Foxy Green Foxbody Build

A simple way to check if your IFRs are too big is to stick a little wire in them to restrict the area.
Try something like a .015 wire, which you should able to get out of a stranded electrical cord.
Bend the wire in an "L shape so the wire sticks out of the IFR opening and sits on the surface of the metering block, where it will be trapped by the gasket.
That should change your idle AFR and place your idle screws in a more advantageous place.

Maybe just try it on the primaries to see how it works.

Currently the ifr's are 33s. Just for reference
 
Hey steeb, the internet says if you're rich, change air bleeds, if you're lean change restrictors. And we know the internet is never wrong. Thoughts on that?
 
Hey steeb, the internet says if you're rich, change air bleeds, if you're lean change restrictors. And we know the internet is never wrong. Thoughts on that?

It's more complicated than that, as you could see from watching the Freiburger (SP?) video.
He could've gotten that 750 to run great, but it wasn't worth the work when the 600 was just easier.
You'll pretty much always see the change you expect from changing the IFRs, but the bleeds can do funny things.

Think about this: just about every Holley-type carb is supplied a little rich, but by now they know enough people change IFRs that they make them adjustable.

I'm not sure if ATM customizes your carb based on your specs.
If they don't your carb may be set up more for strip or a bigger engine.
If so, the idle circuit may be set up too rich.
33 sounds close, I ended up with 31 on my carb.
Idle looked even better with a smaller IFR, but that made the transition circuit too lean.
 
Hey steeb, the internet says if you're rich, change air bleeds, if you're lean change restrictors. And we know the internet is never wrong. Thoughts on that?
That's fair for the idle circuit.
Not a main circuit, you'll just change the fuel curve on the main circuit that way.
 
Hey steeb, the internet says if you're rich, change air bleeds, if you're lean change restrictors. And we know the internet is never wrong. Thoughts on that?

You need to get the right combination to get your idle mixture screws in the one to one and a half turns out range, when correctly adjusted.

In your case you could try either a larger air bleed or a smaller IFR. You could possibly get away with a smaller IFR but bleeds are easier to change. If you're going to change bleeds with the carb on the car, stick some clean rag in the carb so you don't have to worry about dropping a bleed on to the butterflies. What size idle air bleeds do you have in the carb now?
 
You need to get the right combination to get your idle mixture screws in the one to one and a half turns out range, when correctly adjusted.

In your case you could try either a larger air bleed or a smaller IFR. You could possibly get away with a smaller IFR but bleeds are easier to change. If you're going to change bleeds with the carb on the car, stick some clean rag in the carb so you don't have to worry about dropping a bleed on to the butterflies. What size idle air bleeds do you have in the carb now?

I'm going with the assumption that Fox doesn't have the assortment of stuff...
 
I'm going with the assumption that Fox doesn't have the assortment of stuff...
I think that's a fair assumption, an air bleed kit by itself is a bit of an investment for use on one carb. It's criminal what Holley's charging for some of this stuff now, I'm glad I bought my stuff many years ago.
 
I think that's a fair assumption, an air bleed kit by itself is a bit of an investment for use on one carb. It's criminal what Holley's charging for some of this stuff now, I'm glad I bought my stuff many years ago.

I've done all my stuff with taps, micro drill bits, and the brass allen set screws from McMaster.

Setting up the drill press for that stuff is pretty much the reason I got really interested in machining.
 
I've done all my stuff with taps, micro drill bits, and the brass allen set screws from McMaster.

Setting up the drill press for that stuff is pretty much the reason I got really interested in machining.

I did some of that too, moved the IFR from the upper position to the lower using 6-32 brass allen screws. I also have 8-32 to do the PVCR but haven't used them yet. I had to get my allen screws from over your part of the world, hard to find over here and they want drug money when you do find them. I have a HP conversion body on my carb with screw in bleeds so I bought the Holley bleed kit, otherwise I probably would have used the 8-32s for them as well.
 
I did some of that too, moved the IFR from the upper position to the lower using 6-32 brass allen screws. I also have 8-32 to do the PVCR but haven't used them yet. I had to get my allen screws from over your part of the world, hard to find over here and they want drug money when you do find them. I have a HP conversion body on my carb with screw in bleeds so I bought the Holley bleed kit, otherwise I probably would have used the 8-32s for them as well.

McMaster needs to open an Aussie branch!

It's pretty weird, that stuff probably comes from China, so it gets shipped here and then they have to ship it back to you.

For my newest carb I bought BLP blocks and a Quickfuel body so the only tapping I did was for the TSRs, which I don't know is necessary but I figured go ahead and do it before I put it together...
 
I did some of that too, moved the IFR from the upper position to the lower using 6-32 brass allen screws. I also have 8-32 to do the PVCR but haven't used them yet. I had to get my allen screws from over your part of the world, hard to find over here and they want drug money when you do find them. I have a HP conversion body on my carb with screw in bleeds so I bought the Holley bleed kit, otherwise I probably would have used the 8-32s for them as well.
Holley HP carb body air bleeds are 10-32. The set screws work good.
 
Prepare for stupity. I head back for the car in 2 weeks. Questions aplenty will ensue. If you haven't put me on ignore yet, do so now. Although, someone tell Bob to take me off ignore so he can contribute
At least we know that we will have pages of car content coming.
 
Prepare for stupity. I head back for the car in 2 weeks. Questions aplenty will ensue. If you haven't put me on ignore yet, do so now. Although, someone tell Bob to take me off ignore so he can contribute

Why did TheBob put you on ignore?
 
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