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Some updates. This is a result sent in from Toshi, based on a Manual Skyline with our high flowed OP6 turbocharger. Made 277rwkws on 17psi, P 98 fuel.

op6hiflow377rwkw.jpg

Little update on the ATR28SS series on sr20det engine.

This particular prototype is a modified SS15 in a .64 rear, how ever the modification did not take effect. How ever still made a reasonably responsive 255rwkws @ 18psi on pump 98 fuel.

power.jpg

boost.JPG

This turbocharger against the most responsive GT2871R in .64 turbine housing run, and beats it in both power and response:
vsgt2871power.JPG

vsgt2871boost.JPG




I also conducted a test evaluating factory 2.5 inches induction pipe Vs a 3 inches induction pipe. Results as shown:
25inchpipeincar.jpg

Differences is 13kws at 255rwkws application: Red is with 2.5 inches induction pipe, while Green is the normal 3 inches induction pipe.
inductionpower.JPG




inductionboost.JPG

  • Like 1

Your still getting a fair bit of boost drop cause you using the 1bar actuator

Your boost is going from 20psi to 17 psi by redline

Mine held 20psi pretty solid with your 20psi actuator you supplied with the normal 1/2 a hole preload as seen in my dyno

I know most people leave the standard twin turbo intake piping on GTR's but has anyone actually done some back to back runs like above to see if there is an increase in power moving to bigger piping or are the turbo's too small to bother?

I was modifying 300zxs for a couple of years and induction pipes on them do make a very noticeable difference. So I believe proper induction pipes can also affect GTR's performance in a positive way.

  • Like 1

I was modifying 300zxs for a couple of years and induction pipes on them do make a very noticeable difference. So I believe proper induction pipes can also affect GTR's performance in a positive way.

When I get home I will post up dyno sheets of z32s 2" vs 2.5" piping...the difference is around the 40rwhp mark. A gtr may not gain that much however, a z32 has around 2.5m of chqrge piping on each bank.

Edited by Super Drager
  • Like 2

Ok as promised:

Piping comparison:

EX000002.jpg

P0003549.jpg

The car was tuned with the ZEM in its original setup with the 2" OEM piping and Stillen SMICs. Once the tune was perfected with this setup and all of the runs were made, the only thing that was changed was the intercoolers and piping. The exact same programs were used in the second test as was used in the first (there were three different programs created along the way to handle pumpfuel, racefuel, and maximum boost).

1.2BAR:
DynoCompare1.2bar.jpg

1.3BAR
DynoCompare1.3bar.jpg

1.4BAR:
DynoCompare1.4bar.jpg

1.5BAR:

DynoCompare1.5bar.jpg

1.6BAR:

DynoCompare1.6bar.jpg

1.7BAR:

DynoCompare1.7bar.jpg

1.8BAR:

DynoCompare1.8bar.jpg

After looking through the data to see where the differences were in the other datalogged pieces of information, it is obvious to see that the engine is simply breathing more air, especially down low with the larger piping/intercoolers. The A/F is a bit different between the runs on the bottom end simply because it is using a different part of the fuel table as a result of the additional airflow. More air = more fuel delivered = richer mixture. On the top-end of things, the A/F is slightly different as well and it will account for some of the improved power. I did not want to change the programming that was used as I felt that this would lead to possible suspicion by some folks. If I had adjusted the program to make the A/F the same, the difference in numbers would have been even more dramatic through the bottom end up to midrange, showing greater improvement in bottom end, and with a slight detriment to top end power as it seems to want to run a tad bit leaner with the new setup, albeit a rather marginal difference though. It would be even nicer to see the difference if Dee's car had 60mm throttlebodies, which are essentially the same size as the 2.5" piping we installed. Even despite this limitation, it was apparent that the piping and intercoolers contributed quite a bit on their own. I believe we were really tapping out though on the benefit of the piping/intercoolers as the power was increased on the top end because of the limitation of the throttlebody. At this peak power level (650RWHP), there is a tremendous amount of air flowing through each throttlebody and I believe the 2.0" OEM throttlebodies started to become our bottleneck.

So, this is the preliminary dynochart data and qualitative review of what I see so far and as soon as I get everything together in the quantitative analysis department, I will be more than happy to share it all.

Just food for though :)


Turbos are GT28RS (2860-5). Pump Fuel until 1.6BAR, C16 from 1.7BAR onwards.

Edited by Super Drager

Thanks for posting it.

The more air= more fuel = richer mixtures comment is a bit odd though.

Possibility he is running AFM(s), so more air "sensored" by the AFM, more fuel is injected - accordingly to the map.. where as a MAP based car will inject as much fuel as required as per the RPM vs. Boost/Vacuum cell.

Possibility he is running AFM(s), so more air "sensored" by the AFM, more fuel is injected - accordingly to the map.. where as a MAP based car will inject as much fuel as required as per the RPM vs. Boost/Vacuum cell.

If anything it would be because the higher load cells are probably richer (assuming a stockish fuel map).

Actually after I replaced the stock R33 rubber induction pipe with a proper 3 inch metal item. My fuel actually went lean in upper revs. It has to be touched up.

When I get home I will post up dyno sheets of z32s 2" vs 2.5" piping...the difference is around the 40rwhp mark. A gtr may not gain that much however, a z32 has around 2.5m of chqrge piping on each bank.

not sure why we're comparing intake piping to cooler piping but its nice to know the difference it makes

was the turbo slightly more laggy with the bigger piping as a trade off from response to more top end power?

Upload a video. Which we machined a bunch of comp housings today using CNC:

The comp housing profile was done by CNC too, except the lathe tip is sprayed with oil that can't be seen. Takes about 10 mints to complete a comp cover from Castings. Which working by hand would roughly be 70 mints.

  • Like 1

Add in another update. This is our latest TD06SL2 based turbocharger, the SLSS-2 in 10cm turbine.

This particular one has the latest low friction trust setup, with slightly larger compressor inducer and slightly more aggressive compressor blade profile. It should be maxing out around 390rwkws mark working with a RB25det engine on E85.

It is made to produce more power, with better response and much better reliability to some of the T67 copies

Will update results shortly.

front.JPG

rear.JPG

.

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