The main difference really is the looks. The GT40 upper 'might' flow a little better than the cobra upper but nothing you'll notice. The RPM would be a good choice for your goals. You'll do over 400 with a s/c fyi.
I've seen an upper Cobra intake for $150, i contacted the seller about it, what do you think about this?, More of less about how much would a good porting job go for for this intake?, and more importantly would it outflow an out of the box RPM if the Cobra was ported? thanks
$150 for the upper + the lower + porting + gaskets and the RPM is still cheaper and better for the application. I'd be more conserned with a cam choice rather than an intake choice. What you should do is try and get a 'carb' sticker for an E cam but use a good custom grind cam and lie to the inspector and say its an E cam Do you know anyone that can do "under the table" inspections?
$150 for the upper + the lower + porting + gaskets and the RPM is still cheaper and better for the application. I'd be more conserned with a cam choice rather than an intake choice. What you should do is try and get a 'carb' sticker for an E cam but use a good custom grind cam and lie to the inspector and say its an E cam Do you know anyone that can do "under the table" inspections?
the $150 was for both upper and lower, now more or less how much would the porting be?, and again more importantly would a ported Cobra flow the same or better than the RPM?, ideally i'd like to keep it as "Ford" as I can and if it ends up being more or less the same price but i can have an equally/better flowing "Ford" intake i'd take that instead. I know ultimately the RPM would outflow the Cobra intake but again, i'm not looking for 500+ HP, so it wouldnt really matter with this motor. As far as a cam, I do know an "under the table" inspector/smog tech , it'd be nice if I could get it to pass emissions but it doesnt HAVE to.
The RPM will crush the cobra on this given set up your planning. I know your not planning 500hp, thats why I didnt recommend a ported victor and afr 225's To port the lower cobra is gonna cost about $150. But your making it harder and harder to acheive your goals. Just spend a little extra and use an RPM or even consider a trickflow track heat which is about $100 less than an RPM. Stick a 75mm tb on it as well.
because it'd be NA for a while and I feel i'd get a bit more HP out of the 347 than the 306. I know the 347 stroker would be a bit more due to me having to get the crank and rods, but i'd want to get forged rods too so i might as well spend a couple hundred more and increase displacement 41CI by going with the stroker.