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  • 1965 - 1973 Classic Mustangs -General/Talk-
  • Classic Mustang Specific Tech

intake and carb

  • Thread starter Thread starter Mongo316
  • Start date Start date Apr 15, 2006

Mongo316

New Member
Apr 28, 2004
43
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Hamilton ontario
Apr 15, 2006
#1
  • Apr 15, 2006
  • #1
Hello all, I have a 67 stang with a 351w out of 1969 or 70 car. I just did a intake (rpm edl) and 670 street avager carb.. The car starts idle ok but when u hit the gas just a litl it spuds even while at idle it pops through the exhaust. I changed the cap and rotor to a new one. I check the float level on the carb and when i took the screw out fuel came out so i dont think the level is adjusted right, would this cause the car to run so bad?... Anyone any ideas? Please help
Mario
 
D

D.Hearne

New Member
Sep 29, 2000
11,730
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south louisiana
Apr 15, 2006
#2
  • Apr 15, 2006
  • #2
Lower the float level a tad. Also check to make sure the vacuum advance is working on the distributor. Crossed plug wires will also cause the popping.
 

Mongo316

New Member
Apr 28, 2004
43
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0
Hamilton ontario
Apr 17, 2006
#3
  • Apr 17, 2006
  • #3
would the lower feul level in the float make it run better? does that mean that too much fuel is getting into the carb due to the floats being to filled? I also noticed that my rotor fits ok but could be tighter.
Any thoughts
Thanks for the replies
Mario
 

Stangninjak

Member
Apr 16, 2004
324
2
19
Apr 17, 2006
#4
  • Apr 17, 2006
  • #4
Check you distributer and makes sure your timming is correct..it could be the vacum to it. I run a 670 on my 351, and the way it comes out the box is dam near spot on. Check you levels with those clear plugs, and set it. If your timming and everything is hooked up correctly, you should have n problems
 

Mongo316

New Member
Apr 28, 2004
43
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0
Hamilton ontario
Apr 19, 2006
#5
  • Apr 19, 2006
  • #5
Hello all here is my upadate so far.
- set the fuel level in the float at proper setting no change still missing.
- let the car run unpluged cyclinder 5 and noticed the car ran the same so i figure cyclinder 5 is missing.
swaped plug wires no difference replaced spark plug no difference.

One thing I noticed is when i did my swap i change my cap and rotor to an acel but the cap does not sit tight in top I have a feeling that this may be the culpret.(any thoughts)

Any one have a part number for a cap and rotor for a 1969 351w with duraspark.

Thanks again for all the help
Mario
 
D

D.Hearne

New Member
Sep 29, 2000
11,730
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south louisiana
Apr 19, 2006
#6
  • Apr 19, 2006
  • #6
69's never had Duraspark, but the caps are interchangeable. You can even refit the old small dist to the large EFI style cap and rotor. The cap adapter, cap and rotor can be bought locally at your parts house. You want an early to mid 80's cap and rotor.
 
8

86bluecobra

Advanced Member
Dec 20, 2004
4,265
12
69
B.C. Canada
Apr 19, 2006
#7
  • Apr 19, 2006
  • #7
anychance the intake valve on number 5 cylinder is sticking?
 
B

bnickel

Founding Member
Aug 21, 2002
5,640
3
77
lubbock, texas
Apr 19, 2006
#8
  • Apr 19, 2006
  • #8
if the floats were set high or sticking you probaly need new plugs all around. i was having the exact same prob on mine, turns out the floats were set a little too high and it was running way rich at idle, mostly because the choke was set way too rich as well. i adjusted the floats and choke and changed the plugs and it runs perfect now. i have a box stock 625 road demon and they are notorious for being rich out of the box anyway. i also drilled the idle air bleeds out a little larger too and that helped as well
 

69Rcode_Mach1

Active Member
Apr 20, 2004
1,473
1
37
Salt Lake City, Utah
Apr 20, 2006
#9
  • Apr 20, 2006
  • #9
Do what D. Hearne said first he knows his holleys. Then I am going to recommend you check the timing. What is initial and check to see if it advances properly. Then if that is all correct and you corrected your floats it is time to tweak with the carb. Could be a lean issue if it is sputtering, there are a lot of possiblities. Accelerator pump may not be big enough, or too big.
 

Mongo316

New Member
Apr 28, 2004
43
0
0
Hamilton ontario
Apr 21, 2006
#10
  • Apr 21, 2006
  • #10
all is working looks like it was spark. replaced the cap with a ford one (fit nice and snug) and bang runs like a dream.

Now to get rid of that black spring for my secondaries switch to yellow or white not sure which one anyone have any thoughts. BTW I am not concered about feul econnmy as it my sunday car.
Cheers and thanks to all
Mario
 
D

D.Hearne

New Member
Sep 29, 2000
11,730
6
0
south louisiana
Apr 21, 2006
#11
  • Apr 21, 2006
  • #11
Go with the lightest one. If you happen to have idle setting problems with that one use the next heaviest. With a too light spring, some engines will pull the secondaries open slightly at idle, making it hard to set the idle.
 

Mongo316

New Member
Apr 28, 2004
43
0
0
Hamilton ontario
Apr 22, 2006
#12
  • Apr 22, 2006
  • #12
Mr. Hearne Canada thanks Lousiana for all your help! can't wait to roast the tire'sc lol at the track of course
Cheers Mario
 
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