rb25det & rb26dett why convert to singel turbo? - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

deep in silvia · 10-05-2005, 09:22 PM

I just wanted to know why GTR (RB26dett) guys convert to a single turbo set up. If they are going to do that, then why not save the money a get the GTS (RB25det).

Also..... I have the Rb25det and want to know my disadvantages against a rb26dett converted to single. Yes im talking about the motor in a 240.

thanks to anyone that can help

drift freaq · 10-05-2005, 09:36 PM

RB26 was designed from the ground up as hardcore race type engine. Reason some convert is to put a huge turbo on for high horsepower, high boost, when they are not concerned as much with the bottom end power. Nissan used a twin turbo setup so as to get a real fast, lag free spool, with a good amount of power stock. The Turbos were small because of this and become inefficent at higher boost levels.
The RB25 vs the 26 is like I stated above. The 25 while being capable of high horsepower numbers is not as built stock as the 26. Think of it in terms of the 25 being a engine that Nissan built to put in several cars and the 26 being a single purpose engine. I.E. extreme high performance AWD supercar engine that was race ready and could be taken racing straight out of the box.
In that respect a RB26 will cost more to purchase and install. Converting it to single turbo does make the install process easier.
It is also heavier due to the fact of the transfer case oil pan. While you can weld plates on either side it does make the engine heavier than the 25. Hence why a lot of us opt to put in the 25. Plus the 25 is a cheaper engine to obtain as well.
I think in addressing what the 26 is I addressed your question about the disadvantages in a overall fashion.

Also if you had a RB26 in your car why wouuld you step backwards. The 26 is an absolutely sick engine.

P.S. posting from Chicago

***S14DB*** · 10-05-2005, 09:37 PM

You want to be a dyno whore.

irritatedmax · 10-05-2005, 09:59 PM

drift freaq made good points about the turbo setups. for drift, you want the low end power and less lag and the reverse for drag. i just wanted to add if you are doing the 26 swap and want switch to rear wheel drive, it is popular to mate up the 25 rwd transmission to the 26, thus you get the best of both worlds. the 25 is an awesome engine, after all it was good enough to be in the skyline.

deep in silvia · 10-05-2005, 10:39 PM

Quote:

Originally Posted by drift freaq

RB26 was designed from the ground up as hardcore race type engine. Reason some convert is to put a huge turbo on for high horsepower, high boost, when they are not concerned as much with the bottom end power. Nissan used a twin turbo setup so as to get a real fast, lag free spool, with a good amount of power stock. The Turbos were small because of this and become inefficent at higher boost levels.
The RB25 vs the 26 is like I stated above. The 25 while being capable of high horsepower numbers is not as built stock as the 26. Think of it in terms of the 25 being a engine that Nissan built to put in several cars and the 26 being a single purpose engine. I.E. extreme high performance AWD supercar engine that was race ready and could be taken racing straight out of the box.
In that respect a RB26 will cost more to purchase and install. Converting it to single turbo does make the install process easier.
It is also heavier due to the fact of the transfer case oil pan. While you can weld plates on either side it does make the engine heavier than the 25. Hence why a lot of us opt to put in the 25. Plus the 25 is a cheaper engine to obtain as well.
I think in addressing what the 26 is I addressed your question about the disadvantages in a overall fashion.

Also if you had a RB26 in your car why wouuld you step backwards. The 26 is an absolutely sick engine.

P.S. posting from Chicago

thank you drift freaq

you answered my question right on.

420sx · 10-06-2005, 12:03 AM

my buddy got rb26 in his sil80 and almost ready to roll, few more things to finish up. im trying to talk him out of going single turbo. i told him to do dual t28

TheWolf · 10-06-2005, 05:20 AM

btw the tranny syncros on rb25 trannies are the same part as z32 so one would wonder if you could do a bellhousing swap and not worry about blowing up hard to find expensive jdm trannies.

kuramaya · 10-06-2005, 05:57 AM

Very Common over here...two of my Friends with GTR's have done the swap and both run T88's Here is one of my Local Friends car, He works at the shop I get all my parts from..Single T88, RB27..

kuramaya · 10-06-2005, 06:01 AM

Quote:

Originally Posted by 420sx

my buddy got rb26 in his sil80 and almost ready to roll, few more things to finish up. im trying to talk him out of going single turbo. i told him to do dual t28

I say Twin 2530's for Drift or 2871's for power

Angel · 10-06-2005, 07:38 AM

A properly chosen single can spool just as fast if not faster than twins for a given hp level. This has been proven many times over, take a look at the 2jz's. On top of that the setup will be lighter, cheaper,more reliable and easier to troubleshoot as you only have one of everything and vastly simplified piping.

turbo_lover · 10-06-2005, 07:15 PM

A big single turbo is the way to go if you want to make REAL power. Twin turbos aren't as efficient. But as street cars go { like the red GT-R street car} , i would go with single. The majority of people do go big single depending on displacement. Big single turbo will give you more HP also than 2 turbos.

***S14DB*** · 10-06-2005, 09:02 PM

More PEAK hp. Twins should make a wider HP band. I have seen 600hp twins pwn 900hp singles. It depends on where and how you want to make your power.

Would it be cheaper, more effective to mount a 26 head on a 25 block rather than swap in a 25 oil pan and trans on a 26?

slownslurious · 10-06-2005, 09:19 PM

Yeah but most of the really (and I mean REALLY) fast drag GTRs I've seen retain twins... the veilside car, the sumo power one, that other super fast one down in AUS...

I'm not sure why... It takes some serious power to get 8 second timeslips (like 1200 hp+ I'm guessing) so maybe twins work better at that power level (not streetable).

drift freaq · 10-07-2005, 08:08 AM

Quote:

Originally Posted by S14DB

More PEAK hp. Twins should make a wider HP band. I have seen 600hp twins pwn 900hp singles. It depends on where and how you want to make your power.

Would it be cheaper, more effective to mount a 26 head on a 25 block rather than swap in a 25 oil pan and trans on a 26?

hmmmmm, never heard anybody discussing doing that one. Its a valid question but there could be some block differences. Of course it is easier to swap a tranny and a oil pan vs a head .

hehehehehhehehehe
Your engine is already out of the car to start with since your doing a conversion.
As far as Turbo setups go , it really is a matter of some opinion, on the setups of High HP cars running duals and High HP cars running Single .
Though on average, like I originally stated, answering the thread starters question, my statement stands. There is always exceptions in areas like this, does not mean they are wise or efficient . People like to do things different ways just to be different as well.

wootwoot · 10-07-2005, 09:59 AM

http://users.tpg.com.au/cobra30/twincam.htm

Nice RB hybrid..

10-05-2005, 09:22 PM	#1
deep in silvia Zilvia Member Join Date: Sep 2004 Location: BAY AREA (Santa Rosa) Age: 37 Posts: 194 Trader Rating: (1) Feedback Score: 1 reviews	rb25det & rb26dett why convert to singel turbo? I just wanted to know why GTR (RB26dett) guys convert to a single turbo set up. If they are going to do that, then why not save the money a get the GTS (RB25det). Also..... I have the Rb25det and want to know my disadvantages against a rb26dett converted to single. Yes im talking about the motor in a 240. thanks to anyone that can help

10-05-2005, 09:36 PM	#2
drift freaq R.I.P. Aya, always love Join Date: Nov 2001 Location: Los Feliz/Hollywood Posts: 18,558 Trader Rating: (215) Rides Gallery: drift freaq Feedback Score: 215 reviews	RB26 was designed from the ground up as hardcore race type engine. Reason some convert is to put a huge turbo on for high horsepower, high boost, when they are not concerned as much with the bottom end power. Nissan used a twin turbo setup so as to get a real fast, lag free spool, with a good amount of power stock. The Turbos were small because of this and become inefficent at higher boost levels. The RB25 vs the 26 is like I stated above. The 25 while being capable of high horsepower numbers is not as built stock as the 26. Think of it in terms of the 25 being a engine that Nissan built to put in several cars and the 26 being a single purpose engine. I.E. extreme high performance AWD supercar engine that was race ready and could be taken racing straight out of the box. In that respect a RB26 will cost more to purchase and install. Converting it to single turbo does make the install process easier. It is also heavier due to the fact of the transfer case oil pan. While you can weld plates on either side it does make the engine heavier than the 25. Hence why a lot of us opt to put in the 25. Plus the 25 is a cheaper engine to obtain as well. I think in addressing what the 26 is I addressed your question about the disadvantages in a overall fashion. Also if you had a RB26 in your car why wouuld you step backwards. The 26 is an absolutely sick engine. P.S. posting from Chicago __________________ "Having a lot of tracks on a song is like putting stickers on a car to get more horsepower" New Video https://www.youtube.com/watch?v=uebV1OnbRsw Buy my mounts! http://zilvia.net/f/sale-items/51531...ns-mounts.html http://zilvia.net/f/tech-talk/317539...e-mouts-6.html

10-05-2005, 09:37 PM	#3
*S14DB* AFC #1 Join Date: Oct 2003 Location: 昨晩あなたのお母さんの家 Posts: 20,181 Trader Rating: (3) Feedback Score: 3 reviews	You want to be a dyno whore. __________________ Comments should be taken as Opinions not as Statements of Fact

10-06-2005, 12:03 AM	#6
420sx Post Whore! Join Date: Jun 2004 Location: Texas Age: 38 Posts: 3,960 Trader Rating: (0) Rides Gallery: 420sx Feedback Score: 0 reviews	my buddy got rb26 in his sil80 and almost ready to roll, few more things to finish up. im trying to talk him out of going single turbo. i told him to do dual t28 __________________ hydropgrahics! ls1......

10-06-2005, 05:57 AM	#8
kuramaya Nissanaholic! Join Date: Dec 2004 Location: 沖縄 , Japan Age: 48 Posts: 1,677 Trader Rating: (1) Rides Gallery: kuramaya Feedback Score: 1 reviews	Very Common over here...two of my Friends with GTR's have done the swap and both run T88's Here is one of my Local Friends car, He works at the shop I get all my parts from..Single T88, RB27.. __________________ ZEROYON WEBSITE IS HOMO NEW SITE: blacklinux.com/innersanctum/index.php

10-05-2005, 09:59 PM	#4
irritatedmax Zilvia FREAK! Join Date: Sep 2005 Location: Ashland, NE Age: 35 Posts: 1,360 Trader Rating: (20) Feedback Score: 20 reviews	drift freaq made good points about the turbo setups. for drift, you want the low end power and less lag and the reverse for drag. i just wanted to add if you are doing the 26 swap and want switch to rear wheel drive, it is popular to mate up the 25 rwd transmission to the 26, thus you get the best of both worlds. the 25 is an awesome engine, after all it was good enough to be in the skyline.

10-06-2005, 05:20 AM	#7
TheWolf Zilvia FREAK! Join Date: Aug 2005 Location: Orange Park, FL (Jax) Posts: 1,468 Trader Rating: (0) Feedback Score: 0 reviews	btw the tranny syncros on rb25 trannies are the same part as z32 so one would wonder if you could do a bellhousing swap and not worry about blowing up hard to find expensive jdm trannies.

10-06-2005, 07:38 AM	#10
Angel Zilvia Junkie Join Date: Jan 2005 Location: Orlando Posts: 319 Trader Rating: (0) Feedback Score: 0 reviews	A properly chosen single can spool just as fast if not faster than twins for a given hp level. This has been proven many times over, take a look at the 2jz's. On top of that the setup will be lighter, cheaper,more reliable and easier to troubleshoot as you only have one of everything and vastly simplified piping. __________________ S13 redtop 2871R.64 377 rwhp 322 rwtq 11.5 @ 117

10-06-2005, 07:15 PM	#11
turbo_lover Join Date: Oct 2005 Location: 180sx lover Age: 31 Posts: 17 Trader Rating: (0) Feedback Score: 0 reviews	A big single turbo is the way to go if you want to make REAL power. Twin turbos aren't as efficient. But as street cars go { like the red GT-R street car} , i would go with single. The majority of people do go big single depending on displacement. Big single turbo will give you more HP also than 2 turbos. __________________ BOOST is BETTER! 1. Nissan 2. Honda Oh, so you hate #2?

10-06-2005, 09:02 PM	#12
*S14DB* AFC #1 Join Date: Oct 2003 Location: 昨晩あなたのお母さんの家 Posts: 20,181 Trader Rating: (3) Feedback Score: 3 reviews	More PEAK hp. Twins should make a wider HP band. I have seen 600hp twins pwn 900hp singles. It depends on where and how you want to make your power. Would it be cheaper, more effective to mount a 26 head on a 25 block rather than swap in a 25 oil pan and trans on a 26? __________________ Comments should be taken as Opinions not as Statements of Fact

10-06-2005, 09:19 PM	#13
slownslurious Zilvia Junkie Join Date: Jun 2005 Location: somewhereville Posts: 406 Trader Rating: (0) Feedback Score: 0 reviews	Yeah but most of the really (and I mean REALLY) fast drag GTRs I've seen retain twins... the veilside car, the sumo power one, that other super fast one down in AUS... I'm not sure why... It takes some serious power to get 8 second timeslips (like 1200 hp+ I'm guessing) so maybe twins work better at that power level (not streetable).

10-07-2005, 09:59 AM	#15
wootwoot Post Whore! Join Date: Jan 2004 Location: sarasota florida biatch Age: 35 Posts: 3,850 Trader Rating: (0) Feedback Score: 0 reviews	http://users.tpg.com.au/cobra30/twincam.htm Nice RB hybrid.. __________________ I'm from Florida so I'm probably a bit more strange than you

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