RB26DETT vs. RB25DET

Hello all,

I have a quick question for you all, what are the compression ratio's of the RB26DETT, and the RB25DET?

I know the heads are diffrent, but are the internals diffrent? Crank, rods, bearings water/oil pump etc?

I am looking to swap a blow stocker 240sx motor, and I am trying to decide which engine to go for, the slight diffrence in cost is no concern. Does anyone have a source that will sell RB26DETT motors with the RWD tranny?

Also, and finally,

If I decide to go with the RB25DET, I would like to do the turbo upgrade at the same time. Is there a good place to get a tubular manifold? What Turbo should I use? (I was thinking a T66, T78 )My goal is about 500 RWHP on pump gas with ethonal 50/50 injection. Can that engine handle that much power on stock internals? Best fuel solution?

Any dyno's out there of RB series powered 240's?

Rb26dett Vs. Rb25det

Rb26: Fully Counter-weighted Crank, High Volume Oil Pump, Stronger Forged Internals, High Volume Water Pump, Solid Lifter Cams.

Rb25: Forged Internals, Hydro Lifter Cams (low Rev Limit)

The Rb25 Could Push A T88 To 30psi. But The Internals Could Handle About 600-800hp Stock. The Rb26 Has Held 800hp+ Stock And Can Push The Same Size Turbo.

Thank you very much!

Does anyone know the compression ratio's?

Rb25: 9.5 To 1
Rb26: Its Either 8.5 To 1 Or 9 To 1 (can't Remember)

It Is 8.5 To 1.

WWW.MEGGALA.COM - THIS GUY HAS ALOT OF INFO ON THE RBS.

WWW.MEGGALA.COM - THIS GUY HAS ALOT OF INFO ON THE RBS.

Thank you again!

Hey Why Hide The Knowledge? Hope It Helps You Out. And If You Want Personal Opinion.... Get The Rb25 And Build The Internals Up And You Will Still Be Cheaper Than The Rb26 But Stronger.

Hey Why Hide The Knowledge? Hope It Helps You Out. And If You Want Personal Opinion.... Get The Rb25 And Build The Internals Up And You Will Still Be Cheaper Than The Rb26 But Stronger.

What a nice attitude! I'm glad you decided to join us from NICO... did you ever go with your plans of super/turbo-charging your 240?

No I Never Twin Charged The Car, BUT I Saw The Power Of The Rb Motors And Harnessed That. I'm Going To HOPEFULLY Be Building An Rb33 Here Soon If Everything In My Life Falls Back Into Place.

The Reason I Have That Attitude Is Because I Remember When I Was New To The Forums And I Knew Alot But Everyone Was Like "look At Your Post Count, Haha!" And All I Wanted To Do Was Learn More, I Was Then Subjected To The Infamous Term "search!". I Told Myself I Would Help People That I Can Because Thats What These Communities Are For. Without Mutual Help, Knowledge, And Respect These Forums Would Go No Where Fast. Anyway, Yeah I've Been On Here Before But Left To Nico Because They Have Alot More Topics Geared Towards My End Of The 240sx Spectrum, I Returned To Spread The Knowledge Of The Rb Swaps And Try And Help Inform The Misinformed.

The only thing I ask of you musicsurfman is to quit using caps at the beginning of every word....it makes you look like you're a 12 year old noob...sorry, but it does...caps missplaced always look bad...all caps, bad caps...no caps would be better than what you do...

Annoying to read and it must take quit a bit of time since you can't type at 60wpm with all that shift usage...

I Can't, At Work My Caps Is Locked And I Can't Change It. This Forum Converts All Caps To What You See. If I Could I Would, And I'm Sorry. If You Check Nico, Az240sx, Skylinesdownunder I Do The Same There And I Have A Signature Apologizing For It Also. When I Get Time I'll Do The Same Here. Once Again I'm Sorry For Any Strains Or Discomfort Caused By My Posts, I Am Expecting A New Keybaord Though Because I Had A Job Change.

Once Again Sorry,
Christian

No problem...I assumed you were doing it on purpose...didn't realize that with all the recent forum changes that it also changed that annoyance. Anyhow, I hope you get the new keyboard soon :P

Lol I've Been Waiting For A Month And A Half So Far. Here Let Me Put It In Perspective For You..... I Just Got The Phone I Ordered 4 Months Ago, Yesterday.

You guys seem to have a good knowledge of the GTRs... Do you know reputable people to rebuild my R.33s engine to spec? The reason I ask is I want to bring mine back to the US, but the engine is a little worn, and I don't know if it would pass the emissions test after rebuilt...

I Think Anyone Can Do It If You Have An Engine Manual And Get The Parts. I Know My Machine Shop Will Do It For Me If I Have The Parts Readily Available And All The Specs.

On the RB25DET, has anybody done any stroking? , or the maximum bore allowed on the block? And an idea to make rb25det easier on the the top end completely worked heads, more agressive cams titanium retainers and valves, and a decent sized turbo to keep the engine on a boil, i am trying to build a race engine, without sacrificing too much torque, with help of maybe larger displacement
"theres no replacement for displacement" except for a t66!

You Can Use The Rb26 Internals And Stroker Kits. The Maximum Bore Is The Same As The Rb26 Which Is 88mm For Safety And 89-90 Pushing The Envelope.

Hi I own a 1981 280zx TURBO...it's all stock right now. People have been saying throw in a RB motor. But the problem is I don't know which RB motor will be good for my 280zx and which tranny do I use. Because I know the skyline tranny is a 4wd and my 280zx is RWD. So what I want to know is which motor and tranny to use. And can anyone give me price range and a list of things needed for the completion of swapping the old 280zx motor with the RB motors and tranny

first of all, this thread is almost a year old, second of all. START YOUR OWN THREAD! third, read the RB Swap FAQ. oh and try a search of this forums and check NICO
and you can get an RB20 an RB25 and RB26 to run with RWD Trannys in the 240s so i imagine it would work with your car...