yes, due to the lag.

 

I am just telling you my experience. Dutchboy has the aps extreme kit on his car, and his car is very smooth and keeps pulling. The power dilivery is awsome and very linear. While I have noticed that in my friends greddy kit, the power comes on very quickly and seems to drop off around 6k. Both of these car have been tuned by by Forged Performance. I am not saying one is better than the other, I was just telling you my experience and I am sure pretty sure dutchboy will back me up. Both kits are very nice IMO, but I would choose the larger tubo's over the standard ones anyday.

 

While the car is driving in what you call lag, the car seems to drive like a non-boosted 350z. Once again this has been my experience.

 

no worries. I have felt differently that's all. I've had both, and currently running the extreme.

 

First of all lets see what do we mean by larger turbos. There are many setups. By using let's say the same turbine wheel and changing the compressor, the amount of gas flow required to spool the turbos are practically the same. The volume of delivered boosted area is higher a the same Turbo RPM. Ofcourse the turbos will delay more than with the smaller comrpressor, but the affect will be unoticeable. The boost peak will be transfered towards right side of the RPM range.

This is the issue actually with the APS setup. After my research with Garrett, my mechanic and APS, I came up with following. The Standard APS TT is using the GT2871R turbine. The extreme is using the GT2876R. Theese turbos are using the same turbine with different compressor wheel. Bellow are the values obtained by garrett.

GT2871R 743347-1 compressor 49.2mm 71.0mm A/R 0.60 turbine 53.8mm A/R 0.86

GT2876R 705330-2 compressor 52.7mm 76.0mm A/R 0.70 turbine 53.8mm A/R 0.86

Thus easily you can install larger turbines for our setup by using exactly the same flange dimensions / manifolds, of basic APS TT setup. The air side will be different but there is not any problem that Silicone ducting can not solve.

 

I highly doubt the normal APS TT kit uses GT2871R's. The Turbos look too small to be a GT2871R. I remember MRC sending on to Garrett to have it diagnosed and they said it was a GT2560R.

I've looked at my Turbos and have looked at a GT2871R, the APS turbos seem smaller. If a sponsor would like to chime in . . .

 

https://my350z.com/forum/showpost.ph...9&postcount=24

So it is a GT2560R.

 

+1 !!! My friend with his JWT 850-very similar to APS TT, full boost around 5000rpm's hooks up with 700whp, I can spin at 60mph in 3rd with 525whp if I dont peddle it...my car is much more violent in its power delivery.

 

so do big turbos even have enough time to reach their peak boost when in 2nd gear?

 

They surely do not look like the 2560s. In any case I am dismantling them today to take it to Garrett. The compressor casing is APS custom made. The Inlet is from the 28s while the outlet from the 25s. Air ratio of 0.8 does not exist on either 25s or 28s. I am going to measure and see what is going to be the perfect match if any. Anyway thanks for the tip man.

 

I will look and see if I have the specs at the shop from Garrett. WE sent them out for inspection to se, and they were a GT25 with upgrades to make them equivilent of a GT28.I cant recall all the specifics,but were supposed to be good for 350hp worth of airflow each. The extreme kit is basically a GT28-upgraded to a GT30r I believe...good for about 400-450 each. The standard kit reached full spool up by 3600 whereas the extreme hits full spool by 4300 ish..

 

Yeap I fully agree with U. I suspect that the cartridge are coming from the 2871R, with the custom made compressor housing and standard turbine housing. Direct replacement is the GT3071R. Even the turbo dimensions are the same. First turbine trim is 76 and the large is 90. They are using exactly the same turbine and compressor housings. I will have the details tommorow. I am planning to take the cartridge out of my turbine and replace it with the GT30's, using same compressor and turbine house.

 

Violent power delivery FTW

 

Thats my preference, I can modulate the throttle and control the power to put it down, Id rather have extra power-more usable powerband and control it down low than not have good power down low and wait till later...

 

I have dismantled the turbos, took them over to GARRETT. They agreed that this is a custom made Turbo built for APS. The range stands between the 25ths and 28ths. Turbine is coming from GT25 with 0.64A/R. The compressor housing is coming from a GT2554, machined to accommodate the compressor wheel of the, 2871R.

I have purchased the 3071R with 0.64A/R. The manifolds can accommodate them. The only drawback is the vehicle structure. This weekend I will try to fit it and see how I can get this right. I will revert with photos.

 

Where can we get these turbos from if they ever fail us? Directly from APS?

 

Yeap In APS, and only APS. Theese are custom made

 

The assembly might be custom to APS but the individual components are not, so anyone that is a Garrett dealer/shop can fix them.

 

Correct. Garrett can fix the turbos, but to buy a complete set, you need to go to APS directly.

 

i believe the standard aps turbos are ideal for what your looking for unless your going for huge top end and 600rwhp+

if starting from the begining then i would get the extreme but the standard is more then enough


i may upgrade to external wastegates later but for now im happy

this is z06 with stroker and all the goodies against my aps tt