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ATR45. So a copy of a 3582 xr6turbo. Slightly smaller than a Garret 3582.

Internal gate. Stock manifold position

lol dam 400kw stealth, how does that even fit low mount.

Not yet Stao, the engine is still not taking timing, working through the list of culprits but Trent suspects an injector might be blocked partially. Everything else has been checked it seems.

I was a little worried it might have RB25 pistons, not RB25neo, but he tells me he ordered them from CP himself directly. Still, it seems to be the most likely cause to me, if all else fails.

The compression test came up 175 across the board which seems normal, but no.3 plug was definitely a different color, looked a little oily.

If it was just high compression the ethanol would have helped more I would have thought. Something is definitely up with it, knocking at 10 degrees isn't normal, unless you are turbocharging a KIA. :P

hahahahaha. No man. KIA's taking 15 degrees happily.

Well RB25det pistons are lower in compression to Neo pistons any way. Should have helped in knocking prevention. hopefully the engine is all good.

That's not how it works from what I have read, the neo head has a completely different combustion shape and will bump the compression sky high apparently.

The engine seems strong, and the torque graph was shooting skyward at an insane rate when I left, hopefully it's sorted soon before he burns the car. :P

Haha yeah fingers crossed just a failed injector

Pistons were a custom order through CP Pistons USA via High Octane Racing here. As no one keeps Neo pistons in stock

Picture of piston

24639_635744529773243_1073374748_n.jpg

No it works the other way around , Neo 25Ts have a lower flatter piston crown to maintain the same 9.0:1 static CR with a smaller volume combustion chamber .

The R33 25Ts have a higher raised piston to get static 9.0:1 with a larger volume chamber .

So in theory if you put a Neo head on a 33 engine the CR is higher than a std 33 . Stick a 33 head on a Neo short block and the CR is lower than a std Neo .

Smaller chamber + flatter piston is the better std system , less chamber surface area to absorb combustion heat and 4 valve engines breathe better with flatter pistons .

If you remember high comp pistons in hemispherical (Hemi) chamber engines you know about the great chunk of piston partially obstructing flow between the valves , it has to be this way because the chamber volume is so big .

Aside from more valve area without big heavy valves part of the pent roof 4 valve chambers advantage is compact chambers so you can get CRs up without high piston crowns .

I'd be comparing the pic of that piston with pics of std 33 and Neo pistons .

A .

That's what I was led to believe, so 33 pistons in a 34 neo would raise the compression by a substantial amount I would guess...

*Goes to Google image search. :P

Can confirm - RB25/26 Pistons will result in a HIGH compression ratio on a neo.

Source: my rb29 stroker kit with compatible pistons. (they aren't)

Also good to see the results of the ATR, given I was going to try something almost identical, (or a SS4-5 compressor) and 30psi.

If my car stops exploding.

I'd be comparing the pic of that piston with pics of std 33 and Neo pistons .

A .

That's what I was led to believe, so 33 pistons in a 34 neo would raise the compression by a substantial amount I would guess...

*Goes to Google image search. :P

Definately a Neo Piston.

This is a Neo piston from my old stock engine

1620354_793268280687533_1972113988_n.jpg

Stock Rb25det piston from google

PIC01403.jpg

Isn't everyone over east? :P

Stao only uses one casting of .82 internal gate housing for skylines as far as I know, I have asked him for an external housing a few times but it would obviously blow the cost out, as he is tooled up to cnc the internal. I can weld a gate to the housing easily as I have a jig and know where the gate will clear. You would need to organise your own screamer/plumb back pipe locally.

I have to jig up a stock manifold for a suitable gate position still, so I can't really make one until I have an rb25 on the hoist, and a spare manifold. I was hoping to get over to Stao's to check his out, but he is the other side of the city, and we are both too busy atm. Hopefully I could sell it as a kit eventually with the gate and screamer pipe, but is there much of a demand for this setup? I would need to set up a cash back on return system for the old stock manifolds.

Welding off the housing would be best for shipping purposes obviously, and there are so many cheap options out there for housings now, like the stainless Vband Tial copies I use on my car, which make turbo/exhaust swaps so easy compared to the 6 bolt Nissan.

Why u make so hard to choose!

I may just need to go of the housing for now then if its to involved atm to get done on the Stock manifold.

I personally want it because ill be keeping Low mount on my car and dont want the bling of top mount.

Could the below be done if Gate on manifold is to hard.

If i send the turbo to Stao to upgrade to SS2 and he can send to you, you can then put Gate on housing and weld internal.

( Stao can keep internal actuator as a present? )

On a crappy tight schedule aswell because of racewars :(

But i do still have till about 30th March.

Yes Jarod, PM me about it if you like. We have done that recently and it worked quickly, other than shipping times... it isn't much work for me. He likes to check them after welding I think, just to make sure, but the last one was fine I assume Stao?

I would also need the gate, Vband preferably. Do you have a local fabricator that can do the screamer?

Yes Jarod, PM me about it if you like. We have done that recently and it worked quickly, other than shipping times... it isn't much work for me. He likes to check them after welding I think, just to make sure, but the last one was fine I assume Stao?

I would also need the gate, Vband preferably. Do you have a local fabricator that can do the screamer?

I'm still waiting from Stao to send me back the housing, I was hoping to fit the turbo up this long weekend and send it to the exhaust shop during the week :(

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