumpers. I agree they are lousy on the street.
But YOU BOUGHT THE WRONG CARB. So get your facts straight.
The 4165 is a totally different carb. Don't confuse it with the high profit margin stuff advertised in magazines, or the complaints from guys that bought the WRONG model.
Last edited by Matt Gruber; Dec 4, 2009 at 05:58 AM.
Pro
Joined: May 2003
Posts: 593
Likes: 0
From: London England
is there any logic to that? I put a 4165 on my 72 w/TH400/308 in 1994, just to test it for use on my then apart 61, well....i never put the VS back on, sold it for $20. Got another 4165 for the 61. By comparison the VS was a turd.
.
How many qjet guys have actually tried a 4165? I think many are comparing the 4778-4781 series of "competition" double pumpers. I agree they are lousy on the street.
But YOU BOUGHT THE WRONG CARB. So get your facts straight.
The 4165 is a totally different carb. Don't confuse it with the high profit margin stuff advertised in magazines, or the complaints from guys that bought the WRONG model.
.
How many qjet guys have actually tried a 4165? I think many are comparing the 4778-4781 series of "competition" double pumpers. I agree they are lousy on the street.
But YOU BOUGHT THE WRONG CARB. So get your facts straight.
The 4165 is a totally different carb. Don't confuse it with the high profit margin stuff advertised in magazines, or the complaints from guys that bought the WRONG model.
I've no personal experience with the 4165 but in my experience any carb with vacuum secondaries tends to deliver more progressive power than fully mechanical secondaries. For an average street driver this would surely be the more controllable option, where as the sudden hit of BHP from mechanical secondaries would surely be better absorbed and delivered by an auto box?
Another point here for anyone expressing an opinion is you need to be comparing like with like.
Of course replacing a 30 year old QJet with anything brand new is going to be better (assuming it's the right application).
You can rebuild a carb but unless you're going to start replacing throttle spindles, bushing and microscopically cleaning every driling and port it's never going to match up to a new carb.
Le Mans Master
Joined: Jun 2008
Posts: 5,284
Likes: 235
From: Rockledge FL
[QUOTE=Matt Gruber;1572320044]
But YOU BOUGHT THE WRONG CARB. So get your facts straight.
QUOTE]
I dont have any facts, just generalizations based on a lot of threads asking what carb to buy. which is why i relayed what is normally suggested here every time someone asked the same question. you will notice of course that i never gave my own opinion just a generalization of the accepted opinion that was already out there. so which is the bigger waster of serve space your post or my reply.
But YOU BOUGHT THE WRONG CARB. So get your facts straight.
QUOTE]
I dont have any facts, just generalizations based on a lot of threads asking what carb to buy. which is why i relayed what is normally suggested here every time someone asked the same question. you will notice of course that i never gave my own opinion just a generalization of the accepted opinion that was already out there. so which is the bigger waster of serve space your post or my reply.
Race Director
Joined: Oct 2000
Posts: 15,052
Likes: 79
From: central FL, near the beach.
Golden
u did hit on the false assumption that many make,
that anything brand new is going to be better than a 30 yr old qjet.
this is totally false. a good working qjet is near impossible to beat. the 4165 was designed from a clean sheet of paper to BEAT the qjet, when BOTH were BRAND NEW. Those that want to argue qjet vs 4165 need to actually buy and drive a 4165. Cant just refer to others that dont measure up.
Lots of qjets just need a rebuild to work really well. The OP carb is cracked and epoxy failed to hold. Time for a new 4165. There is no other new carb designed as direct replacement.
u did hit on the false assumption that many make,
that anything brand new is going to be better than a 30 yr old qjet.
this is totally false. a good working qjet is near impossible to beat. the 4165 was designed from a clean sheet of paper to BEAT the qjet, when BOTH were BRAND NEW. Those that want to argue qjet vs 4165 need to actually buy and drive a 4165. Cant just refer to others that dont measure up.
Lots of qjets just need a rebuild to work really well. The OP carb is cracked and epoxy failed to hold. Time for a new 4165. There is no other new carb designed as direct replacement.
Racer
Joined: Mar 2009
Posts: 278
Likes: 14
It has been said that the best application for our corvettes is the q-jet. With that said, Chicago Corvette specilizes in rebuilt Q-Jets. They have 1 that fits your application part # C1675 for $209.95. They do have a reputation for questionable service. BUT I HAD NO PROBLEMS WITH MY Q-Jet for my 69 390horse. If you call ask for AL @ 800-872-2446.
Pro
Joined: May 2003
Posts: 593
Likes: 0
From: London England
Golden
u did hit on the false assumption that many make,
that anything brand new is going to be better than a 30 yr old qjet.
this is totally false. a good working qjet is near impossible to beat. the 4165 was designed from a clean sheet of paper to BEAT the qjet, when BOTH were BRAND NEW. Those that want to argue qjet vs 4165 need to actually buy and drive a 4165. Cant just refer to others that dont measure up.
Lots of qjets just need a rebuild to work really well. The OP carb is cracked and epoxy failed to hold. Time for a new 4165. There is no other new carb designed as direct replacement.
u did hit on the false assumption that many make,
that anything brand new is going to be better than a 30 yr old qjet.
this is totally false. a good working qjet is near impossible to beat. the 4165 was designed from a clean sheet of paper to BEAT the qjet, when BOTH were BRAND NEW. Those that want to argue qjet vs 4165 need to actually buy and drive a 4165. Cant just refer to others that dont measure up.
Lots of qjets just need a rebuild to work really well. The OP carb is cracked and epoxy failed to hold. Time for a new 4165. There is no other new carb designed as direct replacement.
Le Mans Master
Joined: Jun 2004
Posts: 6,231
Likes: 65
From: Seattle WA
St. Jude Donor '14
The only advantage to a DP carb is in a single scenario: zero-to-WOT, i.e. drag racing. As a generalization, there are of course exceptions...and of course few people take the time to correctly tune their VSs, which skews the impression of these carbs. DPs are used nearly exclusively in racing as they're simpler and economy and driveability isn't important. It's another race part used on the street.
On the engine dyno, a VS and DP carb are going to show nearly identical results. Driveability with a VS carb on the street is going to be significantly better...but it will definitely give up ET at the strip.
I don't buy Matt's continued endorsement of the 4165 as the "end all, be all" of carbs - but it's a spread-bore, VS carb with the right CFM for the purpose, tuned for the application and a near-bolt-in swap. It's a great pick for this application, and it does have the advantage of being more easily tunable than a Q-jet. I don't want to start a Q-jet tunability p*ssing match because it's been done a billion times - but I'll just note that it's a speciality such that shops specialize in it...and that should tell even the most fanatical Q-Jet fan something.
Personally, as previously noted I'd still spend the $$$ to get the existing Q-Jet fixed as the shortest, cheapest path.
<Nomex ON>
On the engine dyno, a VS and DP carb are going to show nearly identical results. Driveability with a VS carb on the street is going to be significantly better...but it will definitely give up ET at the strip.
I don't buy Matt's continued endorsement of the 4165 as the "end all, be all" of carbs - but it's a spread-bore, VS carb with the right CFM for the purpose, tuned for the application and a near-bolt-in swap. It's a great pick for this application, and it does have the advantage of being more easily tunable than a Q-jet. I don't want to start a Q-jet tunability p*ssing match because it's been done a billion times - but I'll just note that it's a speciality such that shops specialize in it...and that should tell even the most fanatical Q-Jet fan something.
Personally, as previously noted I'd still spend the $$$ to get the existing Q-Jet fixed as the shortest, cheapest path.
<Nomex ON>
Last edited by billla; Dec 4, 2009 at 10:26 PM.