| After i finally got my car running right and all the maintenance issues (i.e. cooling issues) have been worked out, last friday I took a trip down to Woodland Hills and Southern CA to see the Z whiz Greg Dupree and Seb from SpecialtyZ. The distance from Northern Cali to Southern Cali isnt like taking a trip to the local 7-11, but I can say in the end it was all worth it. This is the second time SpecialtyZ has tuned my motor. In its previous incarnation, old mods include: HKS 2530 Turbos
SpecialtyZ inconel tubular manifolds (discontinued)
2.5 inch SZ original split downpipes
2.5 inch mid pipes
2.25 inch HKS turbo exhaust
555 cc injectors
JWT dual pops
fisher crank pulley
Apexi SAFC
Greddy smic w/ stock size IC piping
stock bottom end
stock heads, stock cams at 1.85 bar of boost, it made 583 rwhp and 544 lb ft / tq and at 2.01 bar it made 610 rwhp and 572 lb ft / tq. 
That is my old Z - my current Z has the same engine, tranny, suspension, same wheels, and most of the mods off this superwhite Z were pulled and transported to the plat. mist Z. I still miss her though to this day. :(
Here is the new mod list (new mods are highlighted in bold )
HKS 2530 Turbos
SpecialtyZ inconel tubular manifolds (discontinued)
3 inch SZ expansion downpipes
3 inch mid pipes
3 inch custom HKS carbon-ti exhaust
740 cc injectors
JWT dual pops
Tom Green 4.5 inch thick smic w/ 2.5 inch IC piping
fisher crank pulley
stock bottom end
stock heads, stock cams My plan for the car has always been as long as i've owned it to be a reliable street car with a healthy powerband that, full AC and interior, and if i ever wanted to take it to the strip and /or track and have fun, I could do that without making major changes to the setup. I've never wanted (at least for this z) to have a car that makes most of its power over 6000 rpm or to win some internet battle over rwhp numbers. If I wanted to make just a lot of peak power on paper, i might have gone with a custom setup or a 2871R (725) when my engine was pulled. Greg's take on turbo choice is that i am fortunate that I didnt choose the 2871R being that the turbine and compressor wheels are mismatched - the 28RS compressor housing is machined to fit a big 71 mm wheel, while the 28RS 54mm turbine wheel and its housing is untouched. = lots of lag, high egts and lots of backpressure. I decided to get 3 programs, for 91, 100, and 116 octane maps. The ECU setp is pretty trick; it can hold up to 16 different programs and a toggle switch flips back and forth between programs at your convenience. Alcohol injection was pretty much turned off during tuning, as I use it more as a safety against detonation on pump 91 rather than depending on the alky for increased boost and timing. The increase in power at all boost levels was attributed by Greg to the 2.5 inch Toms Turbo IC piping and the SpecialtyZ 3" expansion downpipes. allowing the exhaust coming off the turbine wheel to exit in a gradual transition and proper separation between the exhaust out of the turbine and the air coming out of the wastegate when it opens = less turbulence and more of a pressure and heat differential before and after the turbine which makes the turbo more efficient. Allowing the engine to breathe in and out better increases power in all respects. Greg and Seb were great and answered all my tech questions honestly and with no Bs. I appreciate the advice freely given and that they are willing to share what they have tested and learned. Excellent job of tuning! good luck with your projects. That drag z is / was / will be a beast!! LA is a great place to visit but.....you know the old saying. Nearly 5 minutes after the dyno closed shop and we all were set to head out, I nearly got clipped by a mustang that pretty flagrantly ran a red light! I mean it must have been at least a few seconds after the light turned green for me. Thank God i saw him out of the corner of my eye and for my Wilwood Big Brake kit, or this post would be very bittersweet indeed! He missed me literally by 2 feet or so. The moron kept barreling down the street. I also got lost several times. The funny thing is, during the time i was in LA, i saw a road rage incident that resembled a car chase scene from a movie, i saw numerous instances of tailgating and swerving throught traffic, i myself was tailgated by several cars on city streets and I was already going over the posted speed limit, generally alot of anti-social behavior. Pictures of the car: 
Rear strapped down 
Working their magic until past 9 pm on a Friday Night! 
ECU tuning via laptop and software > adjustments via SAFC by a landslide 
GDupree at the helm
 Draining the 100 for the 116 tune There issues with the dyno's wideband. Greg and Seb used their own innovate wideband and bosch sensor for these runs - target a/f ratio was 11.5 to 1.
 1.00 BAR
1.23 BAR
1.40 BAR
1.52 BAR 
1.76 BAR - FINAL NUMBERS -649 RWHP 569 LB FT TQ
Here is the STD corrected figures
Here is a comparison between the old setup and the new - the 3 inch exhaust and 2.5 inch piping gave me a lot more top end power, at a lower psi! The 609 rwhp was at 29 psi, which Greg has stated shouldnt be run on the street if you want your t urbo to live a long time, and a more reasonable (for a 2530) 26 psi. Id rather have more power at less psi any day.
Here is a more apples to apples comparison, 1.76 bar on the new setup and 1.85 bar on the old. I gained ~ 70 rwhp of peak power at the same boost level. I guess making that air pump we call an engine breathe in and exhale out more efficiently pays dividends, even with no internal work! The Z with the stock bottom end has kept chugging along for the past 3 years at boost levels over 500 rwhp very well. Solid as a rock. I havent had any major problems at all concerning how the motor has held up - I think thats a testament to how well Nissan designed the VG and how much we underestimated the strength of the bottom end just a few years ago when people were being told that at just 500 rwhp we needed a built bottom end. The SPAL 2470 e-fan has held up very well since i replaced the defective ash fan with it. On the trip to LA from the Bay Area, i only stopped once, after about 220 miles at Pismo Beach. Temps ranged from 195 to 172. But on the way back, there were several accidents on highway 1 where i was stuck in bumper to bumper traffic for close to 20 minutes at a time. Again, temps ranged from 196 to 177. I'd say its doing its job; i'm not saying that anyone should replace their clutch fan with an efan, as the clutch fan has shown that its durable and cools wee over th e years, but if you have to get rid of your fan due to space constraints the spal is not a bad way to go.
Very clean AMG in the dyno parking lot 
This little gizmo can switch between 16 different programs or tunes - to do so its as easy as flipping the + or - toggle switch and changing your boost controller to the desired boost 
50 hp right there?
2530'ed up!! xxx rwhp, yyy lb ft /tq tuned by GDupree and Seb from Specialty Z on 5/23/08
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SpecialtyZ tuned 2530 TT : 649 rwhp 569 tq, completely stock - 
01:19:24 05/28/08
