Engine Sluggish 302HO

Hello all, I have an 88 Fox mustang GT with 302 roller motor. Has about 180psi of compression in all 8 cylinders. I was sick of the old efi so I carb swapped it. I put an Edelbrock rpm air gap intake, redone E7 heads, stiffer comp cam valve springs, a b303 cam, roller tip 1.6 rockers, and a brand new edelbrock AVS2 650cfm carburetor. also an hei distributor. I haven’t touched it at all. The timing is set at 10 degrees. The car is extremely slow, I’ve been in many foxbodies carb swapped and all, this is by far the slowest. Can anyone help out? This is also my daily driver. Thanks!
 
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Sorry to hear you carb swapped it, not many around here deal with carbs anymore. There is a lot to tuning with a carb, lets ask some questions first: is there a vacuum canister on the distributor? Is the carb straight out of the box? Do you have a vacuum gauge?
Oh,and what gear in the rear?
 
Sorry to hear you carb swapped it, not many around here deal with carbs anymore. There is a lot to tuning with a carb, lets ask some questions first: is there a vacuum canister on the distributor? Is the carb straight out of the box? Do you have a vacuum gauge?
Oh,and what gear in the rear?
I’m not sure what gear is in the rear. At about 70mph I’m at 2000 rpm. The carb hasn’t been tuned it was just thrown on out of the box. The vacuum advance on the distributor is capped because it was running at 46 degrees total timing and 36 with it capped off just using the springs in the distributor. And I do have a vacuum gauge. I’m just wondering if the jets in the carb are either too big or too small.
 
So your max timing is plenty, but it needs some recurving, and initial timing sounds good at 10 deg. Is that for sure BTDC?.

What type of fuel pump and what pressure are you using?
 
I am using stock fuel pump, just used adapters and a fuel pressure regulator that’s regulated to 6.5 going to the carb.
The stock in tank EFI pump? I bet if you check your plugs, the stock pump is too much for the regulator, and is flooding the car. This has not worked out well in the past.
Here is one solution. It’s still overkill for your build, but will work much better.
At your power level, Airtex makes an external pump that would be sufficient at a lower cost. I’ll check in an old car group and see if I can get back with a number.
 
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Here is a 5-9 psi and 30 gph external pump that will run a carb. (My other project needs the 4 psi version when under the hood, mechanical ones are waiting for a short production run.)
Airtex mpn194840398
 
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