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Old 07-08-2013, 10:27 AM   #4
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Join Date: Oct 2005
Location: GA, USA
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...continued from above...
  • Single Turbo (Large), Aftermarket Fuel, Aftermarket ECU, Stock engine internals (800rwhp-1050rwhp): Still want more? Time for an even bigger turbo, a full fuel system upgrade, aftermarket cams w/double valve springs, an aftermarket ecu, a bigger intercooler, an aftermarket intake plenum & throttle body, a triple plate clutch, and a shot of nitrous to quickly spool up that big turbo. I hope you've been saving some $$$ - each step of this journey gets significantly more pricey than the previous one. However, these parts are all 'off the shelf' - little to no customization is necessary at this level. It's the customizations that cost the really, really big $$$ amounts. By restricting your mods to stock internals, off-the-shelf parts, and a large but not huge turbo (eg. 72mm or 76mm), you can still contain the costs to a semi-sane degree.
    • It's probably time for pure race-compound (R-rated) tires, and a widebody kit or fender flares to handle 13" wide rims and 335+mm rubber.
    • Use pure high octane race fuel (eg. at least 110 MON) in your gas tank to avoid detonation at this 30+psi boost level. About 850rwhp (1000hp) is achievable at this level. Above 850rwhp you'll need to use a more exotic fuel, like c16 or vp120 import.
    • Instead of alcohol injection and race fuel, you can consider E85 if it is readily available in your area. This is still an off-the-shelf fuel system, but the injectors are much larger. Get an aftermarket ecu that can dynamically adjust your fuel curve and your max boost level based on the (often-inconsistent) alcohol:fuel ratio in E85.
    • You'll benefit from a mild port & polish on the head at this stage. Might as well get the valve seats re-cut too - don't skimp: make sure you take it to a head shop with a Serdi machine, 7-angle on intake and full radius on exhaust.
    • A standalone ecu takes a significant amount of time for an expert to get right for your exact setup, in all driving conditions. As with the previous step, don't skimp on tuning.
    • If you didn't upgrade your suspension before now, it's time for (at least) some Tein or HKS coilovers, adjustable swaybars...unless you're drag racing. For drag racing, you'll want to disconnect the front sway bar, and run slicks + skinnies.
    • Get ready for the real fun. At this level, you'll be able to embarrass most motorcycles and high-end exotics.

      You can now literally ignore most performance street cars (unmodified or mildly modified, foreign/domestic it makes no matter), because they're not even remotely any challenge - it really seems like they've stepped on their brakes when your boost hits.
  • Hog Wild - 1200rwhp-1500hp+, but still amateur: Above about 1100rwhp (6spd), you'll need to "build" your 2jz-gte's internals. It's only the connecting rods that can fail at the 1100rwhp level, and then only with nitrous usage. I have reliable reports of the oem pistons being good to at least 1300rwhp (6spd). The $$$s are 'hog wild' too at this level, so if your budget is restricted in any way shape or form, I'd suggest you stay in the previous category.
    • Go for the best connecting rods (Carillo), pistons (JUN), bearings (Clevite), head studs (ARP L19, or oversize), etc. You'll need to find a machine shop *experienced race-building the 2jz-gte* in order to not have things fail. If you experiment with inexperienced builders, you're essentially overpaying to educate them.
    • For 1500rwhp+, you'll need to think 3.4L stroker, and aftermarket main caps.
    • You'll need full head porting and oversize valves (Ferrea). 1mm oversize can be done with the oem valve seats (272 cams, 1300rwhp-ish), but 2mm oversize requires aftermarket valve seats (280 cams, 1500rwhp+).
    • Massive turbo (88mm+) - depending on application. For extreme high-end roadracing, a current-technology ~72mm turbo will be fine, but you'll need much more suspension work (Penske/Moton/Ohlin/etc.) and cooling mods.
    • This fuel system is custom (i.e. not 'off the shelf'):
      • Triple fuel pumps in-tank, or large-flow external (race) fuel pump.
      • Huge fuel lines and fuel injectors. Direct port nitrous.
      • Ultra-high flow fuel pressure regulator
    • Race fuel, race fuel, race fuel. Think VP Import or C16 - either of which is probably about $25+/gallon. Also think 35 to 40psi of boost, and beyond. The only way to run those boost levels without blasting your pistons...any brand of smithereens is by using the very highest octane race fuel.
    • Triple or quad plate, triple-carbon clutch...or fully built race transmission (non-Toyota)
    • 4"+ exhaust (preferably titanium - ultra light)
    • Fully tunable suspension (Penske, Moton, Ohlin).
    • etc., etc. (lighten the chassis, install a roll cage, aftermarket LSD, etc.).
    • Tuning, tuning, tuning. With the right race fuel and 40psi+ of boost, timing and your air/fuel curves have to be as close to perfect as humanly possible in order to get the 1300rwhp+ results you're looking for. You may need to fly in an expert tuner from out of town, and be prepared to shell out the cash needed to put your car on the dyno for at least one more full days.
    • If you have any specific questions about specific configurations at this level, please ask.
    • Unquestionably, assuming your driving skills are well-honed, you'll rule the streets and many (amateur) race tracks (in the same class of car as the Mkiv Supra Turbo - 'GT Sportscar'/hatchback). No bone stock car except $500K+ ultra-exotic 'supercars' or pseudo-street cars (eg. Porsche GT3) will even come close. You'll also have fun with other highly modded Supras, highly modded Vipers, highly modded Vettes, highly modded Skylines, and modded Lambos. I can't guarantee you'll win every race, but I can guarantee you'll be competitive - most likely it'll be the driver and not the car that holds you back.

  • Pro race series: Almost everything at this level is proprietary, if the race team is currently competing. Why would they share anything with their competitors?
    • Most (but not all) of the mods at this level are only a few percentage points better than the top amateur mods in the category above. However, those few percentage points often mean the difference between winning and 2nd place.
    • Many of the mods at this level are practically useless for a daily-driven street car. For example, you'll never get 300,000 miles out of a set of titanium connecting rods.
    • All that said, I'm sure we're all interested in anything any pro race team member that previously or currently raced/races anything equipped with a 2jz-gte is willing to share with us!!!!

If you've carefully studied the categories above, you'll see a bit of a gap between small-to-mid turbo (650rwhp) and big single (800rwhp). If for some reason you want 725rwhp (specifically), of course an Mkiv Supra Turbo can be built to that level, basically using a mix-and match process from those two categories of mods. However, you'll likely find that you may not end up spending very much less at 725rwhp than you would have for 800rwhp...which is why I essentially skipped over it in the modification categories..

Auto transmission: Subtract about 10% more rwhp (for the same crank hp vs manual trans.)...depending on whether it's a built or oem transmission, and whether or not it's a high stall torque converter (TC, with or without lock-up). The oem auto TT tranny can hold about 500rwhp to 575rwhp...depending on how hard it's driven and how wide & soft the tires are. Drifting with (for example) 13" wide R-compound rear tires will limit the auto tranny's holding power to ~500rwhp, reliably. Oem-spec rubber and no 'hardcore' racing it'll hold 575rwhp reliably. A 'fully built' mkiv oem tt tranny (eg. by Sound Performance or Boost Logic) with aftermarket high-stall TC will hold up to 700rwhp reliably. Past that point, you'll need a purpose-built TH400 or 4L80E customized specifically for the Mkiv Supra Turbo; a TH400 built for a large-displacement V8 (same rwhp) will fail 100% for sure.

Hopefully you found all of that interesting. In short, the Mkiv Supra Turbo really is an incredible vehicle that will allow you to compete at almost any level of performance. As it is with any other motor sport (bikes, cars, boats, planes, etc.)'s mostly a matter of how much $$$ you throw into it (especially at the highest levels) well as how much time the driver has invested in increasing his/her skill level. If you start with an Mkiv Supra Turbo, I sincerely believe you will not be disappointed in the outcome, regardless of your ultimate goals.
Phil '94 Supra Turbo, 6spd, 'APU'+
Displacement is no replacement for boost.
Life begins at 30psi.

NB: Please consider posting any help requests in a new thread instead of asking me for help privately. About 99.9+% of the time, private help requests end up covering great information that could be very valuable to other forum members. If you have a good reason for needing the help request to be private, I'll consider it. If not, then why not give everyone else the opportunity to pitch in too, and/or learn from the information? Remember, there's no such thing as a dumb question. We're all here to help within this family of Supra owners.

Last edited by pwpanas; 10-12-2014 at 01:40 PM.
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