my car revs slow

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Start with pulling codes to see if the puter will give you a clue. For instance a lean code would have me checking vac lines (a vac leak can cause a bog when revving a motor).

Good luck.
 
fp 38 timing 14

Bump the fuel pressure up to 44 take timing down to 12 and get it tuned. Once you have it tuned you can bring more timing into it. What do the plugs look like? If you have fouled out plugs that would be why it is not reving quickly. What kind of head, intake, and headers do you have? If you are restictive there is another reason why you are unable to rev.
 
His fuel pressure is just about right, timing is just about right as well, My suggestion to you would be a custom tune or a tuning device if your the type to want to do it yourself. I do like the idea of checking plugs, reading plugs can tell you alot about what is going on in your motor.
Also just for the sake of ruling it out, disconnect the battery for about 30 min, let the computer reset and relearn, again just to rule it out.

Bump the fuel pressure up to 44 take timing down to 12 and get it tuned. Once you have it tuned you can bring more timing into it. What do the plugs look like? If you have fouled out plugs that would be why it is not reving quickly. What kind of head, intake, and headers do you have? If you are restictive there is another reason why you are unable to rev.
 
His fuel pressure is just about right, timing is just about right as well, My suggestion to you would be a custom tune or a tuning device if your the type to want to do it yourself. I do like the idea of checking plugs, reading plugs can tell you alot about what is going on in your motor.
Also just for the sake of ruling it out, disconnect the battery for about 30 min, let the computer reset and relearn, again just to rule it out.

The timing is right but if he back a couple of degrees out and it runs better then he was to far advance. For fuel pressure I have never ran a mustang lower then 40 and when ever we tune we never tune we always bump it about 40 usually to 44. You have to rember when you have a bigger cam you will need that extra pressure. But again what is the intake, head and header combo. That could be one of the thing hold you back.
 
The timing is right but if he back a couple of degrees out and it runs better then he was to far advance. For fuel pressure I have never ran a mustang lower then 40 and when ever we tune we never tune we always bump it about 40 usually to 44. You have to rember when you have a bigger cam you will need that extra pressure. But again what is the intake, head and header combo. That could be one of the thing hold you back.


But our cars have that thing called "Adaptive Strategy". It will compensate for increases in fuel pressure to get the AFR back to stoich.
 
My fuel pressure is right on 38, I have a much more aggressive cam than the X cam he has, matter of a fact the highest fuel pressure I have seen with a h/c/i 302- 331 is 42psi N/A. If I went to 40 psi on my current setup the car runs like poo poo, under 38 and much the same. If it was boosted maybe I could see it, the computer and tune will compensate for fuel pressure.

I just re read your post porchstang, and you may be right on the fuel pressure without a tune. Sorry for the confusion. He really needs to tune it right, otherwise he is leaving power on the table, and is more than likely his problem.
 
My fuel pressure is right on 38, I have a much more aggressive cam than the X cam he has, matter of a fact the highest fuel pressure I have seen with a h/c/i 302- 331 is 42psi N/A. If I went to 40 psi on my current setup the car runs like poo poo, under 38 and much the same. If it was boosted maybe I could see it, the computer and tune will compensate for fuel pressure.

I just re read your post porchstang, and you may be right on the fuel pressure without a tune. Sorry for the confusion. He really needs to tune it right, otherwise he is leaving power on the table, and is more than likely his problem.

Thats what I meant was with out a tune bump it up and take some timing out of it and see what happens you can always put it back to were you had it. Like I said before what do the plugs look like, and what is the head, intake, and hearder combo? These are three very critical parts.