Dual Quadrajets ?

Posted By: 383man

Dual Quadrajets ? - 11/09/13 06:43 PM

Got my latest issue (Nov 13) of Muscle Car Review and it has a nice write-up about Dick Harrel and Nickey Chevy and how they put a 427 in one of the first Camaro's in late 1966. They said with 8" slicks and 4.56 gears it ran 11.90's @ 114. But then it says they took of the single Holley carb and put 2 Quadrajets on it and ran 11.40's @ 126 ! Wow 12 mph pick up ?

Dont sound right to me but it is a cool write-up. I cant say I have ever seen anyone run dual Quadrajets either ? Ron

Posted By: fourgearsavoy

Re: Dual Quadrajets ? - 11/09/13 06:57 PM

There's a picture floating around here of a guy running dual Thermoquads on a tunnel ram.I don't see why it couldn't be done with a Q-JET

Gus

Attached picture 7917713-rearviewsavoy.jpg

Posted By: topside

Re: Dual Quadrajets ? - 11/09/13 07:47 PM

Might actually work pretty well at lower RPM, what with teh small/higher velocity primaries.
12 MPH would seem to indicate that the thing was starved for airflow with the single carb; that's a big bump, though, maybe something else was tweaked at the same time.

Posted By: 383man

Re: Dual Quadrajets ? - 11/09/13 08:03 PM

Quote:

Might actually work pretty well at lower RPM, what with teh small/higher velocity primaries.
12 MPH would seem to indicate that the thing was starved for airflow with the single carb; that's a big bump, though, maybe something else was tweaked at the same time.

Thats what I was thinking. They dont have a pic with the dual Quadrajets. Ron

Posted By: Bumbalawski

Re: Dual Quadrajets ? - 11/09/13 08:19 PM

I had talked with Ronnie Sox in the 70's at 75-80 dragway in Maryland about carbs. He mentioned they had tried dual Thermoquads on their pro stock Colt. It was quicker on both et and mph (he did not say how much), but it was not very consistent. Thus, they dropped the idea. Perhaps the quadrajets had the same problem.

Posted By: GomangoCuda

Re: Dual Quadrajets ? - 11/09/13 08:45 PM

Saw dual q-jets on a Buick in the "70's" I think the same guy had dual t-quads on a tunnel ram.

Posted By: RUNCHARGER

Re: Dual Quadrajets ? - 11/09/13 09:37 PM

12 MPH, I don't have time to do the math but what is that about 150HP at that level?

Sheldon

Posted By: '72CudaRacer

Re: Dual Quadrajets ? - 11/09/13 10:40 PM

Quote:

12 MPH would seem to indicate that the thing was starved for airflow with the single carb; that's a big bump, though, maybe something else was tweaked at the same time.

The most obvious other change would be the intake.

Did they go from a stock low, single plane cast iron intake, to a tunnel ram? And how small was the single Holley?

Brian

Posted By: WO23Coronet

Re: Dual Quadrajets ? - 11/10/13 02:43 AM

The member running the dual Thermoquads is quickd100, they're on a 605 HEMI and he loves them

Posted By: quickd100

Re: Dual Quadrajets ? - 11/10/13 03:00 AM

Yep....That be me. They cost little or nothing and with a bit of tuning they can scream.
I made 18 dyno pulls on the 528 to get them where I wanted them but it was well worth it. On the 605, IF I drive it nice it geats 10mpg. That's with 4.56 gears, 10" TA convertor, and a custom Bullet solid roller that's 288/292 duration@.050 and .767 lift on the intake.
I love thermoquads, on Speedtalk one guy quoted a Rochester Carb engineer that said; (The thermoquad is the next step in evolution of the spreadbore after the quadrajet.) Dave