prior vehicle would pick up speed with a quickness, now that i install the flowmaster exhaust system. it doesnt pick up speed as quick. Is this normal? What could i do for it to pick up speed with a quickness?
It wont effect the mpg , How hard you ride it will
No, it won't. It actually will help fuel economy, but just a little.
A lot of people have that problem. You lost your low end torque but gain top end torque. It all depends on what you want. If you want high end torque for cruising on the highway then leave the exhaust on. If you want low end grunt for pulling trailers or quick acceleration from a stop then take off the aftermarket exhaust and put the stock one back on.
Your exhaust is no longer under the 5/70 power train warrenty. So it don't matter what you put on it. It will not void your power train warrenty because your not modifeing the engine. If it was mine I'd go with headers and cat back duel. You'll pick up about 30 HP and get another 5 miles to the gallon of gas.
evo and bogey are both right. In changing your exhaust you have lost low end torque due to a less restrictive airflow ( less back pressure) but as stated the increased airflow will give you more power in mid to upper rpm ranges. An engine is basically a big air pump so if you're getting the exhaust out quick you should also get air into the engine quicker. Maybe try an aftermarket cold air intake. Will work better than the stock intake which are usually very restrictive. If you want to spend a few hundred $$ you could also invest in a programmer like Hypertech or Superchips. They let you change settings in your vehicles computer and gain a decent amount of performance. I have a dodge ram with a 360 and have done the same with some good hp gain. (seat of the pants dyno). Best thing i did though was swap the 3.55 gears(which are good for nothing but highway cruising) for some 3.92s. much better acceleration. just some ideas for ya ps. if you want to go quickerjust floor it. :)
