i was wondering if i will gain 40 hp with all these mods.the mods are a iroc y pipe and intermediet pipe a hooker aerochamber muffler with 3" exhaust tips a ASP underdrive pulley set a hypertech chip and 160* thermostat

 

don't think you'll get 40hp from those, normally for big hp gains you'll have to go internal, good cam, larger injectors, basically a stronger motor. but that's just my take on it.

 

I am doubting it

you will prolly get something like 15-25

but that is just my guess

 

I think you would get 15-20 HP max. If you want 40 you'll need cam, headers, intake, roller rockers etc.

 

looks to me from his sig that most of the internal stuff has been done already. if so, i would see those mods giving him much more than average gains. i would have to say 30, and 40 isn't unreasonable. once you do the above mods, they work along with you other mods as well.....keep us updated