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Just putting it out there, interested in hearing peoples thoughts on this. 
For a GTR with where they are going and with ‘purity’ possibly becoming more important nowadays. 
would you prefer a 26 based bottom end or a 30 based bottom end?  
and why? 
purely for discussion, let’s not go to war over this! Lol 

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For a motor that will feel better everywhere in all usage models, a 30. Every time. The only way that it is let down compared to a 26 is that elastic need for revs and the extra little buzz you get from running to 11ty rpm. But I'd rather more torque and power everywhere.

Put the 26 block in the shed for later purity restoration.

Although....in a 32, I am against the shitty mods you have to do to squeeze a 30 into the engine bay.

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3 hours ago, Stixbnr32 said:

Yeah if i was to do my build again id still go 26 block in my R32 but id prob go a nitto 2.8 stroker.

Everything fits under the bonnet and you get a decent bump inpower/torque.

I would also use a PRP brace.

THIS. I kinda regret doing a 3.2 mainly due to fitmet issues. I just hate chopping shit up, but thats just me. I'm sure when mines running it will be well worth it, but if i was to do it all again, I'd def do a high revving 500kw 2.8.

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Cheers for the responses, looks like a 26 based bottom end wins the popular vote. 
To ‘let the cat out the bag’ I’ve been considering building a bottom end and was undecided which way to go. 
My car is currently fitted with a 30 bottom end. 
anyway, the opportunity has come up to purchase a JHH built 2.7 motor, built in an N1 block with their Raceport head package. 
My reservations are, my current setup is so good, torque everywhere, good response and fast enough for me, but this set up isn’t where I’m going with the build. I want a 26 block, but I’m nervous I won’t like it compared to what I currently have. 
the struggle is real! Lol 

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1 hour ago, Predator1 said:

If you already have a 30, then stick with it. 2.7 will see a noticeable amount of lag, plus you might need a smaller turbo.

Depends on what you really want at the end of the day. How much power does your 30 make atm?

Car make 440kw on 98 @ 20psi 

and 580kw on E85 @ 32 psi 

Obviously the powerband will move up the rpm range in the 2.7, but the 2.7 will happily Rev to 9500rpm and the 3.0 is restricted to lower rpm. 

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5 hours ago, GTSBoy said:

I dunno man. You've already done what's needed to put a 30 based engine in. The damage is done, the pipework is set up.

At your power level you're really going to feel the difference if you drop 10% capacity.

That’s where I’m stuck, the 30 is in and is a great motor. Was built well, but a part of me really wants a 26. 
then on top of that, I’m nervous I’m going to be disappointed. 
AND at some point, I will be going back to a 26 block, just this opportunity has come up now and I was hoping to enjoy the current set up for a few years first. 

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23 hours ago, Predator1 said:

THIS. I kinda regret doing a 3.2 mainly due to fitmet issues. I just hate chopping shit up, but thats just me. I'm sure when mines running it will be well worth it, but if i was to do it all again, I'd def do a high revving 500kw 2.8.

This is me, if I was building a motor, then I would build a 2.7/8. The 30 was in it when I bought the car, but it’s proven to be a very good motor. So now a part of me says stuck with what you got, you know it’s good, it’s set up and it works, and the other part says, build it how you want. 
Now it seems from the responses here that most, if building from scratch, would go with a 2.7-2.8 over a 3.0/2 

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The torque of the RB30 is real. My mates 32R makes 440~awkw @ only 18psi with no timing, and that thing had virtually no lag. Even going uphill, that thing would just haul from any gear/revs. In contrast, a 2.6 or 2.7 or eve a 2.8 would see considerable lag before it starts to boogey. IMHO, stick with what you have, and enjoy life.

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Another thing, guys who have gone from a standard crank to a billet crank, how much difference does it make? I’ve read that the billet Rev much smoother/quicker and feel very sharp on the throttle? 

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11 minutes ago, Predator1 said:

The torque of the RB30 is real. My mates 32R makes 440~awkw @ only 18psi with no timing, and that thing had virtually no lag. Even going uphill, that thing would just haul from any gear/revs. In contrast, a 2.6 or 2.7 or eve a 2.8 would see considerable lag before it starts to boogey. IMHO, stick with what you have, and enjoy life.

Yeah I hear you, this is my car now, even with the 68/70, it’s on when you roll the throttle, rpm doesn’t really matter. As a street car, it’s probably as good as you’d want, but because I’m a little weird I think ‘As a GTR’ where do I want it? 
shouldnt a GTR have lag, isn’t that part of the driving experience, lol
If I do this, it won’t be one engine out and one in, it will be engine bay respray, blast and coat subframe, replace bonnet, re wire engine bay. I will bring the bay up to a standard I want it. It presents well now, but It’s no where near finished to a level I’m happy with. 
But thanks for the the input, I appreciate peoples opinions on this, helps to give perspective and give me an idea what to expect if I move forward with this. 

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