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Na Rb25/30


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Hi all.

Im just wondering what would need to be done in order to put a rb30 bottom on my rb25de neo head. I have addressed a few points below.

The reason why i started this thread was due to; most of the other threads related to this topic were unfortunatly trolls or didnt have any information in relation to cost and power gains

I know that selling my car and getting a GTT is a better option

but im an NA fan. :D

Easy to do.

Approx cost.

Parts needed.

Raising compression if need be or the best way to raise them.

Approx power gain.

All advice would be greatly appreciated.

Cheers.

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Unless you want to spend a small fortune dont bother. Getting power out of a n/a isnt cheap.

Theres a guy on the r31 forums who had a worked n/a rb26 and spent a crap load, over 25k i think. He only got 170-180 rwkw. Considering what else you can do with that sorta money makes it a pretty stupid excercise.

Not saying it would cost anywhere near that but that just gives you an idea, it'd cost over 5k to get a decent n/a motor imo.

If you have a 34 you really need a turbo, there to heavy for n/a. Only cars close 1 tonne are good n/a.

Edited by eightsixboy
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Before you even start, I would take an NA 2JZ Supra for a drive. Similar weight, and similar performance to what you could expect from a 3L NA skyline.

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Cheers for the help guys.

These damn p plate laws are so annoying.

Although i do understand why they are in place.

looks like im stuck with a slow na r34 for another 3 years because you have to be 22 to get off your p plates now :(

FML.

Cheers.

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Cheers for the help guys.

These damn p plate laws are so annoying.

Although i do understand why they are in place.

looks like im stuck with a slow na r34 for another 3 years because you have to be 22 to get off your p plates now :(

FML.

Cheers.

you do realise that putting a rb30 bottom end into your r34 would also be illegal?

if you want something faster than your r34, get a late model commodore or falcon and put a shorter diff ratio in it. won't be quite as good on the highway as it would be with the stock ratio, but round town it will be much faster.

or a 3.5L v6 manual magna. they will do the 1/4 mile in under 15 seconds (my last one did it in 14.8 with just a catback)

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Damnit beat me to it :P

I know a way it can be done! :whistling:

But, expensive beyond your worst nightmare would be the first reason you wouldnt do it.

The second is what zebra said. Very smart move!

Third... save your money and survive your P's with the small amount of points they give you. The if you want something faster, just go and buy it once your off your P's.

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the natro ones will beat a natro skyline, but that is beside the point. the main point is that the dash looks like the cockpit of a 1950's plane that has been butchered to fit in a car.

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the natro ones will beat a natro skyline, but that is beside the point. the main point is that the dash looks like the cockpit of a 1950's plane that has been butchered to fit in a car.

My na r33 smashed my mates na supra.

Damn their interiors are so damn ugly lol

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