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Also better pics of the dyno graph:

1000229_689430967737932_1443849661_n.jpg

581486_689430971071265_1478488373_n.jpg

581678_689430964404599_613207679_n.jpg

Green is my old setup: stock engine + china manifold

Blue: Is the forged ported engine + Brae manifold

Everything else is the same

Its a normal intercooler just the attached piping is return flow

Sort like this pic I found on google

25993916.jpg

So if Scotty where to fix up some of the bends it might be better lol?

As im going to assume its the angle of the bends not the length of the pipe that might be the restriction?

Is hybrid intercoolers any good? Dont know much about them

Personally I highly doubt it has anything to do with the bend causing restriction. Mine was a pretty fkn brutal bend as well as being 2.5" piping and didn't have any issues flowing 295rwkw.

Personally I highly doubt it has anything to do with the bend causing restriction. Mine was a pretty fkn brutal bend as well as being 2.5" piping and didn't have any issues flowing 295rwkw.

Interesting!

Though 284rwkw and 295rwkw isn't much difference lol

Have there actually been results with these turbos on an RB25 making more power on straight pump gas? I've made noises about the wondering how the VNT/FNT technology would perform on pump gas when being leaned on - partly because I am curious about how exhaust manifold pressure is going to behave with what could be defined as obstructions along the flow path towards the turbine. E85 can mask some effects of soaring pressure (ie, being much more knock resistant) but with pump gas it is going to start complaining quite quickly if it is a bit excessive.


The principle behind VNT could easily be thought of as being equivalent to being variable A/R in regards to it's effect, and relies heavily on correct actuation to not become a restriction at the wrong point and also providing good spool - however how FNT has had me fascinated is that surely there is the potential that it has the net effect of providing a larger a/r that flows (and spools) like a smaller one, to some degree defeating the purpose?

I have been specifically waiting for pump gas results to see how these go and this is the first FNT I have noticed being leaned on using pump gas and the result is what I would have expected with "nozzles" angled to boost spool which don't adjust once flow requirements increase. There may be results for this setup which prove that it is fine, so I am absolutely by no means suggesting that I believe there would be an issue with it - I am just voicing an idea which hopefully can easily be proven wrong to eliminate, or otherwise provide a possible explanation.

Interesting!

Though 284rwkw and 295rwkw isn't much difference lol

That's true, though it was at ~17psi and the tuner said it still had more but he stopped there because it's a standard engine (read: he's a big softy sooky-lala)

Have there actually been results with these turbos on an RB25 making more power on straight pump gas? I've made noises about the wondering how the VNT/FNT technology would perform on pump gas when being leaned on - partly because I am curious about how exhaust manifold pressure is going to behave with what could be defined as obstructions along the flow path towards the turbine. E85 can mask some effects of soaring pressure (ie, being much more knock resistant) but with pump gas it is going to start complaining quite quickly if it is a bit excessive.

The principle behind VNT could easily be thought of as being equivalent to being variable A/R in regards to it's effect, and relies heavily on correct actuation to not become a restriction at the wrong point and also providing good spool - however how FNT has had me fascinated is that surely there is the potential that it has the net effect of providing a larger a/r that flows (and spools) like a smaller one, to some degree defeating the purpose?

I have been specifically waiting for pump gas results to see how these go and this is the first FNT I have noticed being leaned on using pump gas and the result is what I would have expected with "nozzles" angled to boost spool which don't adjust once flow requirements increase. There may be results for this setup which prove that it is fine, so I am absolutely by no means suggesting that I believe there would be an issue with it - I am just voicing an idea which hopefully can easily be proven wrong to eliminate, or otherwise provide a possible explanation.

Stao was originally doing all his testing on pump 98 man. All the FNT gear was originally produced with pump 98, and he didn't have an issue. There are a tonne of 98 based FNT results (from Stao's test car, same tuner same dyno) in the dyno thread.

See below hekkas MS Paint representation of what my bend looked like. Yes, the piping didn't even make 90 degrees before meeting the next part of the bend.

Shmf4ht.jpg

Stao was originally doing all his testing on pump 98 man. All the FNT gear was originally produced with pump 98, and he didn't have an issue. There are a tonne of 98 based FNT results (from Stao's test car, same tuner same dyno) in the dyno thread.

Thought that could be the case - any examples out of curiosity? I did a search for "FNT" and the only result that came up for me was Hanaldo's which I have the impression the entire setup has never quite delivered for him, yet?

One thing I forgot to mention

With the new engine, Trent had to take out 8 degrees of timing compared to the old engine, as any more it would be pinging too much.

Fuel used was BP 98. Filled up only a couple days before hand

Thought that could be the case - any examples out of curiosity? I did a search for "FNT" and the only result that came up for me was Hanaldo's which I have the impression the entire setup has never quite delivered for him, yet?

Almost all results pre page 43 on the dyno thread is on 98 ron, bar like 2 posts max.. Once Stao went to E85 he never wen't back.

To my understanding the turbine side of things reached a point where no changes were needed beyond housings and compressors. Thus he did a back to back with the SS2 when he went to E85 and any advancement from there can be seen as an improvement regardless of what fuel you are running.

Here is page 43 where he first changed to the current full blade SS2 on 98, that is an FNT IWG item and went 312kw:

http://www.skylinesaustralia.com/forums/topic/55845-rb25-turbo-upgrade-all-dyno-results/page-43

I am fairly sure the 312kw item is the new version.


Old version is the high/low blade 71mm compressor, like what can be found in my SS1PU. Fairly high tip height with familiar looking blade curvature.

New version Stao played with the 'full blade' design and found it to work quite well. Full blade SS2 is 74mm.

I am fairly sure the 312kw item is the new version.

Old version is the high/low blade 71mm compressor, like what can be found in my SS1PU. Fairly high tip height with familiar looking blade curvature.

So in theory the new one may be higher flowing? Here's Stao's post that made me think the 312kw was an old version http://www.skylinesaustralia.com/forums/index.php?/topic/261613-Hypergear-Hiflow-Service-Continued.#entry6948624

In the 312 result he noted it as being a prototype, which I am sure was the move to the full blade wheel. However, the older SS2 was also 300kw capable.

Time for Stao to chime in and clarify now lol

I have been specifically waiting for pump gas results to see how these go and this is the first FNT I have noticed being leaned on using pump gas and the result is what I would have expected with "nozzles" angled to boost spool which don't adjust once flow requirements increase. There may be results for this setup which prove that it is fine, so I am absolutely by no means suggesting that I believe there would be an issue with it - I am just voicing an idea which hopefully can easily be proven wrong to eliminate, or otherwise provide a possible explanation.

This is the result from the latest SS2 FNT model on pump 98, stock manifolds, internally gated as previous posted. The older version is no longer manufactured.

power.jpg

boost.jpg

I had a quick chat with Trent (tuner) about With Blah_blah's result. Apparently he pulled 8 degrees of timing out of his old map, as it some how knocked badly. Meanwhile the stock engine did not have this issue using the same turbocharger and the rest of the setup.

Reasons given by his engine builder was that because the head ports are now over sized so they flow much more then what they were standard. And the extra flow now demands for a larger rear housing. I personally do not have any experience with ported heads so I can't comment.

Well, bigger rear end is not a problem, I have them in 1.02 rear or .82 turbine housing with a bigger G4 turbine wheel.

Hmm interesting - if it were enough porting to cause that effect then that potentially means too much porting, I'd have thought! Its not miles behind in power for 8deg less timing though, at least?

It may not even be the rear housing it may be the turbo altogether is a bad match now...I mean you design your turbos to match a rb25s power zone...that is 3500-6500....he has now designed a head that is probably more suited to flow from 4000-8000 so a bigger turbo all together may be what's in order..

Will the ss2 even spin to 8k or will it drop off power too early?

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