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I am going to start a motor build after christmas, I plan on spending about 3-4 years building up a Rb25 from scratch, I want to aim for 500hp, I know I could do this easily with a Rb30 or a 26 but I dont want one of those.

after its built I want to drop it into a series 2 R33 but if a 34 comes down enough in price I might put it in that.

so yeah, couple of questions.

Any particular Rb25 motor I should be buying as in will a R33 RB25 bolt straight into a R34 if I go down that path?

and is 500hp reachable with a 25

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An RB25 will support 500hp with the right supporting mods.

What is the budget for the build?

A good starting point would be a NEO engine as these engines come with GTR rods stock plus the head is similar to a GTR with solid lifters ect ect

Then all you need is forged pistons, bearings, gaskets, (cams), good inlet and exhaust manifold and ofcoarse a turbo to suit.

This is assuming you already have things like ECU, bigger injectors, fuel pump, cooler, exhaust to suit ect ect

OR

You could go all out and upgrade everything.

It all comes down to your wallet in the end,as this will determine how far and how serious you are willing to go.

You must have a clear goal and think things through carefully as you dont want to be doing things twice.

There is some info in my rebuild thread that you might find helpful.

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I am going to start a motor build after christmas, I plan on spending about 3-4 years building up a Rb25 from scratch

3-4 years?? why so long?

I want to aim for 500hp, I know I could do this easily with a Rb30 or a 26 but I dont want one of those.

Why is this?

after its built I want to drop it into a series 2 R33 but if a 34 comes down enough in price I might put it in that.

Wait are you building an engine for a car you don't have?

so yeah, couple of questions.

Any particular Rb25 motor I should be buying as in will a R33 RB25 bolt straight into a R34 if I go down that path?

and is 500hp reachable with a 25

to me it sounds like your dreaming.....

is there a particular reason you want 500hp? a 300hp car would be way more fun on the street.

alot of people go after big power and when they get it after many $$$$ they realize its useless unless you go to the track......

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Iv had 2 quick 32 skylines & allways wanted more power, In the last month or two I have sold up all my cars so I can put some money away against some debt and buy a house. After I have a house I can then buy another skyline and i allready have a good motor to dump right in where as if I buy a car now i will be paying for a car I wont get to drive for a while.

I want to build somthing I can be proud of and to aid motorvation to others. The reason I will stretch it over 3-4 years is so that It doesnt hurt my wallet constantly, I can gradually build on it and take my time. I mean after inlet manifold, rail, injectors, cams, pistons, rods, exhaust manifold, turbo, clutch, valve springs will be alot of money straight up to lay on the table.

I want to build something that will be reliable for the power as well. Iv grown up with a car in the family that I was basically scared to even breath on and I want somthing that I can be as proud with. Not to mention I work at a place where I can get things done cheaply and have access to alot of gear

I just figured 500hp was a roundish number and felt sort of realistic, in the next couple of months tho I will be doing alot of research of exactly the things I am going to need to reach my goal and even if could get over it so yeh

wish me luck!

Edited by BANGN
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oh and did i mention the lag factor?

Why is an RB25 going to be laggy compared to an RB26 making the same power?

If you've got a really laggy RB25 making the same power as the RB26, then the RB25 isn't built right...

It's only a 100CC difference, not overly noticeable, at all on the street. Now compare the RB25/26 to an RB26/30 and the latter will make much more power, with the same lag...

And just remember, Lag and boost threshold are two different things... :(

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Why is an RB25 going to be laggy compared to an RB26 making the same power?

If you've got a really laggy RB25 making the same power as the RB26, then the RB25 isn't built right...

It's only a 100CC difference, not overly noticeable, at all on the street. Now compare the RB25/26 to an RB26/30 and the latter will make much more power, with the same lag...

And just remember, Lag and boost threshold are two different things... :(

exactly why i only want a 25, not as laggy as a 20 but has similar power response to a 26 with a ported head and cams.

i dont buy cars allready built, theres no appreciation in it. Id rather spend the money and gain more experience and apreciate it more and have a talking point of the car. Better to say you built it from scratch than bought it how it was.

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exactly why i only want a 25, not as laggy as a 20 but has similar power response to a 26 with a ported head and cams.

i dont buy cars allready built, theres no appreciation in it. Id rather spend the money and gain more experience and apreciate it more and have a talking point of the car. Better to say you built it from scratch than bought it how it was.

u want a 500hp + rb25.

research a car with plates "dragme". before he turned it into a insane drag car, he was making 500hp on a 25

check fast fours forums.

nuff said

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throttle butterflies...

HOLY SHIT! Ever thought of putting individual throttles on the RB25? Not like it hasn't been done before...

Oh and the butterflies won't affect LAG or the BOOST THRESHOLD between either of them if built right.

It WILL affect throttle response... These are THREE totally different things.

Edited by MBS206
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i dont buy cars allready built, theres no appreciation in it. Id rather spend the money and gain more experience and apreciate it more and have a talking point of the car. Better to say you built it from scratch than bought it how it was.

Plenty of appreciation in built cars I can assure you. You appreciate that the fact that bits that are bolt on, cost lots of money. I've appreciated them more than the ones I did myself. These cars didn't break,burn,cut or cost me like the others for the same enjoyment.

Think of it this way; buy $50k+ worth of car and bolt on bits with the forged motor in it for $20k. If you want to customise it you can flog off the parts that don't suit your taste or even swap them. You wind up spending less money.

Think of it as buying a bargain box of parts. Some you might not want but, replacing them for the bits you do sees you do that far far cheaper as a starting point than a bog stocker.

Besides, you don't get to gain much in 'experience' from building a 'bolt on' car, unless you have never used a spanner.

If you want to spend some money and gain experience then try a 'custom' or restoration job. Or if you are sticking with the Skylines invest in learning how to tune your own car. Much bigger talking point and you get some returns on the investment. Buy the o2 wideband and do some learning so you can have a go.

Custom fabrication is a 'talking point'.

The last bit about it being " better to say you built it from scratch".

Take it from me as someone who can lay claim to a few cars, you certainly don't feel better at all when you say it. :P

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True points, however i do appreciate when some one does the car up themselves, over just buying an allready modified car that has 400kw and thinks they are top shit yet knows nothing about any of the mods to the car. Not saying this is the point here, just saying i understand where BANGN is coming from.

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Whilst I like saying everything done to my car is all done in my garage, the blood sweat and tears sometimes doesn't feel worth it when shit all goes horribly wrong and there's major f'uck ups, as I find I quite often lose my focus, and interest for a while...

Only right now, as I'm getting things back together am I starting to be slightly happy... Although it's still stressing me money wise that I may not quite finish everything when I want too...

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piece of piss to put it bluntly.

you'll need forged rods, pistons, big port work, o/s valves, poncams, inlet manifold, gt35r with a decent manifold (6boost is the best), radiator and oil cooler to keep it alive, jun oil pump and oil system mods, fuel system thats up to the task.

or in money terms around 25k

finaltune001vw9.th.jpgfinaltune002lk0.th.jpg

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