Advice Info On Rb23/24 Engines

[32 4whore]

So the story is i have a big end bearing thats gone or busted piston or whatever it is my engine isnt liking the 3000RPM area.

So i have rung up a few places and the general picture for a fully rebuilt RB20DET is around $5000.

I continuted on to think about the cost of buying a 2nd hand imported rb20 from japan but because im very very unlucky i would most likely get a thrashed out piece of turd burger and need to replace it like my current engine.

So i put it to you guys who have way more experience in RBs then myself and my dad. Whats needed to make a RB23/24DET?

Is it just 26 crank rods and oversized pistons with bored out cylinders? Or is there more thats needed.

I currently have $3500 saved for my new engine build up. I am going to have to get some more money off those things called banks who seem to get every last cent off you before you die.

I have been quoted $4500 from Lewis Engines and $5500 at Boostworx.

IM heading towards Lewis engines as I have heard nothing but the best from them and Darren was very helpful when I rang him up.

I have been told about Nisspeed but i cannot find any info about them. I can't even find a phone number.

If anyone out there can give me a phone number for anyone that they would recommend for a full engine rebuild and or to make a RB23/24DET then please tell me.

Im guessing the 23 conversion will cost around the $5500+ mark so i no i have to save more.

Please leave any info here for either the company or 23 conversion.

Cheers

Brenton.

By the way. This will happen Jan next year.

Come on the New YR.

I gotta get my 4 whore fixed. Its killing me paying $200 a week for a brick on tyres

Edited January 29, 2007 by R32_4door_drifting

[Bl4cK32]

*INSERT RB30DET COMMENT HERE*

its seriously not worth the time or effort. Just to be difference doesnt really mean much these days. The guys who go for the rb26 to 2.7 or 2.8 sometimes regret it either due to lack of difference over the 2.6 and the cost...

If u must go this way 2.4 is with rb25 crank, rods, and them toyota pistons (i think it was 2gze ones??) that are factory forged. 2.4 is obtained with 2.6 crank, rods and pistons. U may be up for someones R&D which means $$.

Or u could buy a rb25de and slap it in using everything u have now (as well as the lower runners of the inlet as rb25de has bigger ports) and have yourself a 25 r32.

Or u could buy a $100 rb30 bottom end, slap on a rb25de head ($700) and continue to upgrade the mods as required...ie pfc, injectors, afm etc...THEN u will have a motor worthy of bragging how big your wang really is

If u really want to go for the rb30det route, pm me and i can send u the number of the guy who built Cubes' and my motors...

Edited December 13, 2006 by Bl4cK32

[32 4whore]

Cheers for the help there mate.

If u must go this way 2.4 is with rb25 crank rods, and them toyota pistons (i think it was 2gze ones??) that are factory forged. 2.4 is obtained with 2.6 crank, rods and pistons. U may be up for someones R&D which means $$.

This doesnt really make sense though.

Did you mean 2.3 is with 25 crank rods and the 2gze pistons and the 2.4 is with the 26 crank rod and pistons.

And what is R&D?????????

[Bl4cK32]

2.3 is with 25 crank, rod and them toyota pistons

2.4 is with 26 crank, rods, and pistons.

R&D - research and development -what companies charge if u are the first time they have done a project.

[Cubes]

R&D is research, the time the engine builder spends researching, measuring and playing.. i.e selecting pistons etc.

Some engine builders charge R&D some don't. The bloke who built Darrens and my own said "I'm not going to charge R&D as if I don't know something thats not your fault its mine, + R&D is over rated"

$5000... is that you supplying the motor or is it the engine builder removing and installing the motor?

A good bottom end rebuild should cost less than 3k with hypereutectic pistons installed.

We run King HP bearings, excellent bearings and do have it over acl's.

Don't use ACL hypereutectic pistons, they are apparently not crash hot.

I'm not up with it when it comes to the rb23/25 as my view is its simply not worth it as the rb20 head really is asthmatic where it requires LOTS of boost. I found the 25 head made the same power as the 20 using ~6-7psi less boost. 6-7psi less boost is considerable.

A good example of this is 88silouets rb25 head running a td06-20g. He makes ~240rwkw with 10psi.

Roy runs a rb20 head with the same turbo yet requires 20 something psi to make ~250rwkw. It shall be interesting to see how a set of 260dur cams Troy is about to install affects the boost required.

Boost threshold... 88sil's makes all its boost by 2200rpm and pulls hard to its 7200rpm rev cut. Roy's makes all its boost around 4200rpm starts pulling hard at around 2400rpm and pulls well it just over 7000rpm but can be stretched out to 8000rpm or so in the lower gears.

There really is no replacement for displacement. Engine size doesn't affect the final power just the average power. The head is what determines the final power made.

[32 4whore]

Cheers for your input cubes.

The $5000 is me using my current engine and the engine rebuilder doing all the work on my engine.

Im after a solid 250rwkws with my engine. I know i cannot make this with a rb20det without doing major work.

This is why i wanted/ am considering the 2,3 or 2,4 conversion.

My budget is what ever it will cost really. I want it done first time and done properly.

Once my engine is fixed i will convert it to manual and do everything else to it then. I just need my engine fixed asap so i can drive my car. I cant use my parents for much longer.

I want the power to be made with little boost possible. I mean within reason that is.

Can you give me the number to who u used cubes so i can give him a call and see what his thoughts are.

Cheers again for your info.

Brenton

[Cubes]

Grab the number off Bl4ck32 as his and my motors are identical and were built by the same bloke at the same time.

I don't have his number on hand.

He now has gone in to another field of work but still builds motors.

Andrew is his name.. Top bloke. Please don't mess him around as it will reflect badly on us.

If you want to make the power have the head worked on to improve its ability to flow, that includes a set of reasonable cams.

HKS for that nice lump sound, Tomei for a smooth idle.

[32 4whore]

CHeers cubes.

No way in hell would i want to mess anyone around. I have no idea really about car engines. Aircraft engines well thats another story.

But i will PM Bl4ck32 for his number.

I can feel a cool change coming for my car soon.

[Deluxe]

How does the price work if you just slap in a RB25 and sell off all your other parts??

Just wondering!

[Bl4cK32]

I basically sold all my rb20 gear that i didnt need ie gearbox, shaft etc which payed for some of the new mods that were going in, so it does work out cheaper

It depends on if u do rb25det or r32 rb25de. R33 rb25 needs wiring mods done, where the 25de slaps in.

[sinistaGTR]

just buy a rb25....

[Matty 31]

if u want a 30 engine to build off my mate has one goin cheap (literally make an offer cheap lol)

[Cubes]

Or better still scout around the little wreckers for a cheap running rb30 bottom end. They can be picked up for ~$150.

Mine was running but I chose to rebuild it even though compression was top notch.

Its what Sky30 did, ran 240rwkw for ~20k and a further 20k making slightly over 300rwkw before he decided 4wd traction was required.

[32 4whore]

Im after an engine thats not going to cause to many headaches down the track when I have to make it stock to go through regency.

What is a RB20DET good for. Im looking at a nice figure of 250rwkw and thats about it.

Nothing to big and just enough grunt to be able to hold 3rd around some tracks wen i start up drifting.

Yes I know you guys arent big fans on drifting but hey each to their own.

Arent 2.0s good for tourqe and the like.

I am just not keen on the 2.3 as some ppl have told me about the headaches with making them

[Cubes]

There's no bones about it drift is fun, track work is fun. Drift is harder on the car than track though.

In that case the 2ltr will be fine. Drift, you want a motor that is able to hold power well when over reving, the rb20 is perfect for that.

Do be sure to throw a crank collar in it though, N1 water pump to prevent cavitation at high drifto rpms and suitable oil pump with suitable pressure to hold the motor together at 8000rpm.

I would probably still look at the stroker as 250rwkw is 4500rpm pin in the seat territory.

[johan.p.g]

i dont know what diameter the pistons ud use 4 the 23/24 buit at factory diameter a 25 cranc and cons give a verry small increas in capacity and is a waist of time the 26 cranc gives a 2.1 litre

24s are built with a 25 block and a 20 crank and cons they are more rev happy than the 25 with the same tourque

this is what i plan 2 du as a 25 bottom end is only worth $100 n ill modify my current 20 head 2 fit with the crank and cons out of my donor engine il not bother with new rings or anything fancy c what the engines good 4 b4 i spend 2 much money on it im doing all the work myself so it shouldnt cost more than 200 for the build

[Cubes]

Rb20's 78mm bore and 69.7mm stroke gives 1998cc's

Rb25 crank and rods = 2162cc's

RB26 crank and rods = 2223cc's

Run 79.5mm pistons:

Rb20 - 2076cc

RB25 - 2135cc

Rb26 - 2195cc

I would probably do the rb26 rods and crank if I were building up an RB20, thats providing I was able to source a set for a reasonable price.

The rev happy isn't influenced by the stroke as the stroke we are talking is bugger all. Its the head ability to flow the bottom ends capacity at high rpm that influences its ability to rev, and don't forget a correctly sized turbo. A turbo on the 2ltr that was fine and rev happy will choke the top end on a larger capacity bottom end.

[Bl4cK32]

i found this

convert your rb20 to a rb23 2.3L

like the tomei kit

rb20= 78x69.7mm = 1998cc

rb23= 82mmx71.7 = 2271cc

simply use 4age 82mm pistons

[Leeman]

Try All make motor repairs and restoration. Their in Parafield Gdns

[Absent]

Have to add my advice on this topic

I just cant see the point of rebuilding and stroking the rb20, I love my rb20 and reckon its awesome for a 2tlr motor but at 250rwkw the gearbox becomes unreliable if it costs 5000 just to build the motor then your gonna need to upgrade ecu, turbo, intercooler, tune, etc.

Ive been searching around for a rb25det + gearbox and they cost around 3500 why not go the 25? it will be waaayyy more reliable and good for more power plus the extra torque.

Or you could do the rb30det option that cubes and bl4ck recommend, the later 2 options will be cheaper and give more power. Why go go through the drama of putting together an rb23/4?

My 2 cents