I have, and am soon to be installing a full exhaust (RB collected header, Bonez Hi-flo cat, and Rotary Performance Cat Back). My 5th and 6th port actuators work (i think they still do) and I am going to install Pineapple Racing sleeves, and lastly I will be match porting my uim and lim. Now truthfully how much REAL gain am I going to realize by installing this on an S5 N/A that has 160K original? I am in no need of a rebuild yet because I have no smoking, mis-idling, or low power issues as of right now. Everything is bone stock. I acquired this car from a coworker who never drove it past 3500 rpm. So you can imagine how much carbon deposits were ejected when I drove it for the first time (my indication that the secondaries were working). The cost? Free-hundred even. Just let her drive it once after I do all of my mods. Keep in mind that this is my third FC. I have owned an 86 (all stock), and then a 91 w/ an RB header and HKS catback on the 91. This particular FC project is a GTU. I am looking for knowledgeable feedback here folks. Thanks.

 

you will get a very noticable gain,RB quots a 28% increase of hp with there ehxuast system( no joke) . if yours flows as well as theres id expect similar gains.

id expect you to make around 195 flywheel hp

 

what about the pineapple sleeves and match ported intake manifolds?

 

the gain in that will be noticabel but not much.

 

Dyno the the power before and after you port your intake that way I dont have to and can just mark it off of my list of things that provide no extra power/cheap mods.

 

Im guessing 5-15HP depending on engine condition. Get a SAFC and then dyno tune it. The tune will be where you realize the most gains .

 

I played around with the engine a little today. Noticed my 5th and 6th port actuators move (with slight difficulty), but snap right back when released by hand. I am guessing that they do not actuate unless under load, so I cant do an actual "Real World" test yet. I am also thinking that I will forego the Uim and Lim porting and just install the exhaust system and then get it smogged so I can drive it legally.
Also, I assume SAFC means Stand Alone Fuel Controller? Or something like that? Which do you recommend? And how much do they generally cost?

 

SAFC = Super air flow converter by Apexi. I recommended it because it's easy to tune, install, and something most tuners are familiar with. A megasquirt would be the best, but of course that requires a little more knowledge of tuning (since it controls ignition).

I'de also recommend a dyno tune or if you can't afford that, go for a wideband.

http://www.spooledmotorsports.com/apexi_safc.html