this would be on my stock bottom end 4.3L blazer

@ the moment im running 10psi and running very good. but beyond 90mph the truck falls on its face. i was thinking about spraying a 50shot of nitrous in the top of second and through third.

there are guys on s10forum running 8psi + a 75shot of spray on my motor with bone stock internals.

its either that or add 2 or 3 more psi. im not sure what i want to do i was hoping yall could give me some insite as to what you would do.

 

Any idea why its falling on its face? Are the IAT's getting too high and timing is being pulled? The 50 shot might help that out but, if youre gonna do it, might as well spray from the beggining

I do think that 10psi and a 50 shot is a lot to ask of stock pistons. I'm sure it will hold for a while but not forever.

 

i dont ask of it to hold for ever since im gonna start collecting parts for a forged bottom end soon. its going WAY rich in third gear like 10:1 or richer.... im gonna be getting hptuners soon to help tune that out. also i was thinking about 12 or 13psi + methanol...... that might help topend and a bigger a/r on the turbine side to help flow...... once it hits 90 to 100mph it starts getting slower.

 

I think your better off getting tuning software and getting your tune inline. It should be at the top of your list for your next mod. With FI it's your most important tool. Getting you A/F up in the mid 11's and playing with the timing could get you the 50 or so HP your looking for. Nothing beats a good tune

 

If you are insistent on using nitrous, start with a small shot, and button up that tune.
You thought about water\methanol?