[@Green]

SP ENGINEERING TESTS HKS 264/264, 272/264 AND 272/272
CAMSHAFTS
http://WWW.SP-POWER.COM

Text By: Ken Henderson and Ju-Hon Chan

THE ISSUES:
Whether or not a reverse stagger cam set-up enhances turbo spool-up, mid-range power and the ultimate power potential of the head from the Toyota 2JZ-GTE engine;

Whether or not a parallel cam set-up is inferior, or superior, to a reverse stagger cam set-up in terms of turbo spool-up, mid-range power and ultimate power production of a given engine/turbo/drive train set-up;

What are the differences, if any, in spool-up and power production when the parallel HKS 264/264 and 272/272 cam combinations are compared?


THE CAR:
Those of you familiar with our testing of 4-inch big bore exhausts for the MKIV Supra Turbo will recognize this car. Sleek, black and stock-bodied except for the carbon fiber TRD hood, it represents all that we know and love about the JZA80. Owned by Ju-Hon Chan and built by SP Engineering of the City of Industry, California, the vehicle had already under gone significant upgrades to the engine, turbos, suspension, wheels and tires and engine management prior to its latest round of improvements.

Chan decided to swap in twin Garrett DBB 3071 turbochargers in place of the previous HKS DBB GT2835Rs and install bigger cams. Since re-tuning the engine management system (EMS) would be required as a result of these changes, it was decided to conduct testing of various combinations of cams so as to provide some clarity to the ongoing discussions on SupraForums as to whether parallel or reverse stagger cam combinations work best for a given engine set-up.

Going into the testing, the critical elements of the engine’s set-up were as follows:

--A built shortblock with Crower billet steel connecting rods, forged, .040 overbore, JE pistons (with Total Seal rings) and a lightened, balanced and micro-polished OEM crankshaft;

--A ported and polished cylinder head, complete with a Ferrea valve train (stock size valves), including locks, locaters, keepers and titanium retainers and HKS 264-degree camshafts, both intake and exhaust;

--A VeilSide intake manifold, including 100 mm throttle body, surgetank, billet fuel rail and lower intake manifold;

--An HKS twins set-up kit with dual manifolds, downpipes, racing wastegates, twin Garrett 3071 DBB turbochargers and custom 100 mm SP Engineering intakes;

--SP Engineering fuel system, including dual OEM/Denso and HKS/Denso fuel pumps, 1000 cc fuel injectors, a VeilSide billet high-flow fuel rail, TRD fuel pressure regulator and related high performance fuel system components;

--A GReddy 3-row, front-mount intercooler, GReddy Evo II 4-inch exhaust system and HKS F-CON V Pro EMS, along with the HKS Knock/Amp wide-band O2 sensor and air/fuel ratio meter.


THE FACILITY:
As with Clash of the Titans (http://www.to4r.com/special.php?id=1) and Clash of the Titans II (http://www.supraforums.com/forum/sho....php?t=280947), testing of the various cam combinations on Chan’s car occurred at SP Engineering, located in the City of Industry, California. The company’s Dynojet chassis dyno was used for determining the results of testing the various cam combinations and Jason Reinholdt, chief engine builder, once again provided the key technical assistance necessary to bring the results of this testing to fruition.


THE TESTING:
Because Chan was so excited about the prospect of testing, he forgot to empty his fuel tank (by driving) of the 100-octane unleaded fuel it contained. The day of the testing arrived with the tank being more than half-full so the testing was conducted with the 100-unleaded which has a MON of 96. Since the 264-degree cams were already installed, it was logical to begin the testing with these cams, followed by swapping a 272-degree intake cam along with the 264-degree exhaust cam and finishing up with the parallel 272-degree cams for both the intake and exhaust. During installation, the valves were shimmed, as required, and cam timing was established with a degree wheel and dial indicator. To eliminate as many variables as possible, no tuning of individual cam set-ups took place. The idea of maximizing each cam set-up through tuning was certainly tempting, but not tempting enough to, potentially, undermine the integrity of our testing protocol and introduce additional variables over which we had no control. We believe the results of the testing to be reliable and repeatable if the same installation/timing procedures are followed by other testers. On the day of the testing, boost was limited to 1.5kg/cm^2, or 21.3psi.

Добавлено спустя 5 минут 57 секунд:
Dyno #039 is the baseline run with the 264/264 cam set-up right after the installation of the Garrett DBB 3071s and clutch rebuild. A safe tune with 100-octane unleaded and a boost setting of 21.3 psi was decided upon by SP Engineering for comparison and used for each cam combination tested.

Dyno #057 is the dyno graph that shows the results when the 264-degree intake cam was removed and a 272-degree intake came installed in its place.

Dyno #060 is the dyno graph that shows the results when the 264-degree exhaust cam was removed and a 272-degree exhaust cam installed in its place.

In conclusion, the dyno graphs above, essentially, mirror HKS’ own testing results as shown in the dyno graphs below taken from its website. Moreover, and the primary reason why this testing was undertaken in the first place, our results showed that reverse staggered cams, in combination with the poor flowing (relatively) exhaust ports of the 2JZ-GTE cylinder head did not show improvement to the motor’s power band. In fact, the reverse staggered cam set-up increased spool and took away from the motor’s power band at all levels, low-range, mid-range and the top end as well. Additional information on the 2JZ-GTE cylinder head can be found (http://www.to4r.com/techarticle.php?id=5) in an excellent article written by JZA80 guru Lance M. Wolrab.

Добавлено спустя 1 минуту 4 секунды:
For those interested, the final dyno results at 2.2kg/cm^2, or 31.2 psi, with 100-octane unleaded, yielded this (This dyno involved tuning to optimize the car’s 100-octane map and a lot more boost than was employed during the testing!):

Since, we were stuck using 100-octane unleaded, not much could be done with timing and the results reflect this. With a tank of VP 109 Motorsport Unleaded (MON of 101) or, better yet, C16 (MON of 117), and tuning to take advantage of the higher octane fuel, we feel confident, this is a 900+ whp car, but that’s a story for another time. Thanks to all who have read this far and find the results useful.


Ken Henderson
Ju-Hon Chan

[@koskos]

зачетная тема!!!

[@Green]

Всегда пожалуйста!

[@koskos]

найти бы тесты Титановских 264ых и 272ых валов,
это график с 280ыми HKS впечатляет, и цена адекватная:
http://www.titanmotorsports.com/titan-m ... jz-2s.html

[@Матрос Железняк]

Green, там поройся на форуме, было тестирование сток-валов vs 256 и 264

[@bocha-x90]

Green Можешь перевести на русский а то по англиски не шпрехаю

[@koskos]

google рулез

[@bocha-x90]

нет у меня гугле и не рулю я там ну не как не получается