What mods to do on a rb25det for around 400hp?

[cosmicgate]

400whp is possible.
You will need
1. TOMEI Solid Lifters
2. TOMEI Valve Springs
3. TOMEI PROcams 260 10.25mm for intake and exhaust
4. TOMEI Cam Pulleys
5. TOMEI Shims
6. GT35R Turbo
7. JUN Oil Pump
8. ACL Bearings
9. Pistons of your choice
10. Least 550cc Injectors
11. Fuel Pump
12. Apexi PFC

Get ready 35-40k to achieve 400whp on a RB25DET. Thats what i paid and gain.
Parts may be cheap but labour to build and to convert your cyl. head to solid lifters application comes with a price.

Bump: Other minor parts will be your
Wastegate
Oil cooler
Clutch
Intercooler
Tyres

for the price of 35k-40k i think i top up abit i can slot in a 2.8L stroker kit already. Pretty much a newbie engineer here when it comes to engines but i've always wanted to do the top overhauling myself,well hell, if i screw up its only around 4-5k for a new rb25 anyway, its suffice to say, i really do enjoy building it up myself instead of sending it to the garage.unfortunately don't really have time for it and my peeps are all profesionals, they don't get the idea that its pretty fun to open up things and put `em back, they are more towards those kind of wuss that don't wanan get their hands dirty lol.

well i don't know,at the moment i'm buying just these and those parts seperately, i am really tempted to take a long leave like say 3-6 months just to do both the top and bot ends at my backyard but since this is my first ambitious quest i think i'd just take time comtemplate until i get enough ppl with the know hows to guide me around. It ain't funny when you have to open up a whole can of nuts and bolts just to get lost half way i reckon lol.(fyi i've been living somewhat a good life, i can't even change a tyre what more a god damn engine.Hmm, i resent that, so i'm here for improvement lol)

Any friendly mechanic wanna be my friend?

 

[kaminari]

Good luck!And dun forget to post ur progress here,u can do it.hee.

I`m sure Mechanic is pretty bz at their own shop.....No times to surfing~heheehe

 

[RyDeL]

What is the actual bhp of stock RB25det? anyone had tested it before?

 

[mj_23]

As the topic implies, can i get some rough idea what to completely modify for a stock rb25det in order to get around 400hp?

i currently only have 3inch piping, afm upgrade,intercooler, fuel pump and exedy single racing clutch.

For on Crank 400HP,

All u need is:
Bigger turbo
After Market ECU and a good tuner
Front Mount Intercooler
Oil Cooler
Bigger Fuel Pump
After Marke Fuel Regulator
Bigger Injector (Nismo got plug and play 480CC)
Better Air Intake
Bigger Exhaust System

That's all.

Will be good to throw in Coilover for better handling and bigger braking system (You will need it).

For On wheel 400HP
A even bigger turbo
Forge engine interior (Whatever u can find, forge it)
2.8L Stroker Kit prefered
A much stronger clutches
Even bigger Injectors and Fuel Rail (You need min 600CC injectors)

Hope these help.

Cheers
MJ

 

[Driftmeister]

I reckon if you can afford to mod ur RB25 (ER34) at a budget range of 40-50k then my advice is to sell ur car and buy the 34GTR. You get that kind of power & maybe more with just EBC, ECU and Exhaust. Your future roadmap for tuning is limitless from here...depending how deep your pocket is. Just my 2 cents comments.

Reason because i have seen many ppl done all those on RB25 yet crave for the GTR engine in the end....

 

[rajie]

just call AC Motorsport n ask him how much for GTR engine ....he did a customer car from a R33GTT converted the engine to RB26 + haltech n bigger turbine i think it cost less than 40k with labour n the whp is higher than 400bhp ..

 

[DarkChild]

400whp on just ECU, Exhaust, EBC? Those are very optimistic figures mate.

To be honest, many of the stuff you see or read, don't actually tell you the whole story. They tend to confuse BHP, Flywheel HP, Hub HP, Crank HP and WHP. They are sometimes not very honest with the kind of fuel they used during the dyno. Realibility is also a factor. Also, different dyno's read differently. You'd be disappointed when you realize you cannot achieve 400whp on just ECU, Exhaust, EBC. 400 on the engine sounds more realistic.

For example, the stock GTR injectors are abour 444cc. A rough estimate is for 1hp, you need 1cc. So technically, you will only get a maximum of 444hp on the engine. To get 400 wheel hp, your car needs to be pushing at least 500-550 hp on the engine. This is because there is power lost through spring rates and aerodynamics, rotational mass, transmission, etc..etc.. Some people say it's 20%, other say more because we are running a 4wd system. In reality, it's very hard to say as different cars put down the power differently. So, as you can see, it is not possible without fueling modifications to your car to get 400whp. Next would be your stock turbines... and the list goes on.

Truthfully, I have had quite a number of mods done to my GTR and I can honestly tell you, in my personal opinion, you'd need a lot more than just ECU, Exhaust, EBC to get 400whp. I have a Nur engine and turbines on top of that...

 

[rajie]

well said ..... NUR engine

 

[Driftmeister]

400whp on just ECU, Exhaust, EBC? Those are very optimistic figures mate.

To be honest, many of the stuff you see or read, don't actually tell you the whole story. They tend to confuse BHP, Flywheel HP, Hub HP, Crank HP and WHP. They are sometimes not very honest with the kind of fuel they used during the dyno. Realibility is also a factor. Also, different dyno's read differently. You'd be disappointed when you realize you cannot achieve 400whp on just ECU, Exhaust, EBC. 400 on the engine sounds more realistic.

For example, the stock GTR injectors are abour 444cc. A rough estimate is for 1hp, you need 1cc. So technically, you will only get a maximum of 444hp on the engine. To get 400 wheel hp, your car needs to be pushing at least 500-550 hp on the engine. This is because there is power lost through spring rates and aerodynamics, rotational mass, transmission, etc..etc.. Some people say it's 20%, other say more because we are running a 4wd system. In reality, it's very hard to say as different cars put down the power differently. So, as you can see, it is not possible without fueling modifications to your car to get 400whp. Next would be your stock turbines... and the list goes on.

Truthfully, I have had quite a number of mods done to my GTR and I can honestly tell you, in my personal opinion, you'd need a lot more than just ECU, Exhaust, EBC to get 400whp. I have a Nur engine and turbines on top of that...

Sorry my bad...should be 400ps not whp. :sleep::sleep::sleep:

 

[naklaju]

good discussion here..but why 400hp?...not 400whp...

Bump: good discussion here..but why 400hp?...not 400whp...

 

[khoyos]

400hp is so low for skylines. 400whp should be the real target hehe

 

[Driftmeister]

For 400whp then it's safe to get the Tomei Stroker parts for the RB25.

http://www.nengun.com/tomei/stroker-kit-nissan-skyline-rb25-26-28l

http://www.tomei-p.co.jp/_2003web-catalogue/e018_kisyubetsu_rb25_ae.html

 

[EVO 6]

IF YOU WANT 400 HP AT THE WHEELS..

THERE'S A LOT OF THING YOU CAN DO..
BUT THIS IS WHAT I DONE TO MY NISSAN SKYLINE R32 GTS-T
I CHANGED THE RB20 TO A RB25..

THIS IS MY MOD LIST..

1) HKS T70 TURBO

2) GREDDY TRUST INTERCOOLER

3) TURBO SMART MANIFOLD AND WASTEGATE

4) HKS THROTTLE BODY

5) HKS SILENT HI POWER CAT BACK EXHAUST

6) TRUST OIL COOLER

7) SARD RADIATOR

8) HKS SUPERSONIC BLOW OFF

9) AFTER MARKET ECU SHIP

10) GREDDY TRUST TURBO BOOST CONTROLLER

11) TRUST GREDDY OIL CATCH CAN

12) WALBRO FUEL PUMP

13) HKS SPARK PLUGS

14) HKS ADJUSTABLE CAM PULLEYS

15) HKS CAMSHAFT

16) HKS TIMING BELT

17) HOLLY FUEL PRESSURE REGULATOR

18) XTREAM FLYWHEEL

19) HKS Surge Tank

20) SARD 800CC FUEL INJECTORS

THIS MAKES ABOUT 450 HORSEPOWER AT THE WHEELS
ON 2 BAR BOOST..

 

[khoyos]

bro, no engine internal mod? my car boost 0.8bar also all 6 pistons shit themselves already. oil pump?

 

[Dr.D]

wow, 450 on wheel.. thats awesome!!! wel , i guess the internals cantake it.. i read some rb25 making 570 bhp with stock internals.. before it melted of course..hehehe.. any ways, sir driftmeister, ur hitting 400 whp already at 1.4bar.. whats ur secret? n ur Top Secret tuner..hehehe