yellow351mustang

First I would like to say thank you for all who replied, you guys are great and I love this forum. Have been browsing around this forum and have learned a lot. Yeah, I knew the 2.73 gears would through up a red flag with most, but I agree with Dimebag though, I too feel like it should still pull hard with those gears, even though it would never win a race against another 5.0 with shorter gears. I agree with Nitrous_bob too. I think there is something going on and when I read that post, I slapped my forehead and remembered that the guy I bought the car from had previously changed the plugs and the cap and rotor and it occurred to him that while he was changing the plugs, he should have changed the wires. Later he went out and bought a set of FRPP 9MM plug wires, but never got a chance to put them in. He gave me the unopened box when I bought the car but when I got it back to my garage, I through them onto a shelf and then completely forgot about them. I did make an assumption that since the plugs looked good and knowing the cap and rotor was new, it didn’t even occur to me that the rest of the ignition should be looked at. I did check the timing and was set for 10* and I bumped it to 12*. I do run 87 just because of the cost, but at 12*, I’m still not getting any ping. First thing this spring (living in the northeast, it is 10* outside and not much warmer in the garage, so the car is just sitting under a cover and I have no desire to work on it right now – LOL) I’ll take another look and the ignition. Maybe the plug wires are really old and are breaking down above 3000. I never gave the ignition a second thought because the motor always runs really smooth from idle to even past 3K where the flatness comes to play, it never skips or runs rough. Maybe I’ll change the coil as well. Thanks for jogging my memory. I’ll take another look at the TPS as per Nitrous_bob’s suggestion as well. I know the previous owner said he set it for .99V, I should check it again. I didn’t think of the fuel filter either, I will definitely look into that. I know the car sat a lot. The previous owner had the car for nearly 12 years and never put more than a few hundred miles on it each year. It was pretty much a sunny weekend car for him so I’ll bet all that sitting may have developed some issues. That is why the Mac Flowpath Catback went in as it still had the original exhaust that rotted from the inside out. Another forehead slapper. I remember after reading an article a few years ago in a magazine, I checked the throttle plates on my ’69 and found that when the go pedal was pressed against the carpet, the throttle plates were not fully opening wide. They were only open about 80%. Maybe because the cable stretched some, but I had to shim the petal, which brought it away from the floor a little and was able to get wide-open when the pedal hit the carpet. I’ll check this on the throttle body plate as well. I should check the TPS at WOT as well. I’ll let you guys know how that turns out. I also liked what you said about the gears as well. My only interest in keeping the 2.73, was the gas mileage, but was very interested in what you had to say about the 4.10’s. I would love to swap the gears and go with something more aggressive, don’t know if I would go that high, but would love to go to something like 3.27’s or 3.55’s. Thanx 93 LX FiveO for your input too. I was wondering about the stock cat’s and H. Even though it has the 2.5” Mac’s, I know that the four Cat’s and stock 2.25” pipe and stock headers were restrictive. I didn’t know how much of an effect it would have to upgrade those, but was very interested in what you said about your experience. I have to run some Cat’s here in MA in order to pass emissions, so off-road pipes are out, but I know that MAC makes a 2.5” replacement H with two Cat’s that are much less restrictive (still on the fence about the X-pipes, I’m old school and love the sound the H makes much better even though technically they may not flow as good). And I would love to upgrade the stock headers. Thanx for your input on that. I guess once I check to make sure all is OK under the hood, my goals are better gears and then attack the rest of the exhaust. Thanks for all for all or your inputs. OK sorry for the novel.