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Discussion Starter · #1 ·
My friend has a '68 Mustang with the 302 and 4bbl card,long tube headers,duals,and 3.00 gears.He was trying to run my '88 T-Bird and he couldn't get the car to go past 80.It takes all the car has just to spin a tire.I'm guessing it's in the induction (carb mostly).Any ideas from you carb guys.I'm all about fuel injection.
 

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Does it still have points? Could be bad or out of adjustment. Timing etc. Did it just start doing this? Could be a choke stuck on. Any black smoke? Just a few things to ponder Stu
 

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Discussion Starter · #3 ·
The car was upgraded to the Pertronics for the distributor.No more points.I'll ask him about the black smoke,and have him check the choke.I wondered if it may be the accelerator pump.I'm open to anything.Thanks for the help,I'll pass it along.
 

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could be the timing isnt advancing
 

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Things to check:
with the engine off:
check to make sure that pressing the gas pedal to the floor opens the carb completely - if it have vacuum secondaries just check the primaries.

make sure that if the distributor has a dual vacuum diaphram that only the rear vacuum hose is connected.


With the engine running:
Check the total advance (with the vacuum advance off and plugged) it should be between 30 and 34 degrees for a small block

check to make sure the brake return spring is returning the pedal

Check that the clutch or automatic transmission is not slipping

Check the converter stall speed is correct - too low means a damaged stator and you will get sluggish acceleration and slower than normal top speeds.

Check to see if the exhaust is plugged - a collapsed or rusted double wall pipe can close the exhaust almost completely - so can a plugged catylitic converter and a broken muffler.

Of all these the two most common are the carb not opening all the way and a plugged exhaust pipe. I would check them first and in that order.
Paul
 

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HI
I have hear of people haveing a prob with the Pertronics ignitions might check that.
tim
 

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My "guesses"

Tranny is slipping.
Brakes are dragging.
Timing is not advancing.
Fuel pump is worn and straving the carb.
Fuel filter is full of junk straving the carb.

Like you I'm better with EFI. I take my carbs to someone else. But these are all things that have happened to me that cause the problem you are describing.
 

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It wouldn't be carb unless its not opening all the way or the float is not set right and its running out of gas (not enough fuel in the float bowl).
tim
 

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im curious too what could cause this, i could go 100 but it might blow the block, and i have 2.73 rear, sometimes i think its the tranny or the rear end slipping. but its hard to notice. i have a 2bbl on a roller 302. i also think it could be advance. i need more tools! 65-70 is as far as the power it gives, and the old block used to go 100 easy long ago but then wouldnt, so i dont think it is the engine. must be carb, ignition, tranny or rear.
 

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We need a better description of the problem..Is the car missing at top speed??Does the engine run strong everywhere else?Does it start good and rev good in neutral?..Is the engine revving high like the trans is slipping?
 

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runs fine in nuetral and at speed, just not enough power to go 90-100. no high revs, no slipping that i can tell, but it maybe in the rear...i seem to think it is engine
 

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There is no way I know of that the rear end can slip unless the gears are broken and it would do that at any speed so I don't think thats your problem....I would take a look at the fuel filter.If that is clear then maybe the fuel pump is weak...I used to test this by finding a stretch or road where you can hold it to the floor and see what happens.If its the fuel pump it will eventually slow to a crawl or might even die completely..I have seen a plugged exhaust do this but that is very rare.....I had the exact same condition as you and it turned out to be a siezed up heat riser valve basically blocking the exhaust off at one manifold..You say you have headers so I guess that doesn't apply...If all the rest of the stuff checks out you could try timing or make sure the secondaries are opening on the carb..Next I would do a compression test and see how healthy the engine is...
 

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I'm thinking timming
Disconect advance hose/ plug it and check timming
tim
 

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Did you check the exhaust yet? If you don't know how to check it, here it is:
Connect a vacuum guage to the intake manifold - any port will do.
Use a long enough hose that you can watch it while you drive. As you accelerate look at the vacuum guage - is it steadily dropping - when you cruise does it come back up to between 17 and 21 inches? If it stays low then go back home. Put it in park or neutral and start reving it up slowly. 1200, 1500, 2000, 2500, 3000.... is the vacuum guage dropping ? or is it staying at between 17 to 21 inches? If it is staying low then you have a plugged exhaust.
 
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