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HLEP!: Considering bulding a RB25DETT

Al

By Al,
in Engines & Forced Induction

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Al Grand Master

Al

Posted
Posted

Recently i have been seriously looking for a bigger turbo for my car, but wasn't too keen on the lag factor. My aim to to acheive 280-320rwkw, but i would like to keep it's drivability.

B4 i go on: i have done a comprehensive search and wasn't able to find anything on this issue, so please if you know of a thread post it up below.

For those in the know i would REALLLLLY appreciate your input and advise, i am all "ears"!

My idea is to replace my turbo and manifold with a twin turbo setup (gtr style). By using 2 smaller turbos (350hp each) this should, i think, produce about 400kw at the crank.

MODIFICATIONS (Things i know that need replacement):

-New manifold (Can a GTR manifold fit on the RB25det head?)

-Custom front pipes

-Dual oil/water cooling lines for turbos (can the original line be split into two to cool both?)

-Custom intake pipes (from filter to turbo and from turbo to fmic)

CURRENT MODS:

-Wolf 3D V4.51 R33 Plugin

-Fount Mount Intercooler

-Cold Air induction (Pod in sealed partition with 4" drain pipe feed from front bar.

-Adjustable boost

-3" hi-flow exhaust system from turbo

-H/D clutch

MODS TO BE COMPLETED WITH UPGRADE

-550cc injectors

-bosch fuel pump

-bosch fuel regulator

-Ceramic coating of all piping (ex. manifold, intercooler pipes, turbo cover, plenium, exhaust from turbo to cat., etc)

-ADJ. ex. cam gear (optional)

QUESTIONS:

-Is this project possible and financially fissable?

-Which turbo's would best do the job?

-Any other mods that you would recommend doing (cams, etc.)?

-Has this been done B4?

-How does the GTR manifold work? Does it use 3 cylinders per turbo?

-Any other information/points are most welcome.

Again, i would REALLY appreciate everyones input and like to say

THANKS in advance.

ALAN C.

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https://www.sau.com.au/forums/topic/14153-hlep-considering-bulding-a-rb25dett/
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meggala Grand Master

meggala

Posted
Posted

OK high power and lag go hand in hand un less you increase capacity sso you want 280-320 rwkw with boost down low the best way to do this is with an rb 25/30 motlowth on hearhas a similar set upto what you want and thats how he did it the twin turbo's are possible but you will still have lagg.

he is making 310-320 rwkw @ 1 bar full boost by 4 k rpm I believe

meggala

btw go to my web site and read the mods section It might help

Sydneykid Grand Master

Sydneykid

Posted
Posted

Hi Nismo_Boy, how about we cost this idea...

MODIFICATIONS

-New manifold $1200

no a GTR one won't fit.

-Custom front pipes $800

-Dual oil/water cooling lines for turbos $300

-Custom intake pipes $400

MODS TO BE COMPLETED WITH UPGRADE

-550cc injectors $800

-bosch fuel pump $500

-bosch fuel regulator $300

- Ceramic coating of all piping $700

- ADJ. ex. cam gear $250

- 2X hi flowed RB25 turbos $2200 each

- Dyno tune $400

That's a nice round $10,000 but the RB25 internals won't handle 320 rwkw, so you will need...........

- forged pistons $2000

- conrods $2200

- balance, gaskets, seals, o'ring block say $1800

- oil cooler $900

- radiator upgrade $1000

- camshafts $1600

- porting of cylinder head $700

And that totals $19,850.

When do you want to start?

Al Grand Master

Al

Posted
  • Author
Posted

THANKS FOR ALL YA INPUT GUYS!!

Looks like i need to go back to the single turbo idea, as the deal with NISMO_BOY may fall through. It was pure coinsidance that he was selling this setup at the time i posted this idea. But i consider $4000 for basically a block, manifold (modified rb26DETT) and 2 worn turbos a bit rich, not to mention risky.

But now i am back to my original delema. What turbo will best do the job and has the least lag? I am under no illusion that i will get more lag, just want the best package.

Nismo_Boy Grand Master

Nismo_Boy

Posted
Posted
Originally posted by Sydneykid

Hi Nismo_Boy, how about we cost this idea...

MODIFICATIONS  

-New manifold $1200

no a GTR one won't fit.

-Custom front pipes  $800

-Dual oil/water cooling lines for turbos $300  

-Custom intake pipes $400  

MODS TO BE COMPLETED WITH UPGRADE  

-550cc injectors $800

-bosch fuel pump $500

-bosch fuel regulator $300

- Ceramic coating of all piping $700  

- ADJ. ex. cam gear $250

- 2X hi flowed RB25 turbos $2200 each

- Dyno tune $400

That's a nice round $10,000 but the RB25 internals won't handle 320 rwkw, so you will need...........

- forged pistons $2000

- conrods $2200

- balance, gaskets, seals, o'ring block say $1800

- oil cooler $900

- radiator upgrade $1000

- camshafts $1600

- porting of cylinder head $700

And that totals $19,850.

When do you want to start?

Why would i want to start, when i can just buy the one im selling for $4k

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