What tune up would you rather have?

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yellow rose

yellow rose

Overnight Sensation
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This is an afternoon of tuning.
7BE0F80D-B20A-4B35-BB92-06098F405756.jpeg
 
Tuning or unsticking a float.
There were some issues to work out for sure.
Tell us what your working on , where it started and where it ended. lol
 
Dinner.... ? I think he fell asleep in his chair. :lol:
 
I want a tuneup nowhere as rich as the plug on the right but not as lean as the left.
 
fishmens67 said:
Tuning or unsticking a float.
There were some issues to work out for sure.
Tell us what your working on , where it started and where it ended. lol
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340 in a 68 Barracuda. Ported iron heads by lead69. Air Gap. IIRC it’s a measured 10.5:1. Mother Thumper cam. QF 750 Brawler. TTI 1.625/1.750 step headers. 4 speed with 3.23 gears.

The carb was right out of the box and as you can see it was P-I-G rich. The only things I didn’t change are the main air bleed and the idle air bleed. Everything else was changed.

It’s IMO about as good as it can get at idle and cruise, and it’s a bit fat at WOT but that’s hard to see in the pictures.

So it was a good day. Went through some brass, but I’m happy where it is for now. Later I’ll tune it for WOT.
 
What altitude are you at?
Defining some brass would help some members here with pig rich carbs. IFR, PVCR, emulsion stack etc.
 
You definitely need some serious carb tuning. I'm with everybody else, something a lot less than the right plug & just a little more than the left plug.
 
yellow rose said:
340 in a 68 Barracuda. Ported iron heads by lead69. Air Gap. IIRC it’s a measured 10.5:1. Mother Thumper cam. QF 750 Brawler. TTI 1.625/1.750 step headers. 4 speed with 3.23 gears.
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Is that the 20-601-9 ?
235/[email protected]
291/311/107 advertised ?
Is that what you brung? lol.
 
67Dart273 said:
LOLOL All a Holley knows, idle, or WFO (wide---freakin--open)
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That used to be my opinion also, but not anymore.
I have this Holley Street Avenger from a big block motor modified to run on my 5.9 and it's a sweetheart now throughout the range.
I re calibrated the idle and high speed air bleeds and everything.
Which reminds me, I could drop a little on the secondary jetting as WOT is in the mid to high 10's on the AFR.
I'd like it to be in the mid 12's at my elevation, and then in the 13's or so when I go to Phoenix at a couple thousand feet lower elevation.

Until this carb I was stuck on the Edelbrock's but not any more. :D
I doubt I would ever go back to an Edelbrock again.
 
mderoy340 said:
What altitude are you at?
Defining some brass would help some members here with pig rich carbs. IFR, PVCR, emulsion stack etc.
Click to expand...

IIRC we are about 200 feet above sea level here.

I changed and moved the IFR and cut it back a ton, reduced the number of emulsion holes by 2 and increased the 2 others by .0015. I left the PVCR where they were at .055 because I felt that was pretty close to a good starting point. I used T slot restricters at .072 and reduced the primary jets by 4 numbers and the secondary jets by 5 numbers. The IAB and MAB looked pretty good so I left them where they were (33 and 70).

I also did a bench top recurve of his distributor and once he get the new engine ready, I’ll take it home and put it on my distributor machine and fine tune that.
 
I have one QF carb and have had my hands on a couple others, all of them were pig rich, everywhere.
 
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