Foxy Green Foxbody Build

Ha, I just got on to say I overlooked the pump adjustment last night...

Like Boss says - the feeler gauge stuff is just to make sure you're not pressing the pump too far.
The important thing is to make sure the pump lever moves immediately when the throttle is pressed.
So yes, zero at idle is what's important.
You don't want tension, just back off until there's play and then turn until all play disappears.
Then you can do the feeler gauge check.
I've never had one that failed that check after I set the mechanism for no play.
 
Ah jeez - something else I forgot is the transition slots.
You generally want the end of the transition slots under the primary side blades to look like a square.
Let me find a photo...

images
 
The problem people run into with a big cam is they need to open the primary blades too much to get the idle correct.
Opening the blades too much exposes too much of the transition slots and messes up off-idle response.
This is the reason that some people end up drilling holes in the blades - it lets more air through without having to open the blades as much.

What I do is square the primary slots and use the secondary blades to set idle speed.
People may disagree and they may be right...

Your carb may also have a feature which lets extra air through, you can look at the doc - it should explain it.
I've never owned a carb with that feature so I have no experience with it.
 
Correct .015 with it wide open.

Transfer slots look good. I'm watching the video posted by Freiburger and I need to take it off and see if secondaries are an option. He was discussing air bleeds for his off idle stumble when I left for errands. Will continue later
 
89 Fox 427 said:
Correct .015 with it wide open.

Transfer slots look good. I'm watching the video posted by Freiburger and I need to take it off and see if secondaries are an option. He was discussing air bleeds for his off idle stumble when I left for errands. Will continue later
Click to expand...
Yes. But zero tolerance at an idle ?
 
89 Fox 427 said:
Correct .015 with it wide open.

Transfer slots look good. I'm watching the video posted by Freiburger and I need to take it off and see if secondaries are an option. He was discussing air bleeds for his off idle stumble when I left for errands. Will continue later
Click to expand...
Not really apples to apples because of a few things, {dominator,no power valves]but we had a bad off idle stumble on the Big block at the hit transitioning from Idle to WOT. Squirters were way too small. That being said I have a whole selection of power valves NIB that you are welcome too if you want to experiment.
 
BOSS#1540 said:
Yes. But zero tolerance at an idle ?
Click to expand...

Yep, Fox - completely ignore that feeler gauge stuff until you've adjusted it like Boss says here.

Also remember - any time you move the throttle shafts to set idle you need to check the pump adjustment, 'cause the lever is resting on a different part of the plastic cam.

TREED
 
Steve439 said:
If the secondary adjustment screw on your carb is difficult to use when the carb is installed (like a stock Holley) you can get one of these:


It puts the adjusting screw on top.

I can't easily find an image of it installed, if you want I'll take a photo.
Click to expand...

Holy shit, I just noticed the price!

That's ridiculous, I think I paid about 20 bucks for mine.

This looks to be the same thing, for... about 20 bucks.

 
He said the wide bands are showing fat.
Typically when you move the throttle and it kinda falls on it's face it's fat.
When it backfires out the carb (or throttle body) it is lean.
The beauty of a wide band, it shows you exactly what is happening.
He needs a smaller squirter.
 
The last time i ran carburetors was 1998, so i’ve forgotten everything i knew about them from back then

Most of you here probably don’t get how superior late model efi tunability is, for timing, idle, afr’s at any specific load etc.. you do it all with the laptop
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Fuck that! There's not a day that goes by that a computer or cell phone (same thing) doesn't piss me off, be fucked if I'm putting one in my car. 🤬
 
That’s what everyone thinks until you actually do it and figure out how superior it is.. and then you can never go back

An engine ecu and something like HP tuners to tune it with isn’t anywhere near as fucked up like bill gates windows is 🤣

And you’d be surprised just how reliable oem ecu’s and engine sensors are, they very rarely ever fail
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I agree with the fact that OEM ECM's are pretty much bullet proof.
I will say that I HATE using HP Tuners to tune stuff, and I have to do it on some of my own shit!
I LOVE aftermarket ECU's, specifically Holley, but I have used many.
I would never, ever put a carb on anything.
 
I gues i'm just used to HP tuners by now, i can't say i hate using it
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You are lucky! Some GM stuff does not have a real fuel table, you have to do special shit to create one, utterly ridiculous. What I can do on a Holley ECM takes me forever with HP Tuners. If I don't need the OEM ECM to talk to other shit, and I don't need OBD2 to get through inspection, the stock shit comes out and Holley goes in.
 
89 Fox 427 said:
Correct .015 with it wide open.

Transfer slots look good. I'm watching the video posted by Freiburger and I need to take it off and see if secondaries are an option. He was discussing air bleeds for his off idle stumble when I left for errands. Will continue later
Click to expand...
With four corner idling. If I have to go a hair more than square on transfer slots. I like doing it on secondary side.
 
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