Dart concept RB26 and/or RB30 blocks

[khezz]

Dart are releasing a brand new cast 2JZ block. Prototypes already out and about. Stronger cast material, improved cooling galleries, 4 bolt mains. Upto 88mm bore and 94mm stroke (3.4L). Generally removing any minor flaws 2JZ had. 
 

i think an RB rebirth is on the cards. A brand new redesigned block with all of the inherit problems removed. Fraction of the cost of a billet block. I’d buy one. 

[r32-25t]

Prp have been going to release one for years, still hasn’t happened.

[khezz]

My understanding is that they are talking about their own billet block. Problem is billet is bullet. Hard to dethrone a good king. As big as PRP are now, casting blocks requires a factory in it self. The energy and infrastructure requirements to cast iron are epic. Dart have seperate factories for heads, CNC work, casting etc. different animal. 

[r32-25t]

Coming from Herman himself was they were designing a cast block that will fix all the Nissans versions issues

end of the day “cast isn’t fast, kill it with billet” 😉

[Butters]

What's actually wrong with an N1 block ?  

I know PRP did a video giving them a hard time but they are a different casting, have a thicker deck. People have a lot of success with them for more than stock block power and not outright drag billet level.   

 

We seem spoilt in the RB world > No ?

600hp - new stock block - $5k 

1000hp - new n1 block - $8k 

3000hp - new billet block - $14k 

 

 Not sure I see the gap in the market, unless you want 1500-2000hp cast block ?

Edited October 8, 2022 by Butters

[r32-25t]

Cast blocks have the issue of the cradle walking and require a fair amount of work to try and rectify.

1/2in head studs are usually desired to keep the head down but the deck ends up weak and cracks.

the bores flex and end up either being oval or crack, also with core shift in the casting process you can end up with thin  spot which either makes them only good for one over bore or not good for even one

[GTSBoy]

Yes, so even if the N1 block has slightly better material, and even if it has some casting changes to improve an obvious weak spot or two, and even if they take just tiny bit more trouble in the casting process, they are/were still cast at the same plant, using tooling that has knocked out heaps of copies, on a normal mass production basis. They can only ever be a tiny bit better than the other RB blocks cast at the same place.

An aftermarket cast block is whole 'nother matter. Most of the cost to be recouped in the sell price is in the development. The extra time and effort spent on making sure that the cores are all well located, pours are done to more narrowly constrained parameters, etc etc, only adds a little cost per block. Untenable for Nissan on a mass prod line, but completely viable on an aftermarket line. Just swallow those costs and add to the sell price because they are dwarfed by the big numbers from earlier.

[joshuaho96]

1 hour ago, GTSBoy said:

Yes, so even if the N1 block has slightly better material, and even if it has some casting changes to improve an obvious weak spot or two, and even if they take just tiny bit more trouble in the casting process, they are/were still cast at the same plant, using tooling that has knocked out heaps of copies, on a normal mass production basis. They can only ever be a tiny bit better than the other RB blocks cast at the same place.

An aftermarket cast block is whole 'nother matter. Most of the cost to be recouped in the sell price is in the development. The extra time and effort spent on making sure that the cores are all well located, pours are done to more narrowly constrained parameters, etc etc, only adds a little cost per block. Untenable for Nissan on a mass prod line, but completely viable on an aftermarket line. Just swallow those costs and add to the sell price because they are dwarfed by the big numbers from earlier.

I still can't believe Nissan wants 5k USD for an N1 block now. There's no way it's 3x better than an 05U.

[r32-25t]

We used to pay 1600 brand new for an n1 block 

[GTSBoy]

42 minutes ago, r32-25t said:

We used to pay 1600 brand new for an n1 block 

And complained about it then!

[r32-25t]

15 minutes ago, GTSBoy said:

And complained about it then!

Big time and that was Aussie dollars not US

[Komdotkom]

It will be a difficult product to sell in Australia I think. The price point will have to be $6-7k and work with a wet sump, otherwise you'd just get a billet block at $13k ish. 

The RB also has a less robust crank compared to a 2J, so do you design your aftermarket block around a billet crank which doesn't have the same inherent issues as the factory crank? I'd love to see a taller deck cast block setup for a billet crank which could be purchased as a package from Dart.

[GTSBoy]

4 hours ago, Komdotkom said:

It will be a difficult product to sell in Australia I think. The price point will have to be $6-7k and work with a wet sump, otherwise you'd just get a billet block at $13k ish.

Maybe. Maybe not. For a "genuine" street car, a billet block is an unpleasantness that you'd rather not have to live with. Much easier to deal with the thermals in a cast block. So, if you want a street motor that pushes past the sensible limits of a factory block, but don't want billet, then this is the way forward. If it costs nearly as much as a billet block and offers at least as much "strength" as you need for the street motor, it doesn't really matter if it gives anything away (in the way of "strength") to the billet block. If it takes away the worry of the stock block shitting itself and spilling money all over the road, then it's all good, no?

4 hours ago, Komdotkom said:

The RB also has a less robust crank compared to a 2J, so do you design your aftermarket block around a billet crank which doesn't have the same inherent issues as the factory crank?

A very valid concern. I was thinking similar thoughts last night. Not sure what the best solution would turn out to be. Hopefully someone clever would come up with a design that allowed you to go in more than one direction. It's not really like the main bearing and crank pin dimensions are inherently a problem. Billet cranks with the same dimensions are plenty strong. So the only real question is whether you design a closed ecosystem of block and crank to do things to permanently fix the oil pump questions, or whether you leave all the options open and limit how good the best option can be. Again, like the point about the billet block - I suspect that it doesn't matter if you cannot get "the best" out of this, if what you can get is "more than sufficient" for the sort of street application that I think it would be aimed at.

 

4 hours ago, Komdotkom said:

I'd love to see a taller deck cast block setup for a billet crank which could be purchased as a package from Dart.

Yes, but in the case of RB26 blocks, only just a little bit taller. Or, at least, not as tall as the RB30 block, so that fitting it into R32 engine bays doesn't require all the usual crap. A taller than RB30 block (for RB30esque builds) is probably not required, no?

[khezz]

There are a few videos of the 2JZ about. I emailed dart to see what the cost of the 2JZ is and what the plans are around the RB block. Will post reply when/if I get one. 
 

I can not see the cast block costing any where near that of a billet. Once the process is set, casting has very little labour attached to it. Milling a billet block doesn’t really get any easier. Allot of moving parts doing allot of cutting and grinding. Lots to replace.
 

If you are investing in a new cast block, it doesn’t make sense putting a 20-30 year old crank in it. Billet cranks have come down in cost along with stroker kits. There are enough companies making them and quality of most kits is superb.

 

I think a block that can handle in that 1750-2000hp range would be perfect. You see plenty of cast 26 and 30 blocks handling upto 1500hp. Longevity is the issue. Even a 1500hp block that doesn’t need grout or sleeves is very appealing. Mine is an rb30 with grout and sleeves. I would definitely look at a new cast block for my build. 

[r32-25t]

I reckon you’ll find it’ll be sub 10k but not by a lot. 

[Komdotkom]

On 10/10/2022 at 4:02 PM, GTSBoy said:

Maybe. Maybe not. For a "genuine" street car, a billet block is an unpleasantness that you'd rather not have to live with. Much easier to deal with the thermals in a cast block. So, if you want a street motor that pushes past the sensible limits of a factory block, but don't want billet, then this is the way forward. If it costs nearly as much as a billet block and offers at least as much "strength" as you need for the street motor, it doesn't really matter if it gives anything away (in the way of "strength") to the billet block. If it takes away the worry of the stock block shitting itself and spilling money all over the road, then it's all good, no?

 

It's whether people want the bling of the billet, since you are at a similar price point you may as well go all the way.

The other real issue is the head, since everything below it is now aftermarket and optimised the limiting factor becomes the head with its 40 year old design. Someone needs to 3D print a mould for a K series with 2 extra pots on it.

 

[robbo_rb180]

33 minutes ago, Komdotkom said:

It's whether people want the bling of the billet, since you are at a similar price point you may as well go all the way.

The other real issue is the head, since everything below it is now aftermarket and optimised the limiting factor becomes the head with its 40 year old design. Someone needs to 3D print a mould for a K series with 2 extra pots on it.

 

I think theres a bit more too it than that. But swapping heads from one manufacturer has been done off the top of my head is the ford crossflow onto holden 202 as bore spacing is the same.
A new casting of the rb twin cam head would be great, solid lifter, dual VVT, quality aluminium, bigger headstud provision and with a new bottom end see rb live on like the sbc.

One reason too running a cast block over a billet is race class rules. IPRA have been stuffing the ford v8 people around allowing then not allowing certain cast blocks too.

[GTSBoy]

53 minutes ago, Komdotkom said:

It's whether people want the bling of the billet, since you are at a similar price point you may as well go all the way.

I will never understand such people. Bling doesn't help in any way.

[r32-25t]

The bling had nothing to do with my decision to run a billet block or should it be anyone’s. I spoke to a lot of people before purchasing mine including people who use them in street cars, the upgrades from the factory block were to good to ignore 

[Komdotkom]

1 hour ago, GTSBoy said:

I will never understand such people. Bling doesn't help in any way.

But you aren't a Lebanese gangster/bikie and customer of Maatouks.

2 hours ago, robbo_rb180 said:

One reason too running a cast block over a billet is race class rules. IPRA have been stuffing the ford v8 people around allowing then not allowing certain cast blocks too.

IPRA needs to be a factory block, no aftermarket blocks allowed unless your name is Ray. No special production blocks either, so you can't run a reproduction SBC block.

 

2 hours ago, robbo_rb180 said:

I think theres a bit more too it than that. But swapping heads from one manufacturer has been done off the top of my head is the ford crossflow onto holden 202 as bore spacing is the same.
 

There's a bloke who has cast a 6 cyl K series head for the old L28 from 240Z. It's $20k, but pretty awesome.