5.0 302
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5.0 302
I have a 91 5.0 302 in a 150xlt. Engine has some miles on it but was taken good care of, all stock, and has a brand new tranny. But I just dont have any power during acceleration unless you put the gas to the floor then it kicks into passing gear. Just all around sluggish behavior. I have tried the fuel system cleaners but with no luck. Could I advance the timing a little to see if I gain power? I was also thinking of removing the cat from the exhaust system because I know that has to be clogged up. If any body has anything On this subject please post. Your help is greatly appreciated.
Thanks
James
Thanks
James
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From: Ottawa, Ontario
The performance of the vehicle depends heavily on the axle gearing. Check your drivers door pillar decal for the axle code and then compare it to this list.. Ford Axle Code Chart .: Articles
Anything less than 3.55 with the stock tires will be sluggish, so consider upgrading this if necessary. The '91 motor was not as powerful as later versions, but there are some things you can do to improve it. Advancing the timing is one of them, try a couple degrees extra and then drive it in various conditions and listen for pinging, if you hear some you need to back the timing off or use a higher grade fuel. The exhaust system is also fairly restrictive on these trucks so anything you can do to open it up will help.
Anything less than 3.55 with the stock tires will be sluggish, so consider upgrading this if necessary. The '91 motor was not as powerful as later versions, but there are some things you can do to improve it. Advancing the timing is one of them, try a couple degrees extra and then drive it in various conditions and listen for pinging, if you hear some you need to back the timing off or use a higher grade fuel. The exhaust system is also fairly restrictive on these trucks so anything you can do to open it up will help.
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3.73 is a better ratio with the 5.0 IMO, but be aware you have to change both front an back diffs if you have a 4x4. Overall this won't make a hugh difference if you have stock tires, so maybe you need to look at some other things first. You said you know the cat has to be clogged up, why is this?
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3.73 were just one that I was looking at. Not sure of the best ratio to go with, Its only two wheel drive so Ill only have to worry about the back. I just want to keep decent MPG. The cat has to be clogged its the original exhaust and at the tail pipe the pressure is quite low. Im not sure exactly what the problem is but I have a few ideas and with your help I think I can get past them.
Thanks
Thanks
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OK.. that's interesting. If you don't get much air out the tailpipe and/or it sounds like air escaping from a tire when the motor is reved, then you have an obstruction, and it's most likely the cat. If the exhaust has been rattly for some time that's a sure sign the cat has disintegrated and parts of it are now blocking the exhaust. You'll want to cut the exhaust open and clear out the debris.
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Cutting the cat off is my next task, I am going to do this weekend hopefully!
I am going to try and build up another motor for the truck but it is in the beginning stages so far! I appreciate the advice and anymore you can add will help.
Thanks
I am going to try and build up another motor for the truck but it is in the beginning stages so far! I appreciate the advice and anymore you can add will help.
Thanks
