Ha, I was about to reply in the comments   So here goes:

The only turbo kit that looks reasonable is the PTuning kit.  Throw in their oil cooler kit and cold air box, and it’s roughly $8500-$9000 after taxes.  Even then, I bet the oil temps are still pushing 270F+ in warmer weather which is too high for endurance work.  It’s okay for sprints, like 30 minute track sessions, but you just have to change the oil often and it will still reduce the life of the bearings.  Even then, I wouldn’t trust that manifold to not crack.  Forget about the Greddy kit, that manifold cracks just driving around on the street.  I helped a race team with their turbo kit (in preparation for the 25 hours of Thunderhill) and the only material that they could get to fabricate a manifold quickly was 304 stainless which pretty much what everyone makes their manifolds out of.  Though it was a simple log with extra beefiness, it eventually cracked after about 30 hours of use or so.  That included a 12 enduro test along with a few 3 hour races.  The replacement did last long enough to survive the 25 hours race.

So assuming the engine is good to go, the tranny and diff are definite weak points.  The auto-x guys are near stock power and generally bring a spare rear diff to Nationals competition because they tend to grenade when launching off the line with slicks.  Any turbo S2000 guy that drag races always has a spare diff ready to go to as it’s not a matter of if, but when even on street tires.  The Puddymod diff seems to be pretty strong and holds up to turbo abuse, but it is $3k.  There’s not too much that can be done in the tranny besides getting all the gears shot peened, etc.  But any time you put in twice the load that something was designed for, it’s going to fail much sooner.  Double the power also means double the heat, so tranny and diff coolers recommended. 

The only Mustang that seems to be track worthy is the Boss 302 Laguna Seca edition.  It comes with an oil cooler, baffled oil pan, an air scoop for the transmission, and a beefy Torsen rear diff.  It comes with the upgraded Brembo brakes, vented brake shields, brake ducts, and reinforced brake lines.  So Ford did basically everything I did to make a reliable track car that only has 7% more power (less peak torque though) than the regular GT.  Imagine what they’d have to do it make it reliable at double the power!

And at this winter track day, I was quite a bit faster than a brand new Mustang GT, though that may be due to driver ability.  I was also significantly quicker than a new, stock, Evo X on fresh tires though unknown on driver ability.  They’d both pull me on the straight pretty easily, but I’d eat them up in the corners.

There is one very very serious time attack S2000 build that is being shown in Modified.  He went with the Puddymod rear diff and made his own rear diff fluid cooler system.  He ditched the stock S2k tranny completely and went with a stronger, race purpose tranny.  He’s running an Accusump to prevent oil starvation and I think he’s going to be using an EFR8374.  So that’s a 700whp turbo (750whp pushed hard).  Lots of crazy body work and venting for heat management.  Of course, he has the benefit of being a purpose built race car so he can ditch things like the A/C condenser to improve cooling.

Well, point is, power = a lot more stress.  Also, it’s easy to make something last for 15-30 minute sprints.  Quite another to make it built proof over a 24 hours endurance event.  Fatigue life follows a logarithmic scale, so doubling stress reduces fatigue life by 1000x.  Which is why it is difficult to make a bulletproof track car.  A few years back in time attack, there was the Design Craft turbo S2000.  I think it spent roughly 10 hours getting fixed/wrenched on for every hour it was on track.  I felt bad for the mechanics as they always seemed to be working on the car at every event.

Posted By jere on 01-30-2012 10:15 PM
Wow 9K for a turbo kit?! I would be looking toward DIY for that money, and then maybe pick up a back up car with some money left over. Seriously 20k for upgrades, is a little high don't you think? Or are you paying someone else to install all the parts or something?

That's doing all the work yourself.  Going fast AND not breaking ain't cheap!  There's a reason why the new turn-key racecar Ford Focus ST cost $100k.  Personally, I don't think the PTuning manifold will hold up to extreme use, i,e real racing and not just a track day. Though I suppose, it could just be considered a wear item and just get it rewelded or have a spare laying around.

Back to the S2k.  PTuning kit is roughly $9k in cost alone, not installed.  Add in an exhaust, $1k.  I personally think it needs a bigger oil cooler.  Add in tranny and rear diff oil coolers.  Roughly $1500 for the heat exchangers, lines, pumps, fittings, brackets, etc.  Puddymod rear diff, $3k.  Vented hood.... there are a few different ways to go about it.  Let's say DIY so it's free except for your own time.  Or a cheap one for $700 if you don't care about the quality of it.  The front openings really need to be opened up, but some custom work with a sawzall can take care of that, freebie.  A set of stiffer motor mounts to handle the greater torque, $350.  Ideally, get the gears in the transmission micropolished and shotpeened, but we'll skip that.  Oh yeah, radiator, $350 for a Koyo.

Not including labor, we're past $15k already.  Oh yeah, forgot about the clutch, $550.  HASPORT rear diff mounts, $300.  I think you can put in the OS Giken diff with the Puddymod beefed up rear diff, so you can tack on another $1600 if you want, though I think the money would be better spent taking the tranny apart and strengthening the gears.

Building a mixed street/track car for a 25hr race is a bit overkill, but since the idea is a pain-free fun track day car, I suppose it makes sense. At the same time, it is understandable that since you have already improved the car's strengths that you wouldn't want to mess too much with a well balanced package.  Plus, keeping it NA seems closer to the original S2K concept.

Thinking out loud...has the rotrex supercharger idea been thrown around before?  That might let you bypass the cracking turbo manifold issue, though the extra stress on transmission/rear diff doesn't go away.

Off topic, but I remember an article where Mike said the Cooper S is a great track-ready car out of the box. It'd be interesting to see a MotoIQ Project Cooper S for the purpose of taking a detailed look at just how well equipped a stock or near stock Cooper S is at surviving a 25hr race (or at least meeting that goal based on track test results, like the Project S2k has been subjected to).

 Ironically, someone started a thread on s2ki.com about how much money they've spent:

http://www.s2ki.com/s2000/topic/926...you-spent/

I'll quote a few:

"Other then coilovers, wheels/tires, I have always looked for deals on used stuff to help save money, but after owning the car for 7 years and putting about 200k on it during that time. I have spent an easy $25k in upgraded performance parts, two replacement motors, two trans and three rear ends."

"I'm right at $15k for my turbo kit setup with fuel system. This includes tunes, clutch, labor, AEM EMS with gauges, powdercoating, exhaust fab., etc  Boost is expensive! "

"Well I actually log every purchase and every hour spent so that I can accurately show people how long and expensive it really is. Not including the car the Greddy build was right at $12K including clutch wheels, tires..... at the end of the IP build I was sitting at $25.5K and by the time I sold the car with the Mase Kit I was up to $36K. Total was about 107 line items ranging from oil to complete turbo kit. Take out the sale of the all the parts and the net loss was around $10-12K. Then you figure in the time and at my billable rate of $60/hour well, let’s just say it was a BIG NUMBER. 

Flash forward to my current build, I have learned a lot of lessons and now know the trusted vendors, what I like and want and what works. I figure I can build a reliable turbo setup able to take to HPDE days, shows and drive around town laying down 550ish WHP on a budget of $23K not including the car with about 150 hours invested. As it stands I have spent $13K and 3 hours but the car is stock with exception to SOS hood struts and being pretty clean. The final trick is the sale of the parts and I am shooting for a net loss of only $5K if I sell within 1-2 years.

To be honest I don't think I will hit my budget but I am looking for deals and taking my time. I have 10K for the turbo kit but that includes dual 340lph pumps, ID1000's, Fuel rail, Haltech, Flexfuel sensor, radiator, boost modulated cutout, powder coating, ATP heat shielding, oil cooler, cams, valve springs, MAP, boost solenoid, pulgs, hoses........Add it all up and the number is a bit light. 

Complete Turbo Kit w/ Fuel Management...........$10,000
Clutch..........................................$700
Wheels and Tires................................$2,700
Hardtop.........................................$2,500
Brakes..........................................$2,700
Suspension......................................$2,000
Paint & Body Work...............................$1,000
Misc Interior and Accessories...................$1,000
Differential w/ LSD.............................$3,000
=======================================================
Total...........................................$23,600 "

Posted By M-P on 02-01-2012 09:38 PM
Boost is quite expensive, but what "Differential w/ LSD" is $3000? Seems like that guy paid someone WAY too much.

The Puddymod rear diff is $3k.  It's a super fortified S2k diff that's much much stronger than the stock unit.  It's the only one to get if you have a boosted S2k as everything else will break.

There's a big difference between boosting a car that's a DD and gets beat on once in a while for HPDE (been there, done that) as compared to a car that's meant to be beat on mercilessly.  My old Nissan SE-R, I boosted that and made more than double the stock HP for 80k miles.  I tracked it once in a while and auto-x'd it quite a bit.  However, I always had a keen eye on the water temp gauge, I faded the brakes a few times on a road course, and I never used 3rd gear on the street for fear of grenading it (see Project G20 racecar at Las Vegas MPTCC).  I picked up a G35 sedan for a DD and I would have no issues at all boosting that as it's just a DD; it won't see much stress at all.  Like I said, someone give me $20k and I'll make a reliable boosted S2k that can be beat on mercilessly 

Posted By spdracerut on 02-02-2012 12:10 AM

Posted By M-P on 02-01-2012 09:38 PM
Boost is quite expensive, but what "Differential w/ LSD" is $3000? Seems like that guy paid someone WAY too much.

The Puddymod rear diff is $3k.  It's a super fortified S2k diff that's much much stronger than the stock unit.  It's the only one to get if you have a boosted S2k as everything else will break.

Crazy...was not aware of that.

Posted By Mike Kojima on 02-02-2012 10:16 AM
I know Steff Papadakis converted his drift S2K to a Nissan R200 diff to solve the weak diff issues.

InlinePro makes a R200 diff install kit for $3600.  Does NOT include diff.

http://www.inlinepro.com/s1/p-31-s2000-diff-kit.aspx

I'm weary of it though..... I figure the less I mess with the OEM setup, the better as I don't know the level of engineering that went into the kit.

I know there is at least one British tuner that has been using the (r200) 300zx diff on their supercharged s2000 running 600ish whp. Though I don't think the kits where very cheap. I will and try and find the article about it if I can as I think they were one of the first to do it.

In terms of DD vs boosted track machine I think it is hard for us without the experience to imagine the stress and issues involved in running a competitive boosted racecar and think "well it can';t be that much more difficult". Though it is my understanding that many of the big NA machines (ie. LS series ) have heating issues as well.

I suspect the s2000 has handling that can make it a great hpde car without the risks involved in turocharging.