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Ok basically i have 2 options.

1: Get a standard rebuild, Inc Forged Pistons ect and seals/gaskets replaced, pumps ect.

2: Get a Complete build done, forged everything, a very strong engine.

I have to make a decison soon i am deffently getting one of the 2.

There is around a $3000 difference in price, My power aim is about 250-260rwkw i dont want more then that, Currently at 190rwkw.

Current mods are:

Front Mount Intercooler

HKS Boost Controller

SAFC-2

Boost at 12psi stock turbo

full 3 inch exhaust from turbo back + high flow cat

I am going to get the safc removed and go for either an Emanage Ultimate or a Power FC. Id like to know peoples thoughts on these, Ive read the Emanage Thread on here and im impressed with the unit and it seems a cheaper alternative to a power fc and they are readily availble. So what to choose, Do i look around for a power fc (Spend $1500 on ebay) or do i get an emanage ultimate.

Mods im planning on after the build is:

HKS GT-RS turbo kit

550cc injectors

upgraded fuel pump

Engine Management

spilitfire coilpacks

Now My question is, Giving im wanting the 250-260kw and my 2 build choices, If i go for option 1 i can get 1/2 of the mods i plan on doing after the build, where as if i choose option 2 even though it will be stonger, the $3000 more it will cost i wont be able to get the other bits for a while. Should i just get a full rebuild and wait or will a standard rebuild with Forged Pistons and a thicker head gasket do the trick?

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Mate IMO i would not get the motor built(unless it has already blown)

Your standard motor will be able to handle that power level as long as you get the injectors put in and you get it properly tuned.

Anything over 250-260 and you use the car for track days then you might consider rebuilding it.

What do you want to do with the car anyway?

Just a daily driver?

Mate IMO i would not get the motor built(unless it has already blown)

Your standard motor will be able to handle that power level as long as you get the injectors put in and you get it properly tuned.

Anything over 250-260 and you use the car for track days then you might consider rebuilding it.

What do you want to do with the car anyway?

Just a daily driver?

Yes its my daily driver. Im not chasing huge power gains hence the 250-260kw, something to have fun on the strip with and to give a squirt here and there.

It does have 163 xxx km's on it. Other then that it runs fine.

150psi across all 6 cylinders. I was going to get the rebuild for piece of mind.

You have peace of mind mate, with 250rwkw, most motors have lasted. That in itself is good enough for what your chasing.

Only thing thats killed them has beenm the following

1. Poor tuning.

2. Poor supporting mods (like shit fuel pump flow etc)

3. Poor maintainance schedule (should be serviced every 5,000kms)

4. Ignorant driver that doesnt back off if there is detonation etc

If you look after the motor that is no reason stock internals wont last at least a couple of years even with a good beating ;)

I wouldnt even bother looking at a rebuild until the thing fails on you.

And then, i would take option 1. with the addition of GTR rods

I ran over 350rwkw with just forgies, stock crank, RB26 rods.

Wasnt a problem, was driven hard for 8,000kms, drags (over 40 passes), 100's of dyno runs, heavy street duties etc.

Also, i wouldnt worry about coilpacks until your actually die.

Again, i used stock coils for my 350rwkw+ setup. Never had a problem as they were in good condition

I ran over 350rwkw with just forgies, stock crank, RB26 rods.

was driven hard for 8,000kms, drags (over 40 passes), 100's of dyno runs, heavy street duties etc.

What happened after 8000kms? Did it pop?

Or are you just currently at 8000kms?

  • 2 weeks later...

i've had a rb25 in my 31 for over 7 years now and and in the middle of rebuilding it. it has had many track and spirited driving occassions with only running 12 pound boost . Change oil every 5000ks and used good quality oil. after stripping the engine and accessing the condition of the stock bearings i found that they were on the border line of going metal to metal. So i caught it b4 things could really get expensive to build.

IMO freshen it up while its still in a serviceable condition .

my turbo was blown and is one of the reasons why im opting to build the motor.

heres my mod list

Forged Pistons

Connecting Rods

Bearings

Gasket Kit

Head Gasket

Injectors

Fuel Pump

gt35 Turbo

Braided Lines and Fitting

N1 Oil Pump

Clutch

Exhaust Manifold

External Wastegate

plenum

throttle body

CAMS

Z32 AIRFLOW

expecting about 300-350rwkw.

in all honestly i believe the above setup could support over 400rwkw, and is very expensive. so do i realli need everything on the list?

my turbo was blown and is one of the reasons why im opting to build the motor.

heres my mod list

Forged Pistons

Connecting Rods

Bearings

Gasket Kit

Head Gasket

Injectors

Fuel Pump

gt35 Turbo

Braided Lines and Fitting

N1 Oil Pump

Clutch

Exhaust Manifold

External Wastegate

plenum

throttle body

CAMS

Z32 AIRFLOW

expecting about 300-350rwkw.

in all honestly i believe the above setup could support over 400rwkw, and is very expensive. so do i realli need everything on the list?

could i ask how much this package cost/would cost??

cheers :)

List as Follows For what ive Been quoted $7500.

Forged Pistons

Billet Rods

Acl Bearings

Stud Kit

Vrs Kit

Cometic Head Gasket

Honed/bored maching obviously virtually new block/welsh plugs so on so on.

All acid bathed/linished so on so on.

A reputable shop shouldnt charge more than $1500 to do all the machining/linishing/acid so on so on but then again there are ppl out there charging up to $5000.

Getting head mild port and polish nothing to extravgent.

Hks Cams

New springs, retainers.

Already have hks cam gears.

This includes taking motor out then putting it back in and a retune when its in, then a follow up tune/check up in 1000klms.

This is for rb25det which can handle over 600hp.

Again adding to everyone else why bother with a rebuild i know of 2 other skylines with over 300rwkws which are going strong for over 2 years now will be in there soon 2 lol! Minimum cost for bottom end rebuild is around $3000-4000 Previously quoted!

Edited by INFRNT
I used RRP prices >_<

Not mates rates/discounts or ebay manifold style prices etc etc :dry:

But yeah, still not cheap even if you get some 'cheap' parts.

fair enough if ur using RRP, but i dont touch anything but genuine parts....

but i guess i am getting discounts....but like u said....it still aint cheap

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