Foxy Green Foxbody Build

Carb stumbles if I blip the throttle, then recovers and revs a touch. Initial timing is 16*

I'll have to check accelerator pump and verify it's setup right and go from there. Didn't seem to matter if I moved the timing a couple degrees either way.

This was with water Temps 175/180. It doesn't get any warmer than that
 
89 Fox 427 said:
Carb stumbles if I blip the throttle, then recovers and revs a touch. Initial timing is 16*

I'll have to check accelerator pump and verify it's setup right and go from there. Didn't seem to matter if I moved the timing a couple degrees either way.

This was with water Temps 175/180. It doesn't get any warmer than that
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Would you consider sharing your cooling specs with our friend Bruce @bruce69camaro ? He's been having some cooling issues with his Cameero. Thank you for your attention in this matter.
 
Summit triple pass radiator with 26x19 core. Derale 4000cfm dual fans. Meziere 55 electric water pump. I only had one fan running the entire time, no need to turn on the second one.

Other things to try: buy heads that are too small, carb that's too small, cam with too much duration, and run the car when it's 46 degrees outside. Also, ask if his car is dot to dot
 
89 Fox 427 said:
Summit triple pass radiator with 26x19 core. Derale 4000cfm dual fans. Meziere 55 electric water pump. I only had one fan running the entire time, no need to turn on the second one.

Other things to try: buy heads that are too small, carb that's too small, cam with too much duration, and run the car when it's 46 degrees outside. Also, ask if his car is dot to dot
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Don't you ever change who you are. You're perfect no matter what the girls say. :)
 
89 Fox 427 said:
Plumbed in a catch can. Will pull vacuum from back of carburetor

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Did you consider a vacuum pump? I think I have an Aerospace pump in the garage still . I took it off before I got rid of my old bracket car. Im never going to use it. If you want to pay shipping you can have it.
 
89 Fox 427 said:
Anything less than a dominator and you're a pussy.

ATM said my setup is right between 750 and 850 recommendation and either one would be indistinguishable on the street. 850 with annular makes it flow 800-820, so that's where they ended up
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Yeah, that sounds right.

I looked at the ATM site 'cause I want a vacuum 650-680 for my heavy car but unfortunately all they sell is mechanicals.
 
Steve439 said:
Yeah, that sounds right.

I looked at the ATM site 'cause I want a vacuum 650-680 for my heavy car but unfortunately all they sell is mechanicals.
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I'm wondering if the stumble is because it's only opening the primaries until 50% throttle. You know how the internet is. Seems a dual plane might be better to have 1:1 throttle blades opening but I'm not a carb guy
 
Fastfox750 said:
Did you consider a vacuum pump? I think I have an Aerospace pump in the garage still . I took it off before I got rid of my old bracket car. Im never going to use it. If you want to pay shipping you can have it.
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I wanted one, checked the price, bought this turd for $30 instead. Not thrilled about it sucking back into the carb but needed some kind of vacuum this go around
 
Looking good! The recoated rims look better.
I may have razzed you before but all in jest.
Glad to see you posting.

Edit:
I took a phone call while posting!
If driving on the street, I don't think you want 1:1 linkage. I have a 750DP that I converted to 1:1 for drag race only. It's responsive but I'm using a TB and not street driving. I would let other people that raced my car that it will get away from you quick in the burnout, they always smirked.
Well, watching them do the burnout the shift light would always come on!😬
Get with the builder or a guy that can tune it out.
 
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89 Fox 427 said:
I wanted one, checked the price, bought this turd for $30 instead. Not thrilled about it sucking back into the carb but needed some kind of vacuum this go around
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LMK when I get back home I will see if I still have it.
 
Steve439 said:
Now, Blu... Some of our members can be a little bitchy, but it's not nice to call them girls.
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I was wondering if anyone would catch that. :p
 
89 Fox 427 said:
Added lighting to help me get pulled over

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Probably write you up for no rear view mirror too. Which I suppose is better than getting written up for an obstructed rear view mirror with some fuzzy dice and a garter belt hanging off it.
 
M120X said:
Looking good! The recoated rims look better.
I may have razzed you before but all in jest.
Glad to see you posting.

Edit:
I took a phone call while posting!
If driving on the street, I don't think you want 1:1 linkage. I have a 750DP that I converted to 1:1 for drag race only. It's responsive but I'm using a TB and not street driving. I would let other people that raced my car that it will get away from you quick in the burnout, they always smirked.
Well, watching them do the burnout the shift light would always come on!😬
Get with the builder or a guy that can tune it out.
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Thanks for the tip.

I'm not fuckin with builders or tuners. I'm doing this shit myself. Trying to learn why and how on my own this time with internet advice and a little guess and check.
 
89 Fox 427 said:
I'm wondering if the stumble is because it's only opening the primaries until 50% throttle. You know how the internet is. Seems a dual plane might be better to have 1:1 throttle blades opening but I'm not a carb guy
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No, this is one time where I'll give black and white advice - that's not the problem.

It's probably the primary accelerator pump squirter size or the cam that drives it.
For me that stuff is the most difficult stuff to tune.

I would call ATM and ask them.

To blather about it a bit (I don't know what you know so I'll start from scratch):

Your primaries and secondaries both have pumps that squirt a shot of fuel into each of the venturis as you press the gas pedal.
This is needed because the mixture leans out for various reasons and the carb needs extra enrichment.

It works by a little plastic cam that's on the throttle blade shaft, which operates a mechanism to send fuel through the squirters.
There are several different plastic cams, all of which operate the mechanism in a slightly different manner.
Some send fuel at different rates, some send different amounts of fuel.

The squirters also come in different opening sizes, so they send in the fuel faster or slower.

So you need to optimize the squirter size and the cam shape to get your engine the correct amount of fuel at the correct time as you press the throttle.
 
Get yourself an AEM or similar wideband and put one in your car. Hell, I have one in my everyday Buick, love them! You will get to see exactly what is happening. Most likely a lean spot, but you never know until you actually know. I felt my Buick laying-over at full throttle after a few seconds, found the thing was going down to 9.2 A/F. Those dumb fucks send it way rich as a catalytic convertor saver. Would never have known what was happening without the wideband. I was able to tune that out.
 
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