Have a 5-speed 87GT with some mods.. Mostly bolt on with full exhaust, MSD igniton and 3:73 gears posi.. I am curious what the highest shot of NOS the stock motor can withstand? And what will the biggest shot the stock can with stand get me in the 1/4 mile?
I am going to be runing a 125 shot wet kit on my stocker, It should be totally safe because of it being a wet kit. Go with a wet kit that injects fuel with the nos so your engine does not get a lean mixture and blow up. I am going to get a bigger fuel pump and some colder running plugs before I run it. 125 is the most I would go on a stock engine, I have seen a 150 shot on a stocker and it did not work as well as the 125 shot, I would stay between 75 - 125 shot.
I had a NOS 05115 dry kit with a 100 shot and went from 14.08 @ 98mph to 12.78 @ 109. You should get better times b/c my car is heavier. Here is the Dyno
I had 129K on the car when I installed it and went through 2 15lb bottles a week just spraying everywhere all the time. I added an S-Trim at 148K and I am now over 160K with all stock internals, heads, cam, and bottom. It's a great motor the 5.0 and the only way to hurt is doing something dumb. You will be fine anything under 150 shot.
I have the nitrous works 125 efi wet kit. I dont think you can make a efficient wet kit by yourself unless your some kind of metal fabricator. I like this kit because it uses a plate that goes between the throttle body and the intake that has 2 small pipes spraying nitrous and fuel at the right amount. I have the switch that activates it when full throttle, Thats seems to be the best way in my eyes. Nitrous works has great kits that are built right and will hold up for years.