Q-jet experts , couple questions

Lynn A McCarty · 11-29-2009, 01:07 PM

Holley simpler to tune? If you call up Mike Beachy and get the hanger adjusting tool he makes, you can tune the carb with simply changing the hanger once you get close with metering rods and jets. I dont see how you can get any simpler than that?

Power? I have been on at least 6 different dynos. A 800 to 850 Holley loses power on our SSers every time. That includes the expensive flowed boosters and all. The only carb that has ever out HPed the Q-jet is the 1150 with all the max tuned flow boosters and venturi. That was only 7HP.

Why do we use the Holley then? For measurements only with the Super Flow air bonnet. It screws with the vent tubes and the secondary air horn. We have found to relocate the air flow mechanism and relocate it as far away from the carb as possible, then making a custom Q-jet carb bonnet helps. The secondary air horn still doesnt like it.

Bob Pagano · 11-29-2009, 01:10 PM

Lynn its a bracket car, they dont look at the same things we do, it would still be cheaper to run a holley.

Lynn A McCarty · 11-29-2009, 01:17 PM

I have bracket guys running Q-jets and the love them. You dont have th carry a bucket full of jets and gaskets everywhere you go. You can get away with substandard fuel delivery with a Holley due to the larger fuel bowls and inlets, but otherwise the Q-jet is pretty damn cheap.

I spent a lot of time with the Q-jet guys in Rochester, NY. You guys wouldnt believe the technology of a Q-jet. They still state that the Q-jet was the closest carb to actual fuel injection ever made.

Mark Yacavone · 11-29-2009, 01:33 PM

For the record, I wasn't advocating a Holley carb for anything, unless the user's application required a bunch more CFM.
I doubt that's the case here.
More specifically, I'd rather see him cobble and hack up a Holley, rather than a good Q- Jet.

Redlight · 11-29-2009, 08:10 PM

Thanks, so far, I think?

I guess I have to tell he "rest" of the story. I have been running with A Holley.

Trying something different, a set of Q-jets on a old Offy intake.

The carbs are Buick bases, Chevy bodys and Pontiac tops so alot of the cobbling had been done.

I dug around my library and low and behold, found Roe's book circa '81.

Giving myself a refresher.

I will keep them away from the bridgeport for now.

Oh Lynn, they are sitting on a Pontiac!

Neil Smedley · 11-29-2009, 11:39 PM

I have put a 750 holley on a few stock elim cars just to see how fast they could REALLY go.......granted, a high dollar q-jet will perform just as well but who wants to spend the bucks ?

Bruce Fulper · 11-30-2009, 02:37 AM

Quote:

Originally Posted by Neil Smedley

I have put a 750 holley on a few stock elim cars just to see how fast they could REALLY go.......granted, a high dollar q-jet will perform just as well but who wants to spend the bucks ?

Neil:

How dare you be rational? Only true engineers know how to cross the dyno finish line first.

hahaha...!

Hope all's well in r-e-a-l h.p. land.

c-ya

Glenn Hayes · 11-30-2009, 09:06 AM

Quote:

Originally Posted by Lynn A McCarty

I have bracket guys running Q-jets and the love them. You dont have th carry a bucket full of jets and gaskets everywhere you go. You can get away with substandard fuel delivery with a Holley due to the larger fuel bowls and inlets, but otherwise the Q-jet is pretty damn cheap.

I spent a lot of time with the Q-jet guys in Rochester, NY. You guys wouldnt believe the technology of a Q-jet. They still state that the Q-jet was the closest carb to actual fuel injection ever made.

Lynn,
What is the ideal fuel pressure to have for the Q-Jet ?
What is the best S.B. Chevy performance intake manifold to use and modify ?

Glenn

Redlight · 11-30-2009, 11:22 AM

"Rational" or not

, I am going to use the Q-jets.

I would appreciate if we stayed on topic, not Holley vs..........

The fuel system is up to par, all Mallory components, proper size line to and from (return), good wiring etc etc. Fuel is steady and feeds 630 hp just fine.

The present pump is a 140 but have a back up 250 if it is needed.

Greg Hill · 12-01-2009, 09:36 AM

If you are changing from a Holley to a q-jet you will need a better fuel system. The mallory 140 pump probably will not do the job. The 250 with a 1/2 inch line is the minimum.

11-29-2009, 01:07 PM	#1
Lynn A McCarty Member Join Date: Jun 2002 Location: Plainfield (INDY) Indiana Posts: 468 Likes: 1 Liked 3 Times in 3 Posts	Re: Q-jet experts , couple questions Holley simpler to tune? If you call up Mike Beachy and get the hanger adjusting tool he makes, you can tune the carb with simply changing the hanger once you get close with metering rods and jets. I dont see how you can get any simpler than that? Power? I have been on at least 6 different dynos. A 800 to 850 Holley loses power on our SSers every time. That includes the expensive flowed boosters and all. The only carb that has ever out HPed the Q-jet is the 1150 with all the max tuned flow boosters and venturi. That was only 7HP. Why do we use the Holley then? For measurements only with the Super Flow air bonnet. It screws with the vent tubes and the secondary air horn. We have found to relocate the air flow mechanism and relocate it as far away from the carb as possible, then making a custom Q-jet carb bonnet helps. The secondary air horn still doesnt like it. __________________ Lynn A McCarty 3470 SS

11-29-2009, 01:10 PM	#2
Bob Pagano VIP Member Join Date: Jun 2002 Location: New Holland, PA Mooresville,NC Posts: 1,163 Likes: 242 Liked 16 Times in 11 Posts	Re: Q-jet experts , couple questions Lynn its a bracket car, they dont look at the same things we do, it would still be cheaper to run a holley. __________________ Bob Pagano A/SA

11-29-2009, 01:17 PM	#3
Lynn A McCarty Member Join Date: Jun 2002 Location: Plainfield (INDY) Indiana Posts: 468 Likes: 1 Liked 3 Times in 3 Posts	Re: Q-jet experts , couple questions I have bracket guys running Q-jets and the love them. You dont have th carry a bucket full of jets and gaskets everywhere you go. You can get away with substandard fuel delivery with a Holley due to the larger fuel bowls and inlets, but otherwise the Q-jet is pretty damn cheap. I spent a lot of time with the Q-jet guys in Rochester, NY. You guys wouldnt believe the technology of a Q-jet. They still state that the Q-jet was the closest carb to actual fuel injection ever made. __________________ Lynn A McCarty 3470 SS Last edited by Lynn A McCarty; 11-29-2009 at 01:21 PM.

11-29-2009, 01:33 PM	#4
Mark Yacavone Veteran Member Join Date: Mar 2002 Location: Miles From Nowhere Posts: 7,820 Likes: 2,910 Liked 5,129 Times in 1,956 Posts	Re: Q-jet experts , couple questions For the record, I wasn't advocating a Holley carb for anything, unless the user's application required a bunch more CFM. I doubt that's the case here. More specifically, I'd rather see him cobble and hack up a Holley, rather than a good Q- Jet. __________________ "We are lucky we don't get as much Government as we pay for." Will Rogers

11-29-2009, 08:10 PM	#5
Redlight Junior Member Join Date: Aug 2009 Posts: 23 Likes: 0 Liked 0 Times in 0 Posts	Re: Q-jet experts , couple questions Thanks, so far, I think? I guess I have to tell he "rest" of the story. I have been running with A Holley. Trying something different, a set of Q-jets on a old Offy intake. The carbs are Buick bases, Chevy bodys and Pontiac tops so alot of the cobbling had been done. I dug around my library and low and behold, found Roe's book circa '81. Giving myself a refresher. I will keep them away from the bridgeport for now. Oh Lynn, they are sitting on a Pontiac!

11-29-2009, 11:39 PM	#6
Neil Smedley Member Join Date: Feb 2002 Location: Phoenix, AZ Posts: 163 Likes: 32 Liked 22 Times in 7 Posts	Re: Q-jet experts , couple questions I have put a 750 holley on a few stock elim cars just to see how fast they could REALLY go.......granted, a high dollar q-jet will perform just as well but who wants to spend the bucks ?

11-30-2009, 11:22 AM	#9
Redlight Junior Member Join Date: Aug 2009 Posts: 23 Likes: 0 Liked 0 Times in 0 Posts	Re: Q-jet experts , couple questions "Rational" or not , I am going to use the Q-jets. I would appreciate if we stayed on topic, not Holley vs.......... The fuel system is up to par, all Mallory components, proper size line to and from (return), good wiring etc etc. Fuel is steady and feeds 630 hp just fine. The present pump is a 140 but have a back up 250 if it is needed.

12-01-2009, 09:36 AM	#10
Greg Hill VIP Member Join Date: May 2006 Location: Louisville , KY Posts: 1,995 Likes: 69 Liked 279 Times in 68 Posts	Re: Q-jet experts , couple questions If you are changing from a Holley to a q-jet you will need a better fuel system. The mallory 140 pump probably will not do the job. The 250 with a 1/2 inch line is the minimum. __________________ Greg Hill 4171 STK