this is my first post, but i have been reading everyone elses for a while. I have a 1990 mustang gt 5.0 AOD. I recently decided to do a few simple mods so i no longer have a stock mustang. I have a BBK cold air fenderwall kit, MAC 1 5/8" long tubes, MAC o/r h-pipe, and Flowmaster american thunder 40 series exhaust. Do you think this will actually do anything besides the obvious noise increase? I was also wondering how hard it is to get the long tubes in on the drivers side, I have heard many stories.

 

Welcome to the forums, sounds like you have a plan, the LT's may require lifting the motor to shimmy them in, and yes you will have hp gains (15-20rwhp) but some low end torque losses. Good Luck and keep modding!

 

welcome..but it seems that you didn't read enough the headers will hurt you more than help as your not going to spend much time in the rpm range that they work best, also the BBK kit isn't going to get you maybe 1-4 horse power, not cost effective now the rest of the exhaust IF you went with 2.5" piping is right on track..if you need some REAL help just pm me

 

Sounds like you are off to a good start. You will gain some minor HP by making those changes, but expect to lose a little TQ on the bottom end when you open up the exhaust. You may also want to think about advancing the timing a few degrees for some free HP. Between the CAI, the exhaust, and the timing, you can expect to gain around 30 HP or so.

Edited to add: The above numbers are assuming that you can advance your timing from 10* to 16*.

 

I think you will be happy with the difference

and then you will want to do a HCI swap