Rb24

[Clint32]

I was reading the new HPI mag and read something about building a 2.4 ltr RB20, it said you use a gtr crank and rods with 4AGZE pistons.

Anyone built/heard of one locally. For the price of a stuffed rb20 it would be as cheap as buying a rb25 probably with something a little different.

[meggala]

my site has info on the rb engine page

[Clint32]

thanks, may have to look into it a little further.

[StraightSix]

The only way I've heard of to get a 2.4 is to use the Jun (?) stroker crank. If this works would be very interesting, keep us updated.

J

[meggala]

ok I have heard of

rb 2.2, = tomei larger pistons only

2.3 bigger pistons 81-81 mm with rb25 crank and rods

2.4 with the tomei pistons and rb26 crank and rods there is machinig requiered but not sure what

2.45 special hks cranks rods etc and dispalyed on my site

do a search on the sdu foums it has been disussed heaps personally I would only do the tomei pistons or copies 82 mm cause I know some one who made around 600 with this combo.

and decided againt the 2.4 kit cause and rb 25/26 was chaeper this was in japan

meggala

[Guest Works Auto]

Guys im in the process of building a RB24 for my 32 as yet ive only got the 26 crank and rods havent yet sussed out what im gonna do for pistolas but my mechanic says he has it sorted so we will just have to wait an see what goes.

Im nearly finnished my upright manifolds for the twin TBO's and the 100mm bar n plate core going into my standard GTR cooler along with the custom plenum with 76mm throtle body, GTR injectors, after market rail and GTR pump it should go a bit better than a standard RB20.

Ill post reports and pics as they are available.

Cheers

Ross

[GTS-t VSPEC]

Works Auto,

Sounds like your car will be awesome once the RB24 is finished. Who are you getting to do the work for you? What compression do the engines have once that are completed?

See'ya:burnout:

[meggala]

interesting choice the twin turbo's on the rb 2.4 I would go single personally but the setup sounds good cant wait to hear abot it when it is going

meggala

[Guest Works Auto]

Im sure you have heard of ND4SPD well he is a mate and he is doing the mechanical work as for compression well im an office jockey/salesman so id have to ask him about that so ill let u know.He also seems to think the RB20 pistolas wil fit with the 26rods and crank,.....Cant see it myself but he is the mechanic so i guess he would have a better idea than me. We got a few RB20 blocks and shit around so we will dummy together one before we do it to make sure.

[meggala]

it will go together but you wont get a big increase of capacity you really need 81 or 82 mm pistons Ihave come very close to doing this conversion. look at the tomei site as they sell pisons for the 2.4 kit

meggala

[GTS-t VSPEC]

Yeah I heard of him, didn't know he built engines. I would agree with Meggala, that to get the increase in displacement that your after you will need bigger pistons. Luckily the RB20 blocks are relatively cheap so you can do some experimenting.

See'ya:burnout:

[Warpspeed]

The main disadvantage, as I see it is the RB20 cylinder head.

You are going to be stuck with this, even after an increase in capacity, it will limit the final power potential.

The RB25 and RB26 have a far better cylinder head design, and thus a lot more potential for development. The best bang for your buck would be an RB25DET fitted with RB26 crank, rods, and pistons. This RB26DET would then take some serious bolt on external hardware without complaint.

Personally I would prefer this RB26DET combination to an RB30DET, but it depends on what you want I suppose.

[Cubes]

I remember reading some where that if you use the RB20 Pistions and RB26 crank it only strokes out to 2.1-2.2ltrs. Not much at all.

Really by the time you build the RB24 with new pistions etc the price wouldn't work out much different to a RB25.

Only advantage would be insurance and registration issues.

[rev210]

Originally posted by Works Auto

Im sure you have heard of ND4SPD well he is a mate  

Anthony is a crazy SOB:D

I'm sure he's going to build a motor that reflects his driving personality.Should be an animal:D

[Guest Boxhead]

so what are the costs of making an rb20det into an rb24det???

by the time your all said and done, maybe its cheaper if you sell your rb20 and buy an rb25???

[GTS-t VSPEC]

I think they want to do it partly for the novelty factor, but also because when you build an engine like that you have control over bore/stroke ratios, compression etc, and therefore the result can often be better than many of the more common engines around.

I think it is a good idea, but to get the capacity you will need bigger pistons. Good luck with the engine build, keep us updated with the progress, photos etc.

See'ya:burnout:

[Clint32]

Yeah it is just something different, depends on the price but you may be able to get a motor built for similar costs to an rb25(you would still need the box though) and at least you know the motor would be right and not break in a hurry if its done right.

[Doctor]

It is a great engine if you want it to rev out. Lets face it rb20s rev out much higher and better than 25s, by increasing the displacement you have better mid range and the revy top end.

I too have had serious thoughts about it, but unfortunately the RB20 is such a fussy enginem the 25 starts to look like a good investment.

[skyline33]

Originally posted by meggala

ok I have heard of

rb 2.2, = tomei larger pistons only  

2.3 bigger pistons 81-81 mm with rb25 crank and rods

2.4 with the tomei pistons and rb26 crank and rods there is machinig requiered but not sure what

 

2.45 special hks cranks rods etc and dispalyed on my site

do a search on the sdu foums it has been disussed heaps personally I would only do the tomei pistons or copies 82 mm cause I know some one who made around 600 with this combo.

and decided againt the 2.4 kit cause and rb 25/26 was chaeper this was in japan

meggala

what about a 2.8, i've seen a special edition r33 gtst series II with 2.8 litre engine????

I think the r33 is an MR

[d0p3y]

This is interesting,

RB24DETT

Very different

Looking forward to progress reports