Powerfc or Nistune for r33 gtst and to E85 or not

[benl1981]

Hi there 

I’ve got an r33 with exhaust, intercooler etc. it has a small turbo upgrade. It’s a 2860 Garrett which I think people refer to as a disco potato with 0.64 rear. 

It’s super responsive. I know it’s not great for top end but thinking of keeping it as I should be happy with 220-240rwkw of responsive power. 

Currently it’s at around 200rwkw with 9-10pai of boost. It’s surprising as it seems to be the stock Ecu. 

Anyway, I can get e85 fairly easily around Sydney. 

If I install the 555cc injectors I have and z32 afm is there much benefit to e85 for this power range? Will you notice an increase in mid range. 

I feel like the turbo may be on the verge of surging as it boosts a lot down low, would e85 and turning up the boost potentially limit the benefit of the extra boost in the mid range you could run with e85 as it may be limited by surge?

I guess the decision of whether to go nistune or powerfc comes down the above. As if e85, then nistune would be better. Is anyone running flex fuel? 

I like the powerfc as I can install the new injectors and easily trim it all and drive to the tuner whereas nistune you need to buy the cable etc 

i have a z32 ecu but I see on the nistune website it’s not recommended, they recommend the r32 Ecu for the base of the nistune. Anyone had experience with the z32 or r32 computer in the R33gtst? 

Sorry, I know that’s long. 

In summary: 

1. Is e85 worth it for small turbos

2. What do you think of nistune for the r33gtst and does it work ok with the z32 computer?

Thanks

[GTSBoy]

1 hour ago, benl1981 said:

If I install the 555cc injectors I have and z32 afm is there much benefit to e85 for this power range? Will you notice an increase in mid range. 

Well, obviously you can't put the Z32 onto the stock ECU, so unless this was specifically for one of your ECU upgrade options, forget about it.

I would not install shitty old 555cc injectors into anything these days. Man up, buy 1000cc ish Bosch EV14 based injectors (or Siemens or Denso, or anything of the same vintage as EV14s) and win at life.  Better spray pattern, much much better spray at low pulse widths, even though they are double the size of the 555s. Also, much more headroom for E85,

1 hour ago, benl1981 said:

I feel like the turbo may be on the verge of surging as it boosts a lot down low, would e85 and turning up the boost potentially limit the benefit of the extra boost in the mid range you could run with e85 as it may be limited by surge?

The potato is famously mismatched for an RB25 unless you really only want to have what you have now (which is a responsive street car that falls off at the top end). It might make a bit more power than it does now (given an ECU, some more boost, and possibly the E85), but the back end is really a restriction to how far you can go. You should just search on these forums for the many many posts on what it is good for. A street turbo that boosts fast, but not a high power turbo. Keep in mind that it is half of an (upgraded) twin system used on GTRs....basically the same engine, but only half the turbo.

E85 will certainly help the chokey rear end because it reduces exhaust temps.

1 hour ago, benl1981 said:

I guess the decision of whether to go nistune or powerfc comes down the above. As if e85, then nistune would be better. Is anyone running flex fuel?

If you want E85 only, the PFC is the easier option, as you just buy it and plug it in. It can't do flex, but you don't have to source an RB20/VG30 ECU, do the extra wiring, etc.

If you want flex, your only choice (of the 2 options) is Nistune. Yes, lots of people are running flex off of suitably feature packed Nistune ECUs.

1 hour ago, benl1981 said:

I like the powerfc as I can install the new injectors and easily trim it all and drive to the tuner whereas nistune you need to buy the cable etc 

As if you would not buy a bloody Consult cable and a Nistune license if you were going Nistune!!!!! Would anyone actually consider living without it?

1 hour ago, benl1981 said:

i have a z32 ecu but I see on the nistune website it’s not recommended, they recommend the r32 Ecu for the base of the nistune. Anyone had experience with the z32 or r32 computer in the R33gtst?

Many people have experience with both. It is very clear that the Z32 ECU is not a great choice. It works, but it is just not quite right in a number of ways. The R32 ECU can now be made to do absolutely everything that is needed for an RB25, and  so is the clear standout Nistune option.

1 hour ago, benl1981 said:

Is e85 worth it for small turbos

Yes, but I would not go to the expense of setting up for E85 for a small turbo application. The returns will be too small to justify the cost. You want more power? Put on a bigger turbo.

 

Edited May 12, 2019 by GTSBoy

[benl1981]

Thanks for all that! Some things to certainly consider..

I’ve heard some rb25 owners quite happy with a hks2530 which is a similar turbo. 

I understand it’s small but thought for the 2000rpm -5500 or 6000rpm range this might be worth a shot to see if I’m happy with it as it should give great response, making around 18psi by 3000rpm (about 500 or 800rpm better than a gcg or hyper fear) 

I have the 555cc injectors already. 

Maybe e85 wouldn’t be worth it for this power level. I’ll give it some thought as I’d prefer not to change turbos, just wind this up safely by adding the computer, injectors and afm.