Hi Guys,

I am about to get my friend, Sean Cathcart (aka: scathcart) to build me a new engine for my 91 coupe.

what i want is a 4-port with an aggressive streetport or bridgeport, ported intake manifolds, no power steering, A/C or airpump. basically an all-motor nitrous-specific engine.

as i've never seen a dyno sheet of one who has a similar set up, what general hp (bhp) numbers will i be seeing with this type of rebuild?

my realistic goal is to achieve 300hp with a 100hp shot of nitrous. can i do it with this plan?

 

kahren has taken a street ported 6 port (s5 I think) with only a Racing beat header, straight cat replacement pipe and racing beat dual exhaust, haltech ems dyno tuned and attained 195 rwhp. Scathcart seems to really have some similar experience with high performance NA builds, so I don't see any reason why you couldn't get 200 rwhp out of an all-out street port build done by him. A bridge would probably be happier with a new intake manifold rather than using a ported s5 manifold, while the street port could probably live with it more comfortably. Na performance is a dying art, although maxthe7man posted some interesting data in the rotary performance forum about FD engines converted to NA with streetports and exhaust, done by the Japanese tuners due to the high cost of fuel over there. Anyow, he posted results of 250ish rwhp, just search that forum for "six ports, what's possible".