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Help with my FBM

robs347stroker

New Member
Hey all,

Just picked up my first Fox. I'd drop pics but it's saying the file size is too large. 347 stroker, 5 speed, stage 5 clutch, carb, long tube headers, cat delete, short throw shifter, with advertised new pilot bearing, clutch fork, rear main seal, clutch cable, throw out bearing. 5 lug conversion on back with new MT streets and Weld wheels. She's loud, sounds and looks great.

I'm no mechanic, so I depend on local mechanics at $110/hr and a friend who works at a dealership but doesn't know FBM. I have some concerns and don't want to sink a ton of unnecessary money into her right now, but want to do right and make her perform better for next year or the next owner (long term if I keep her I might do carb to EFI swap, turbo or sc, new paint, interior work).


My concerns:

1) I see some fluid under the vehicle and can't determine where it's coming from (I don't see oil spots on driveway, just some fluid thats on the undercarriage)

2) Runs like shit in the cold and on highway

3) Feels slower than it should be

4) Sometimes doesn't start in very cold weather

(I know I shouldn't drive her in winter but just purchased and had to get her inspected, fixed up)


So far I've
-fixed a bunch of electrical problems, rewired brake/hazards/turn signal lights.
-New outer and inner tie rods
-alignment

I'm planning on changing oil, transmission fluid, and go from there. Any help is much appreciated
 

Spaznaut

New Member
I'd say your choke isn't hooked up. I don't drive mine in the cold because it runs like crap. You can check. If you don't know how to check for the choke look for the flap in the primaries up top and see if it is hooked to anything. There are 2 types, mechanical (cable with a pull knob inside the interior), vacuum that will have a hose hooked to a port on the carb usually. You may need to do a tune up since you don't know the history on the motor. Inspect cap, rotor, wires, plugs, fuel filter. Not sure on your fuel pump set-up but you may need to check your pressure. Youtube will be your best friend.
 

broncojunkie

Well-Known Member
The fluid you're seeing could be several things. You might find it when you charge fluids (low level). If not, just use some degreaser and a pressure washer to clean it and then keep an eye on it. You should be able to see where it's coming from. Pay close attention to the steering system, particularly the steering rack and lines. I've never seen one that didn't seep a little fluid here and there.

Your low-power and starting/performance issues in the cold could be related or more than one issue. Start by checking or replacing the plugs (properly gapped), plug wires, cap and rotor. A good tune- up will make a big difference, if they're not up to par. Go ahead and change the fuel filter, too.

Once you're confident all of that is in good order, you'll want to check/adjust timing and properly tune the carb and timing advance. Proper carb adjustment can be done by "seat of the pants", but a much better method is to install a wideband air/fuel guage. You'll have instant feedback from your carb. You can install it easily/temporarily or you can do a permanent install for constant monitoring. Once you get the carb adjusted, you shouldn't really need it (but it's still nice to have).

Another thing you will want to check is what rear end gear ratio you have. While changing fluids, you'll be able to see it marked on the edge of the ring gear or on the end of the pinion gear. Many of these cars came with a tall 2.73:1 ratio, which is great for highway driving and mpg, but don't do much for performance.

You also didn't mention the year (or did I miss it?). I'm curious as to whether this is a later model that has been swapped to carb or an earlier carb model.
 

robs347stroker

New Member
The fluid you're seeing could be several things. You might find it when you charge fluids (low level). If not, just use some degreaser and a pressure washer to clean it and then keep an eye on it. You should be able to see where it's coming from. Pay close attention to the steering system, particularly the steering rack and lines. I've never seen one that didn't seep a little fluid here and there.

Your low-power and starting/performance issues in the cold could be related or more than one issue. Start by checking or replacing the plugs (properly gapped), plug wires, cap and rotor. A good tune- up will make a big difference, if they're not up to par. Go ahead and change the fuel filter, too.

Once you're confident all of that is in good order, you'll want to check/adjust timing and properly tune the carb and timing advance. Proper carb adjustment can be done by "seat of the pants", but a much better method is to install a wideband air/fuel guage. You'll have instant feedback from your carb. You can install it easily/temporarily or you can do a permanent install for constant monitoring. Once you get the carb adjusted, you shouldn't really need it (but it's still nice to have).

Another thing you will want to check is what rear end gear ratio you have. While changing fluids, you'll be able to see it marked on the edge of the ring gear or on the end of the pinion gear. Many of these cars came with a tall 2.73:1 ratio, which is great for highway driving and mpg, but don't do much for performance.

You also didn't mention the year (or did I miss it?). I'm curious as to whether this is a later model that has been swapped to carb or an earlier carb model.
Thanks for that! It's a 1990 GT. To note, I haven't experienced many starting issues when using my method of turning key to aux, wait 2-3 sec and crank it. If it doesn't start immediately I turn key to off, wait 10 sec then hit again without issue it starts.
I think I'll start with a good tune up. I then need to find a good local speed shop that can give her a once over if any problems persist. It's really a fun reliable car for its age!
 
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