1973 Ford Mustang

1973 FORD MUSTANG

SIDEWALKLIFTER

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Engine Performance problem
1973 Ford Mustang V8 Two Wheel Drive Automatic REBLT miles

WE JUST REBUILT THIS ENGINE AND IT STARTS BUT RUNS ROUGH AND WILL NOT IDLE EVEN AT 2500 RPM
IT DOES NOT HAVE ANY LIFTER NOISE BUT SOUND LIKE ITS STRUGGLING TO RUN.
THE HEADERS ON THE PASSENGER SIDE GET EXTREMLY HOT ALMOST INSTANTLY BUT THE HEADERS ON THE DRIVERS SIDE YOU CAN PUT YOUR HAND ON EVEN THOUGH THEY ARE VERY WARM BUT NOT HOT.
WE DONT HEAR ANY OBIVIOUS VACUME LEAKS AND ADJUSTING THE SPARK ADVANCE DOES NOT CHANGE THE SOUND OF THE ENGINE VERY MUCH OR HELPS MUCH
HELP SOMEONE PLEASE
WENDELL

Oct 25, 2008 at 5:04 AM

DOCFIXIT

✓Experienced Mechanic
18,828 POSTS

Has carb been tuned/balanced? the hot header is an indication of a very lean condition. Is engine all stock?
Cam ? intake manifold? carb? compression ratio?

Oct 25, 2008 at 5:12 AM

SIDEWALKLIFTER

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the engine was built by smeding preformance in calif and every thing was tuned,balanced etc when we started having a slight over heating problem and found out thru the sniff test that there was a trace of carbon monixide in the radiator so we replaced the head gasgets,had the heads surfaced and on start up we get this problem

Oct 25, 2008 at 5:20 AM

SIDEWALKLIFTER

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7 POSTS

9.7 to 1 compression ratio3.400 stroke balanced for 28 oz weight 650 cfm,preformance rpm air gap manifold1

Oct 25, 2008 at 5:24 AM

DOCFIXIT

✓Experienced Mechanic
18,828 POSTS

Take some carb cleaner spray around the intake to head and base of carb. If idle goes up thaty spot has a vacuum leak.
Let me know

Oct 25, 2008 at 5:29 AM

SIDEWALKLIFTER

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there is a vacume leak on the drivers side in the middle of the intake,we have it off now and will let you know when we put it back if that solved the problem but it should

Oct 25, 2008 at 6:46 AM

SIDEWALKLIFTER

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the leak was the intake gasget,problem solved and thank you
one follow up question though,what is the best way to set the haudralic valve lash?
thanks
wendell

Oct 27, 2008 at 4:22 AM

DOCFIXIT

✓Experienced Mechanic
18,828 POSTS

If my old memory is correct Ford valve lash is not adj. You just torque each rocker to proper ft lb If head vwas shaved 10 ths or less should not be problem. Did you install a different type of fulcrum and seat?

Oct 27, 2008 at 8:26 AM

SIDEWALKLIFTER

MEMBER
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alum heads with202"/1.60 stainless steel valves
60 cc chambers 170cc port
hydraulic roller
493" intake/ 510 exaust lift
212 intake/222 exaust duration@50"
112 lobe center
1.6:1 ratio full roller

i hope this helps

Oct 29, 2008 at 3:00 AM

DOCFIXIT

✓Experienced Mechanic
18,828 POSTS

Rocker arms should have an adjustment then. Is there a nut with an allen screw in middle over the valve? If so bring each cylinder to TDC then while twirling push rod tighten until there is resistance to turning rod. Then go 1/2 turn further in. Or you can run it valve cover off and adj. but real messy unless you have oli clips.

Oct 30, 2008 at 7:13 AM

SIDEWALKLIFTER