https://youtu.be/huVFrjYMMQ0?si=WLKtBiPinSPMG3R5

 

I sure would have liked to see the test results of the Q-Jet running at the same air/fuel ratio as the EDL VRS. How can you compare the numbers when the one carb has been handicapped with the wrong WOT A/F ratio..? They even admitted at the beginning and the end that the Q-Jet was not set up right. What the..? Edelbrock slanted that test. With the same A/F ratio for a valid comparison, the two carbs would have run about as close to identical as you can get.

 

I think they got it as close as they practically coud. It may be you can't get those figures much closer.. I still don't think it would make up the deficit.

 

The two carbs were almost a full point off and different on air/fuel. That makes a significant difference. You can easily jet the Q-Jet correctly to make it achieve 12.5:1. If we jetted the EDL carb to run in the mid 11's and fixed the Q-Jet to run in the mid 12's, the results may be reversed... I've done carb comparison testing on the dyno, and we always get the jetting set up so that each carb tested runs within a tenth of a point of the other carbs in the test. The testing is otherwise pointless and invalid.

That said, the EDL carb ran exceptionally well for an out-of-the-box carb. But they intentionally handicapped the Q-Jet.

 

I'm getting ready to do a comparison myself but I'm not expecting or trying to make the Q-jet lose , I have acquired three fairly inexpensive eBays cores ,a like new electric choke 600 from Craigs-list that looked brand new including the box and all the stuff that goes with it that seller said it came with a project car he bought and 60.00 was all he was asking so I snatched it and I got one brand new AVS2 650 from Jegs.
I picked up a Edelbrock EPS 800 as this one is supposed to make 22 ft pounds more torque and I think 18 horse more power out of the box than a Holley 3310, I got a 600 manual choke to go with a 600 electric choke (they have different boosters between manual and electric choke) , picked up a like new 750 manual choke and a brand new AVS2 650 , , I will start with a AFR reading for out of the box Edelbrock and if it's anywhere close I'll do a track session for out-of-the-box set ups and then do it again tuned , my 1980 L82 Q-jet is a stock rebuild with the metering rod stop raised .025 from stock (from Lars's post ) and runs beautiful with a stock from Edelbrock un-ported 2101 intake manifold . I did turn on my Kestrel 4250 weather station/gauge and it's not working so I'll need get accurate weather info in order to have accurate testing at the track so I have to send it in or replace it before I begin, I am expecting the AVS 2 to be the best performer and street manners from the Edelbrock camp but who knows and that's why we test
On a side note the 750 manual choke carb I bought that literally looked brand new from a eBay seller that stated : I bought it new and bolted it on my car and it ran like **** and took it right back off and set it on the shelf !! Lol, honest seller and it looked brand new too and stunk like turpentine so I believe him and then took it apart , cleaned it and check the jet sizes it had and somehow it received .089 primary jets from the factory when it was supposed to have .113's , one float set high and one set low so no doubt it ran like poop .

My test vehicle will be my black 1980 L82 with a Sonnax 2.84 close ratio first gear set in a 700R4 transmission with a 2200 to 2300 stall speed, stock 3.08 axle ratio, 183 cc intake port with 64cc chamber aluminum heads on a .025 down flat top pistons , Comp XE262 cam with 1.6 rocker arms, Hedman side exit headers going to a 27 inck long 2.5 diameter glass pack side pipe ,

 

Comparing a 600 cfm carburetor to a 750 is not a comparison at all. Peak power is one thing driveability is another. Sometimes they come together sometimes not.. the new Edelbrock Holley redesign is the only Edelbrock I may consider in the future. I know I'll never have a quadrajet again. They aren't a bad carburetor but compared to my quick fuel double pumper it's soggy.
It's difficult to text different carbs there will always be a reason in someone's mind why one tests better
Maybe we should get Andy wood to have Lars set up the quadrajet to give it a better shot. But truthfully I don't think it would bridge the gap. Nothing at all against Lars I respect his work tremendously.

 

That wasn't a fair comparison. That test proved an out of the box, properly tuned carb outperformed an improperly tuned carb. I can't believe anyone with any integrity would claim one carb is superior to another without both being properly tuned.

 

The thing you all are missing is Andy woods pointed out the so called unfairness , or tuning deficiencies of the quadrajet carburetor.
Also Andy woods works as David vizards right hand man.
No need to get hurt feelings. But the quadrajet has limitations.

 

That VR is one of if not the most tunable carburetor , I ordered a 850 back when you could pre order but it took so long we ended up with a custom carb from SP Carburetors for just slightly more , Dale Meers in Kentucky received a 750 VR for evaluation back before they were ready to ship and they couldn't get the same power as their dyno carburetor a 750HP Holley but that could be a different story now but back then they were still playing with it trying to make it better , that VR is about a 1/2 inch taller than a Holley if not mistaken so if your hood clearance is a issue take that into consideration. When they are more rudely available I wouldn't trying one out

 

Here's a much better comparison. My Qjet made within 2 hp of a Holley 950 Ultra HP (80805 with 1.60" venturi and 1.75" throttle blades). The AFR for the Qjet was around 12.4 and the 950 was about 12.7. The 850 Holley was swinging for the fences at 13.7 AFR so it's not really a valid comparison.


Here is the Qjet pull, or maybe the one after:

 

Outstanding post! The dyno graph just shows that for my seat of the pants, I probably wouldn't be able to tell any differences among them and that the regular ol' QJet is a fantastic carb running with the best of them — especially in the street RPMs up to 4500.

 

Thank you. Yes, set up properly, one would never be able to tell the Qjet from the others. Except it would get better gas mileage!

 

What size Thermoquad was in your test ?

 

It started out as a production 6322S so was 850 CFM. I removed the venturis from the primary plastic bowls. Also added a rear air door stop adjustment screw. Still has both primary boosters so I would guess cfm is probably somewhere between the 850 comp series and 1000 CS.