Yeah, that was my first post on this website, but don't mistake me for a noob. Blown98GT, I have been working on these engines (4.6/5.4 2V/4V) for over 12 years, your PI swap and four built motors isn't even a blip on the radar, no disrespect. Every thing I said was correct, just don't take it out of context.
The price on trick flow's heads and cams I gave is straight out of SUMMIT Racing's catalog....they happen to own Trick Flow FYI.
I never said you lose mpg with a blower. I said you gain MPG by changing to the Trick Flow heads, I have Fox Lake ported SVO's and when I was NA I was getting 32mpg highway through a five speed and 3.27's. When I first put my Paxton on I went to 27mpg because i richened up and went real conservative. Now I get 30mpg through a D&D viper spec with 4.10's and a paxton on a 2.75" blower pulley. While my SVO's flow slightly better than stock Trick Flows, you will definitely see a nice gain in MPG due to the increase in compression and the reduced pumping losses. Gas prices are going north of $3 again. You may get a decent return on your investment eventually. A well tuned trick flow setup will get probably at least 28mpg, what do you think a stock NPI with a blower will get?
When I said $3500 for a bare bones blower I was speaking of new base kits, not a tuner kit. Obviously a used system will be less, but a used blower has a history that you have no clue of except what the seller decides to tell you - buyer beware. As far as making more power, sure you can add a bigger pulley and make more boost, goes without saying. But I was speaking of the stock kits the blower companies have, and all of the non-intercooled NPI kits will be 6-8 psi unless you order a different pulley. At 6-8 psi, those stock kits for a NPI system will give you, wait for it....... OOOO! 290-310 rwhp. Thats less than the OP would get with the setup I recommended. If he wants to dial up the boost on that setup, new tune, more fuel components....more money. Remember the OP is stock NPI. As for being stuck at 350hp with the H/C/I setup, as I said, add a supercharger if you want more power than that. If he did it in reverse and wanted to eventually make more power than a pulley could provide (450 rwhp on stock NPI is pushing it), he would have to uninstall everything to build the upper motor at that point. Kind of a bit of a waste don't you think?
As for the built shortblock, its insurance. Stock rods and pistons are great at stock power and rpm's under normal conditions. The rods under ideal conditions will hold up for some decent power. But what happens with a bad tank of gas, a NA setup will run like crap. You get into boost at high RPM in FI setup with bad gas.....good luck. Do you need it at 350hp levels, probably no. Will you wish you had gotten one when something bad happens?......This isn't a cheap hobby and you better be prepared and willing to pony up to get things done right the first time, or fix them when they go wrong.
As to the compression bump needing a tune and higher octane, yeah that's true. But with these cars you can screw up the tune by changing the air intake with a CAI...so what's your point? I included the need for a tune in my original post. You should re-do your tune ANYTIME you do something SIGNIFICANT to change airflow or combustion characteristics. On a FI setup, you should be running high octane anyway and you HAVE to get a tune, although the manufactures usually supply a canned tune.
As for cams, just about all performance NA cams will add even more power on a FI motor. As long as you don't overdo it on valve overlap so you don't blow part of your charge out the exhaust you will see gains. I have Comp 270's and have had them NA and now FI. The idea that you can't use an NA cam on a FI setup is silly. You definitely reach a point of diminishing returns when you get really radical with the overlap, but the stage 2 trick flow cam is nowhere near and will still be a power contributor going from NA to FI.
As for people being able to do an install, the idea that your regular joe who wants a faster car having "general mechanical knowledge" is a stretch. I watch NCIS, that doesn't mean I should moonlight as a forensic investigator. You would be surprised just how many people with performance cars couldn't change a throttlebody without screwing it up with or without instructions, let alone installing a blower and an in-tank pump. You wouldn't believe some of the screwed up systems I have seen. Who is to say that that the OP wouldn't consider it a poor use of his time to do the install himself during his free time vice paying a shop to do it and stand behind their work (I'm not talking about a warranty, but if they screw something up they usually like to protect their reputation). Most shops these days charge a flat rate for a blower install plus tune. BTW, in just about all cases, if you order your parts from a shop and then have them install and tune your car, they will almost always give you a deal on some part of the project. You may have to ask, but there you go. Even if the OP installed the supercharger system correctly, going with a manufactures canned tune will definitely cost you MPG. Most canned tunes are VERY conservative. So, eventually, to the dyno they will go and they will charge you full price for sure.
I never said that that NA was a better performace to dollar ratio. The original poster asked how to get to 350hp. I simply am trying to give him a different perspective. The combination I recommended is less than the price of a new bare supercharger kit + install and will give better MPG and power than the base kit.
Personally, I like both NA and FI modifications, and a combination of modifications from both camps gives even more power.
