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1966 289 bogging down and keeps getting worse

  • Thread starter Thread starter Ihatethisdamncar
  • Start date Start date Aug 18, 2022
I

Ihatethisdamncar

New Member
Aug 18, 2022
2
0
1
Summerville SC
Aug 18, 2022
#1
  • Aug 18, 2022
  • #1
My car started doing this after taking off a cheap electric fuel pump and reconnecting the old one. Last night it would run ok until high rpm’s, but this morning it would hardly even get out the driveway. I’ve tuned the carb multiple times. I’ve replaced spark plugs, I’ve done just about everything and it seems to just get worse. Any help will be appreciated.
 

wicked93gs

15 Year Member
Sep 30, 2006
1,198
228
93
Nashville TN
Aug 18, 2022
#2
  • Aug 18, 2022
  • #2
What does your air fuel ratio look like under load?(should be able to tell by reading your plugs after shutting down the car immediately after a bog). Your plugs will at least tell if its rich or lean.
 
I

Ihatethisdamncar

New Member
Aug 18, 2022
2
0
1
Summerville SC
Aug 19, 2022
#3
  • Aug 19, 2022
  • #3
wicked93gs said:
What does your air fuel ratio look like under load?(should be able to tell by reading your plugs after shutting down the car immediately after a bog). Your plugs will at least tell if its rich or lean.
Click to expand...
It’s always ran rich no matter what I do.
 

Hot Stang

Member
Aug 19, 2022
40
16
18
Hiawassee Ga
Aug 19, 2022
#4
  • Aug 19, 2022
  • #4
Check fuel pressure. Old pump might have taken a dump.
 

Hot Stang

Member
Aug 19, 2022
40
16
18
Hiawassee Ga
Aug 19, 2022
#5
  • Aug 19, 2022
  • #5
Does your car require a return? If so you must hook one up or it will never run right. You'll be flooding your carb with fuel. I'm running stock in tank pump. Because of my return my pump runs constantly but only regulated amount of fuel goes to carb.
 

WingsOfGold

New Member
Aug 2, 2022
21
1
3
SW Virginia
Aug 20, 2022
#6
  • Aug 20, 2022
  • #6
Check the obvious......... fuel filter otherwise buy another mechanical pump.
 

Hot Stang

Member
Aug 19, 2022
40
16
18
Hiawassee Ga
Aug 20, 2022
#7
  • Aug 20, 2022
  • #7
WingsOfGold said:
Check the obvious......... fuel filter otherwise buy another mechanical pump.
Click to expand...
Fuel pressure test would tell him about filter. Same filter that was on other pump so it should be ok. It worked before.
 

WingsOfGold

New Member
Aug 2, 2022
21
1
3
SW Virginia
Aug 20, 2022
#8
  • Aug 20, 2022
  • #8
Hot Stang said:
Fuel pressure test would tell him about filter. Same filter that was on other pump so it should be ok. It worked before.
Click to expand...
In theory yes but for 5 bucks................
 
Reactions: Hot Stang

Hot Stang

Member
Aug 19, 2022
40
16
18
Hiawassee Ga
Aug 20, 2022
#9
  • Aug 20, 2022
  • #9
I find it easier to go from new school motor to old school car than it is to go other way. I'm playing hell but those 450 HP, before I add NOS, will be a wild ride in itself when I get it right.
 

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Hot Stang

Member
Aug 19, 2022
40
16
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Hiawassee Ga
Aug 20, 2022
#10
  • Aug 20, 2022
  • #10
View: https://youtu.be/z8FaAW-oXcg
 

Hot Stang

Member
Aug 19, 2022
40
16
18
Hiawassee Ga
Aug 20, 2022
#11
  • Aug 20, 2022
  • #11

400 hp 302 Small-Block - Mustang & Fords Magazine

Check out this 302 small-block making 400 hp on pump gas, only on Mustang & Fords Magazine.
www.motortrend.com


Basically my build except a few changes. You heard the gear drive. Running GT40P heads also with upgraded springs.
 
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