Ok so need help to see what the next mod I should do to my 96 GT I added a 4” cold air intake. Unfortunately its automatic but I fixed that problem by getting a shift kit. Next week I’m getting racing spark plugs and the mechanic who is putting them in said I would get 40 HP. So now I’m trying to see what I should do next. So any suggestions would help allot. And yes I try to get headers but I live in cali. So I cant get them.

 

40 HP from spark plugs? not gonna happen.

 

so what do you sugest?

 

What magical spark plugs are you going to use?

Unless you do a power adder or swap those heads out to PI heads found on the newer 99-04 mustangs your car will always be underpowered. The heads hold back alot of power. My advice would be to either get a power adder like nitrous, blowers, turbo whatever you like or do a head swap and cams to actully make it faster.

 

dont take your car back to your "mechanic"

 

lol..if only hp was that simple(sigh)..but yea, save your money and buy a power adder like a blower or nitrous, its the best way.

 

The heads don't hold back the power, it's the intake and cams.
Yes the non-pi(pre-'98heads) could use a lttle work, but mostly the intake and cams in the pre-'98 Modulars is what holds them back.
By switching to the PI heads, matching PI intake, and swapping the cams out for PI cams will net you some really good gains. Your compression will get a good bump to, this is the biggest gain from the PI swap as the heads have a 42cc chamber compared to the NON-PI's 51cc.