I purchased an '08 GT California Special this past year and recently had it dyno'd at 263HP at the rear, 278 max torque before upgrading the exhaust with JBA titanium ceramic shorties and Borla Stinger S-Types (axle-back).

There was an article in the February 5.0 Mustang issue about adding naturally aspirated power with heads, cams, and intake for three-valve engines in '05-'10 GTs. I've been on the fence about messing with various engine components versus doing a straight up supercharger like the Edelbrock E-Force. I know I can make superior power numbers going the forced induction route, but it's tempting to take on the smaller incremental mods from a budget perspective. However, I keep seeing adds from Ford Racing saying "up to 50+ HP" gains with either their new 4.6L 3V intake or even their hot rod cams. Based on those numbers, I'm estimating those two mods plus a CAI and tune on top of my new exhaust set-up would help me push 450HP, estimating 391HP at the rear. Clearly my numbers are wrong as I'm estimating over 20HP more than the '08 GT featured in the article which also had upgraded cylinder heads, long-tube headers and a bigger throttle-body.

Can anyone tell me what I'm doing wrong in my effort to estimate reasonable power gains?

And most importantly, if I do end up going with the FRPP cams and intake, plus adding a CAI (leaning Steeda) all with the appropriate tune for a daily driver during the warm months, what should I expect in terms of real power gains?

Thanks for your help!

 

Right off the bat, I'd say your problem is assuming you'll gain the bullchit #'s that are advertised. There's no way you'll get much beyond 350 RWHP without some significant internal mods and even then you'll be spending more than what a SC will cost, plus lose reliability. Cams, heads, intake, LT's, UDP's, weight loss a few others and MAYBE you'll push 350 RWHP. Shorties give minimal gains and exhaust work beyond the H-pipe yields ZERO gain; possibly low single digits but you can't even make it out from typical dyno variance.

 

with the hotrod cams, FRPP intake, and CAI.
you're looking at 350-ish rwhp.

you can never count on an advertised HP rating. when doing this, I usually cut the advertised HP in half and that's the real world HP rating.
but people with those same cams and CAI and LT's are about 330+ rwhp. so adding the intake you might make 10 or so more hp.
but i really dont like guesstimating hp. i like to rely on the good ole dyno to prove it.

330-350 rwhp is pretty darn good for some mild mods

 

The key words your missing is "UP TO" 50hp gains which in reality the add should say " With a stroked engine, CNC ported cylinder heads and cam shafts custom ground for the short 9" runners you can gain 50HP" Same goes for any and all power gains from all manufacturers.

 

advertising is just manipulation to get into your wallet. Atleast you checked on the boards before you went to far. I had honestly thought about staying NA it took me a couple of years to decide to go the FI direction and im glad i did. I was worried about reliability but my car runs fine. The NA setup is expensive and most of your power gains are much further into the rpm range than say a twin screw. Even after heads and all that your rpm range for peak power is alot. I would tell u to get a Supercharger. And if u do make that choice of FI route dont get the supercharger that is inexpensive. Research the different variations and then make ur decision based off those calculations

 

Thanks all. Supercharger it is!