IMHO....
First .....do the Tune, downpipes and T-stat (replace plugs with Motorcraft SP534 or equivalent... one heat range cooler and gap your plugs to .030 also)...see the second rec... ALSO...
Second .....Do the 3BAR MAP sensor mod... and have LMS mod the tune for it (mine works GREAT!)... you will then have the MAP you're going to need when you do the turbo upgrade (stock sensor and tuning cannot even sense boost above about 14.5 psi (you stock turbos can generate 16-17psi reliably with the LMS v8 tune... no need to dump it out the wastegate) The ATPs will get you 25psi easy.
You don't need the noisemaker eliminator pipe if you do hotpipes... I would suggest doing the entire hotpipe set... it gets you the eliminator included (it's just the intercooler to throttle-body pipe) and your ready for the increased boost from the ATP turbos when you do it. (I love my hotpipes!). Hot pipes are the charge pipes (hi pressure after turbos, but before TB... no cat is available or needed.... the ceramic has no performance benefit on hotpipes or downpipes (at least when Mike and I tested them all on the dyno using my 'q3 SHO... either PC or ceramic... PC is a lot cheaper! I did ceramic for aesthetics... Mike and I dyno'ed... no difference with ceramic vs bare downpipes.
There is also no proven performance advantage for the choice of BoV OEM vs TIAL)... I have the OEM on my EBPP hotpipes because I didn't want the loose unused OEM rear BoV just secured to something under the engine cover... If you take it of you throw a CEL and DTC immediately (you can clear but it comes right back until you hook up the rear BoV electrical connection. I also wanted my blow-off to work from the ECU rather than having to change springs like the TIAL... This is a personal choice you'll have to make
JimiJak can weigh in here, as he is more familiar than I am on this,.... but likely the cleanside separator is wasted money if your not going to do the catch can.
I'd do the turbo's last personally
Currently no intercooler upgrade is available for the SHO or MKS...
If you live in an emissions state... be sure the third O2 sensor is on when you present for testing or you'll fail readiness due to DTC on emissions system.
Real world test your car with OEM intake and AirAid... many have actually seen decreased performance with K&N or AirAid... 4DR and bamsho for sure... and got the time (.15-.2 in the quarter) back by reinstalling stock. Mike and i dyno'ed my SHO with OEM intake.... and also just an open pip with everything from the saxophone out removed... no difference... it's the saxophone after the filter-box that's the problem... I am having these pipes rebuilt now to see if they make a difference... It may eventually be marketed by a company called MDesigns... I'm not selling.. just know intakes are still an area of development for our cars.
There's a lot more... but those are the salient points for a strong system and not spending XS $
bpd is one of the 4-5 pioneers of methanlo in these cars... his info is excellent
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Here is a list originally posted by 4DR Oct '13 (he had a 600WHP Flex!) It may be of some use to you:
Thought this might be a good topic for new owners to review:
I'm going to rank these by my opinion of best mod by power per dollar spent.
1. Tuning - you can pick up 30-70HP here pretty easily depending on what fuel is available to you and if you want to run race gas or not. Figure around $500 with tuner. The lower octane you can run the lower HP you an pick up thus the range. If you really want to maximize your power with tuning doing a dyno tuning session with your tuner will pick up another 10 to 30HP (IMHO) but will cost you a few hundred dollars more. If you're looking for ever HP safely this is the best case scenario.
2. Meth injection - you can pick up another 30-60 HP here depending on how aggressive you want to get with timing and your tuner. Cost between $200 and $1000 depending on how fancy you want to get with controllers, extra bottles for storage etc.
3. Turbo upgrade - If you have a tune and meth injection (my suggestion) or an aux fueling solution (discussed later) you can upgrade your turbos. Worth another 30-? (most HP now is 600WHP with aux fueling)HP. Currently the upgrades upgrade either your compressor wheel and/or add an aftermarket wastegate. There is also a full turbo upgrade coming this fall or winter so no one knows the true maximum output of the turbo upgrade scenario yet and how much power the block will take. Currently $1500 to $2000 for the two stock turbo upgrades, and $2200 for a true turbo center section upgrade.
4. Downpipes - luckily multiple companies offer these now and they're getting cheaper, between $700ish and $1000 for around 20ish HP and quicker spooling of the turbos.
5. Exhaust - $100ish (remove 3rd cat, resonator and mufflers with straight pipe) to $1000+ for full stainless catback exhausts. Another 20ish HP here.
6. Intake - jury is out on this one, we've seen these drop ET/MPH from doing intakes but hopefully we'll be coming out with a new intake tube per turbo with a cold air or sealed stock style box soon. $200ish to $700
Optionals not normally used (my crazy mad scientist mods)
Nitrous - I've personally ran a 75 shot on my Flex and picked up .6 in the 1/4 mile. You can pick up a used kit and controller on Craigslist pretty cheaply and install. For all brand new gear it can get expensive. $250 (used parts) to $$$$$ for new.
Auxiliary fuel system - I'm the only one who's built one so far, to replicate with what I know now around $2800. Gives the ability for unlimited fuel without the HPFP sagging under load. Needed in the long term for the true turbo upgrade or if you want to run E85. This includes injectors, dual in tank fuel pumps and a modified intake manifold or intake spacer (working on this one)
E85 or E85 mix - Auxiliary fuel system required for this one as the stock system can't handle ANY E85 mix without running out of fuel. E85 let's you increase the timing massively and run "hotter" boost while cooling the intake track off as well. An alternative to running alky/water injection but a true fuel. Requires dual in tank fuel pumps to replace factory pump. This fuel has allowed me to get to 600WHP on just a turbo upgrade and downpipes/cutout.
Exhaust Manifolds - Now that I've hit 600WHP, the small size of the factory exhaust manifolds is starting to get in the way, need to find a way to replace stockers, this might open up a way to also install a T3 turbo swap.
Water to Air Intercooler - 600WHP has caused me to start looking hard at the factory intercooler and replacing it. An aftermarket water to air will be the best scenario as there's just no good way to fit a big air to air in the front of the car. I'm guessing at the current 26PSI I'm at that I can pick up 30-50WHP here.
Dual-in-tank fuel pumps - Auxiliary fuel system required for this one as the stock system can't handle ANY E85 mix without running out of fuel. E85 let's you increase the timing massively and run "hotter" boost while cooling the intake track off as well. An alternative to running alky/water injection but a true fuel.
Cheers!
