I was hoping some one can help me figure out how much hp i have, here are my mods on my 87gxl with 94,000 mi:

bonez superflo cat
2.5" pipes all way thru
dynomax hi flow mufflers
k&n air filter

it's not much right now, but i would like to know how much hp i'm playing with at this point before i decide on some other mods, like pulleys, and header...

 

Go find a dyno and test it... there is no accurate way to tell you how much power you are making, especially with 90k+ miles on the clock. You could be making stock power, less than stock power, or slightly more than stock power. In a best case scenario I would say that your setup is good for about 5hp over stock at the wheels... So that would put you at about 115-120 rwhp.

For a selection of dyno pulls and mods on different cars check out http://www.trackracers.org/matt/dyno.html

-Matt
'88 GTU
'87 TII

 

"5hp over stock"

i disagree i would say more like 155hp at the fly wheel
146hp is stock and with exhuast and filter u got 10hp gain min..