quick fuel 750s

[Barry_R]

I think you are giving him good guidance.  Probably first step is to try them as delivered before making the jet change - then work the package from there.

[Falcon67]

Good info - why I'll request some help because the single in question here is a ProForm down leg DP body with QFT blocks.  I need to pull it apart to get the specs on the blocks.  I'll be switching to methanol later, but would like to have the gas carb at least in the ball park.  A similar unit runs on the door car, first step is to jet this one like that one - may work even though the target motor is 100+ HP over the other. 

[427LX]

If you don't have one...get a good A/F ratio reader like the AEM. This will show you where the air/fuel ratio going as you make changes on the idle/part throttle circuit. With some dual quad intake manifolds you will be able to run with a leaner cruise A/F ratio than with a single 4 bbl. intake depending on carb and engine size.
For street strip use leaning more to street...it's better to work a smaller carb a little harder than to have slower air flow thru a larger carb during part throttle.

[Barry_R]

Yeah, in no way do wish to insult or talk bad to you Barry.
As stated, many ways to skin a cat. Being that you have some
Skin in the game I’ll happily let you walk him through getting
His purchase usable.

Do not delete your original data - - it is too valuable to not have out for reference.  As you mentioned - there are a LOT of ways to skin this proverbial cat, and some comparative information can and will help as he works his way through sorting the carbs out.  The customer service side of QFT has suffered somewhat since Holley asserted control of that company, and the guy on the phone there may not be as able to approach tuning as they once were.

Also as mentioned - the very first step is to get back to the as delivered setup to establish a firm baseline - squaring up idle throttle settings and float levels are an obvious requirement, and should have been done on an air box prior to shipment.

[Stangman]

ok so I was finally able to get a look at the carbs. First thing I did was put the 72 jets in that
I took out before I even drove it. I took Drews advise and just opened the transition slot a smidge on
the back carb and just closed on the front, adjusted the floats to a smidge over a half in sight glass
and adjusted the idle mixture screws. Idle was alittle high by that time 1150 so I lowered it to 950-1000.
In gear its 850-900. Took it for a ride and it ran MUCH better, Im actually going to put 74s in and I think it will
be perfect. So the long and short of it is the problem was me. I was in a rush that day started it up and it was rich
probably because the transition slots were open alot the bowls were to the top of the sight glass I was in a trailor
which made it worse and I was getting late for work. So I jumped the gun and made some rash decisions.
I would like to thank everyone who helped me and steered me in the right direction. Even though Im not done
tuning Im in the right direction now. Again thanks guys!!! 

[Barry_R]

Good to hear that you have a workable baseline. 

As you get some driving time you will find areas in the fuel delivery that you will want to change and enhance.  The carbs have a wide enough range of adjustability that you should be able to address any issues you find.  As long as you keep good records you do not need to fear making changes - you can always "go back".  A wide band will give you hard data to use as guidance - but the old fashioned butt-o-meter will eventually win the day.  When tuning here I use O2 to get things in a safe and predictable zone - then I "feed it what it wants to eat" for power and behavior.

[Stangman]

Thanks Barry and all who replied