For a FI aplication, over 10 or 12 psi, does having ported heads make a big difference over stock ones? HP difference (if any)? or time wise at the track ? Or just not worth buying them ?

 

10psi is what a lot of persons around here consider the limit of the "safe zone" of our engines with stock internals, going over 10psi is just pushing the envelope, and you have to consider something to my friend, mexican gas quality sucks big time so becareful!

 

I know about the 10 psi might be the safe limit for the engine, but thats not the post question. And about the gas, its gas from the USA most of it, we sell the oil and buy back gas, u should know that, so if i´m using sucky gas, so do you[&:]

 

not really, I use 100 octane fuel in my car and yes, it does make a difference using ported heads, your engine will be able to handle more boost, wich increases HP, common sense.

 

ported heads = more airflow

s/c = more air into the engine

so of course it will be better!

 

Whoever answers from SHM told me I would see 0.1 sec at most as a gain , thats why I´m asking guys here

 

Yes they would help.
But if you don't have a built short block there is really no sense in buying them.
You can just add a smaller pullies to get you to the stockshort blocklimit.