Ok so im at the point finally!! I can upgrade and do some serious work to my car. I wanted to know which is a better buy or what is the power difference between a rs6 powered s4 and a k04 powered s4. On jh motorsports it doesnt look like price is that much different between the two but alot of people are saying that you want to upgrade internals to go with rs6's. Would it be a good idea to run rs6's and just dont run them to there full potential and upgrade internals at a later time?

 

thats what im doing right now.. rs6 turbos should get here friday, my 3 inch dps a lil later, 034 track density motor mounts in a few days.. with the rs6's you should get more power and running them at less stress.. what you will get for sure is a little longer turbo lag, but id say more sustained boost thru the upper rpm ranges.. im guessing ill have close to 450 whp and not pushing my turbos too hard.. you can get a good tune for around 1500 for the rs6's and i think the same for the k04's.. you will pay a little more for the turbos .. but i think i made a good choice for not going to build my engine..

 

what is the stock tolerance of the motor internals? I know rule of thumb is 100hp per cylinder but has any one pushed this or proved it? I like the K04 setup just because i hate turbo lag, it sickens me.

 

I know people who have thrown rods out the side of the block with a K04, it's just how aggressive do you want to go? The lag is not that noticeable, in my car with RS6's I'm at full boost around 3900 when i have my full exhaust on and 4100 with the exhaust dump open. What helps with our cars is an X pipe, it equalizes the exhaust gas and helps spool happen sooner. I would say go with the RS6's I love mine, pushin em' on a custom VAST tune to 32PSi with my race tune and it pulls 2.6 FATS when its 60 deg F in a 3900lbs car (its an avant with a subwoofer and I weigh about 200lbs). Though, I have rods, cams, meth, and a few other didies, I wouldn't have gone with different turbo's. If you're really worried about lag have the hot-side wheels modified and include an X pipe in your car and you will be very pleased.

 

whats an x pipe? im getting ready to build mine and im guessing my peak pressure with a stock block will be 26 to 27psi or so...

 

26 and 27 are some pretty big numbers with rs6's and stock internals. If you want that kind of boost I'd do internals.

 

secretly im hoping i DO blow the motor and then my wife will have to agree to letting me build one.. ;-)

 

i mean.. yeah.. i know.. i was just bull shittin'...

 

an X pipe is an equalizer of sorts. it goes on your exhaust after the downpipes.

 

jason at jhm did tell me that running 25 or 26 wouldnt be a problem with stock internals and these turbos.. he also said that occasional 28 psi runs wouldnt be that bad if the temperature was down..