Holley vs Quadra jet?
Thread Starter
Burning Brakes
Joined: Aug 2001
Posts: 1,002
Likes: 0
From: Bay City MI.
Holley vs Quadra jet?
I was at our Corvette show this past weekend and was talking to a guy about Big blocks and carburetors. I told him mine had a 850dp and he said thats way to much carb for everyday driving. He was running a Quadra jet 750 and he loves the way it runs. He gave me the old formula about engine size and rpms, and where do you do most of your running. He said his quadra jet is tons more responsive and still has good top end. Am I missing the boat here with my 850 when I don't run it up to 6k all of the time?
Drifting
Joined: Nov 2002
Posts: 1,665
Likes: 1
From: Ontario
Re: Holley vs Quadra jet? (467-Ratman)
You could always just put on a Qjet, spend 3 months tuning it to run properly and then see if its any better, that is if you can remember what it ran like with the Holley. :crazy:
Race Director
Joined: Apr 1999
Posts: 15,136
Likes: 477
From: NM
Re: Holley vs Quadra jet? (467-Ratman)
The advantage of a Holley is at the track where you can easily change jets between runs. But for the street a Q-Jet is more then enough. You don't try to change jets between stop lights so.... :)
If you have a holley, then keep it unless you are having problems and are going to replace it anyway. If you spend alot of time at the track then go for the Holley or a Dominator. If you don't go to the track, the Q-jet is all that you need.
tom...
If you have a holley, then keep it unless you are having problems and are going to replace it anyway. If you spend alot of time at the track then go for the Holley or a Dominator. If you don't go to the track, the Q-jet is all that you need.
tom...
Drifting
Joined: Nov 2000
Posts: 1,428
Likes: 0
Re: Holley vs Quadra jet? (Boofers)
You could always just put on a Qjet, spend 3 months tuning it to run properly and then see if its any better, that is if you can remember what it ran like with the Holley. :crazy:
Melting Slicks
Joined: Oct 2000
Posts: 3,023
Likes: 2
From: TEXASTEXASTEXASTEXAS TEXASTEXASTEXASTEXAS
St. Jude Contributor
Re: Holley vs Quadra jet? (tnt76vette)
:iagree: I quote the Lord of Carbs (Lars):
"Discussing which carb brand is "best" is a bit like discussing whether Mopars are better than Chevys (although we both know the real answer to that...). Any two carbs of similar cfm capability will run comparably if they're both set up right. A properly set up Q-Jet will outperform a bad-running Holley.The opposite obviously also holds true."
JB
"Discussing which carb brand is "best" is a bit like discussing whether Mopars are better than Chevys (although we both know the real answer to that...). Any two carbs of similar cfm capability will run comparably if they're both set up right. A properly set up Q-Jet will outperform a bad-running Holley.The opposite obviously also holds true."
JB
Thread Starter
Burning Brakes
Joined: Aug 2001
Posts: 1,002
Likes: 0
From: Bay City MI.
Re: Holley vs Quadra jet? (tnt76vette)
My car runs great, but its the old question is there something out that is better? I know one thing for sure with my Merlin heads with big mama intake runners and rect ports it just loves the gas!
Le Mans Master
Joined: Sep 2000
Posts: 5,635
Likes: 4
From: Orlando Floriduh
Re: Holley vs Quadra jet? (Alwyn678)
A correct Q-jet is a much better carb.. A generic rebuilt Q-jet will drive you crazy and may NEVER be right. A new Q-jet from Edelbrock is an excellent choice.
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Race Director
Joined: Nov 2000
Posts: 11,872
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From: Waterloo ontario Canada
Re: Holley vs Quadra jet? (467-Ratman)
While I don't like Holleys that is all I run because I KNOW them. I regularly seem to be buying new carbs and I spend almost a full day per carb taking the brand new holley and going through them. Mostly I am leaning all circuits outs and remaching the bad castings. Out of the last 3 new ones I bought I had 2 bad ones that wouldn't have made it without my finding the problem and fixing it.
Luckily the local speed shop gives me almost full price on trade ins.
Luckily the local speed shop gives me almost full price on trade ins.
Drifting
Joined: Mar 2001
Posts: 1,600
Likes: 0
From: Valencia (near LA) CA
Re: Holley vs Quadra jet? (467-Ratman)
"Discussing which carb brand is "best" is a bit like discussing whether Mopars are better than Chevys (although we both know the real answer to that...). Any two carbs of similar cfm capability will run comparably if they're both set up right. A properly set up Q-Jet will outperform a bad-running Holley.The opposite obviously also holds true."
While I don't like Holleys that is all I run because I KNOW them.
Every good hot-roder knows how to make a Holly work.
A Q-Jet can get the job done, but it is much easier to get it done with a Holly.
At least that is what I have discovered trying to get my engine put back together again. Everyone I talked to thought I was crazy for trying to use a Q-Jet, when the Q-Jet didn't work, i said screw it! and now I'm having a custom Holly built.
~Jay
Melting Slicks
Joined: Oct 2001
Posts: 2,064
Likes: 1,382
From: Halifax, Nova Scotia, Canada
Re: Holley vs Quadra jet? (467-Ratman)
I'll take a shot at answering this question.
As was stated, on the street, every day driving, almost any carb will work well. Even a 2 bbl.
In the 80's, gas crunch, I experimented with different size carbs, for gas milage mainly.
It always came down to the same thing. Unless I had the 750DP Holley on, then I didn't have much "go" above 5000 rpm.
I've been using the same Holley 750DP for 32 years now. It's still working great.
Yes, I know, that in every day driving you don't see those kind of rpms.
HOWEVER, when I did put my foot in it I wanted it to perform like I know it could.
And yes, the figures say that a 750DP is too much carb for a 350.
Like Norval says, if you take a Holley apart and build it correctly for your application you can have the best of both worlds.
I enjoy a very streetable car and have excellent power. 13.02 @ 110.3
Just a word on gas milage, as the DP gets a bad rap on this.
I recently took a 500 Mi. trip in the Vette. Travelling highway @ 70 mph, no playing, I got 19.5 MPG. (That's based on Imperial gallons)
Keep the Holley. You WILL be dissappointed with a Qjet.
(Not that there is anything wrong with a Qjet)
My views, Thanks
Barry
[Modified by Barry's70LT1, 12:43 AM 7/16/2003]
As was stated, on the street, every day driving, almost any carb will work well. Even a 2 bbl.
In the 80's, gas crunch, I experimented with different size carbs, for gas milage mainly.
It always came down to the same thing. Unless I had the 750DP Holley on, then I didn't have much "go" above 5000 rpm.
I've been using the same Holley 750DP for 32 years now. It's still working great.
Yes, I know, that in every day driving you don't see those kind of rpms.
HOWEVER, when I did put my foot in it I wanted it to perform like I know it could.
And yes, the figures say that a 750DP is too much carb for a 350.
Like Norval says, if you take a Holley apart and build it correctly for your application you can have the best of both worlds.
I enjoy a very streetable car and have excellent power. 13.02 @ 110.3
Just a word on gas milage, as the DP gets a bad rap on this.
I recently took a 500 Mi. trip in the Vette. Travelling highway @ 70 mph, no playing, I got 19.5 MPG. (That's based on Imperial gallons)
Keep the Holley. You WILL be dissappointed with a Qjet.
(Not that there is anything wrong with a Qjet)
My views, Thanks
Barry
[Modified by Barry's70LT1, 12:43 AM 7/16/2003]
Melting Slicks
Joined: Apr 2000
Posts: 2,145
Likes: 1
From: Ft. Walton Beach, Fl USA
Re: Holley vs Quadra jet? (467-Ratman)
Nothing at all wrong with a Q-Jet. I drive my car (17.3mpg avg on the Hot Rod Power Tour) and race it (8.02 eighth mile, 7.30 w/N2O). I can't see that it could do much better with a Holley or even a Demon. It may, but I'm completely satisfied with my Q-Jet. It probably helps that I know how to tune/work on it. My combo is relatively mild in comparison to many but it appears to perform at least as well as many bigger cammed, Demoned or Holleyed combos. I think once you start getting up around 500hp you should use another type carb but below that level a Q-Jet can be tuned to run very well at the track as well as on the street. I don't even change the setup most times from racing to just driving around.
Safety Car
Joined: Jul 2002
Posts: 3,770
Likes: 3
From: St Louis MO
Re: Holley vs Quadra jet? (467-Ratman)
I like Holleys cause I've used them on past hotrods and know the basics. However, within the next coupla years, I WILL be injecting this motor with some sort of aftermarket unit.
Brett :thumbs:
Brett :thumbs:
