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This is my thread for the things I find out as my engine gets rebuilt.

I blew the ringland between the 2nd and 3rd rings in no.6. All the other pistons were pitted etc.

The rods are indeed the same as GTR rods (anyone want to buy the set I bought in case they weren't :))

It appears that the head uses quite a different design than previous RB25's. More details to come.

It uses a RB26 style oil pump but retains the short drive on the crank like early RB26's and all RB25's so I'm going to try to source a Jun crank collar.

At this stage I'm thinking of 8.8:1 compression ratio to give me a bit of safety with the tune but hopefully not losing too much in the way of response or power. I've had everything from 8.2 to 9+ recommended to me which has been confusing.

Removing the engine wasn't too hard with the help of Duncan and Ed. Thanks guys.

I think that's it for now.

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Stock compression wasn't measured.

Blew it - http://www.skylinesaustralia.com/forums/in...topic=87738&hl=

Can't rely on the availability of Optimax 100 just yet.

Bass junky with the same setup to what I will have (ie cams and turbo) could only put 0.9 bar into his engine but got great power there so I thought that with a little less compression I might be able to squeeze in the extra boost to make up for lower CR plus a little more for happy days.

Some pics to come.

I spoke to GCG today about my turbo maxing out at 14 psi.

He said that he's never heard of one making that power at that boost.

He said they were most efficient at about 17 - 18 psi.

I'll get to the bottom of this. Maybe RacePace are just the worlds best tuners.......

Abobob,

Its definitely a concern, go with an 8.5:1 to be safe. :D

On that note I believe Freebaggin is still running the stock 9:1, he hasnt mentioned the use of a thicker headgasket.

He's running an internal gate .6 something GT3040R. I remember back when it was first fitted, ~270rwkw on 17psi, he has since fitted 256duration cams and cracked 300rwkw. Its not on an optimistic dyno either.

It's not a NEO. Maybe the Neo has some issues with cam timing or something silly? I'm not 100% sure on the NEO VCT, is it constantly variable or??

Edited by Cubes

I will be fitting the Tomei Tybe B Poncams which are 260 degrees both sides and 9.15 lift. This will lower my dynamic compression ratio a little and hopefully make it a little more resistant to detonation.

I don't know anything about the VCT. As for cam timing, all I know is that adjustable cam gears have been proven not to work on the NEO.

Bass - maybe GCG are making better turbos than they think because I had 228 at 0.85 bar, no cams and auto. One dyno operator reckoned that was close to 250 in a manual although I think the R34 auto seems to be a less lossy transmission than some. It makes me wonder if Sydneykids GTT had a turbo with different specs (ie GCG are doing them different nowadays) or that it had a thicker head gasket in place before he saw it because with the same cams it takes an extra 0.5 bar to make not that much extra power.

And let's not forget the reputable workshop who told me not to expect more than 220 at the limit of the turbo. Methinks some people have an agenda.

Here are some photos my engine builder sent me last night.

post-7957-1132695461.jpg

post-7957-1132695538.jpg

post-7957-1132695580.jpg

post-7957-1132695645.jpg

post-7957-1132695667.jpg

Agenda? Definently.

SK's 265rwkw figure was recorded in Shootout mode which at 250rwkw reportedly gives about 10-15 rwkw higher figure.

Until the next dyno day on a shootout dyno, I'll not know what my car makes in shootout.

I have the same cams Abo Bob.

Here's my power curve.... It's fat.

post-6399-1132702031.jpg

post-6399-1132702079.jpg

Agenda?  Definently.

SK's 265rwkw figure was recorded in Shootout mode which at 250rwkw reportedly gives about 10-15 rwkw higher figure.

Until the next dyno day on a shootout dyno, I'll not know what my car makes in shootout.

I have the same cams Abo Bob.

Here's my power curve....  It's fat.

Thats a nice curve, must be pretty damn quick on the street.

So you guys really rate the GCG hi-flow as the best option for the 34GTT? I have an auto as well and probably chasing 250rwkw for the time being. How much extra kw will this turbo give just by itself :D I'm currently on about 200 so I don't know. If it's a long way off, I might as well get a different turbo.

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