I think he's just interested to know what the driver's opinion is of the R1k. Could be wrong!

 

Yes but when I meant LSX I was referring generically to the engine. You could easily use an aluminum RHS block. The LS series is inherently a better engine particularly when it comes to breathing so I just would assume that the same boost in an LS would create more power than a SBC. Yes or no?

 

I was thinking I might be wrong on that. Still not sure. A billet block would be cool to have.
I guess we'd have to ask Nelson on the SBC vs LSX debate.

Here is a cool LSX he just built. 1800hp.

YouTube - ‪Mid Engine 1800 HP LSX SBC. New Beast from Tom Nelson. NRE‬‏

 

I cant decide!!!

Right now I am considering 3 options!

1. A Nelson SBC 447 pump gas warrior at 650hp.
2. A Nelson BBC 500 pump gas warrior at 750 (see more info on this engine at the bottom)
3. A Nelson SBC 427 TT at 1500+

I was really planning on a naturally aspired engine but when I see the numbers on the SBC I feel that 650 is on the lower end of what I want and a BBC feels a littel big and heavy just to get another 100hp. That leaves me right back where I started, at the V8 TT concept. However I do feel that even if a 1500+ hp engine is something I can never use in a car like this and the weight is bad for the car, I do admit that I like the idea of having that much power just because I can...

BTW, ever heard of Nelson building and flat crank engine? For that sound I would be willing to give up the crazy numbers but I am not sure if I am with the "normal" V8s...

Thoughts?

From Tom Nelson
We can build you a all aluminum Big Block Chevy no problem.I didnt no if you wanted that much power or had space limitations. I would suggest something maybe i little unconventional though because i think i high rpm bbc is really Cool and you won't need the down low torque because the cars 2200 lbs so i would suggest a building a 500 cubic inch bbc but with a huge 4.6 bore and a very short 3.76 stroke which will give you a very reliable high rpm combo for a BBC with low piston speeds and it will sound Nuts because of the whole combination! Hp would be in the 750 hp torque is 640 ft lbs range because i would mellow everything out a bit to be something you can drive anywhere 3000 miles in a short time but it would run past 7000 rpm and have that distinct BBC double hit sound.The injected version has a advantage because the intake can rotate 180 degrees which may make packaging easier for you.But can build you basically anything.
I can also build the 860 hp warrior i just felt the 500 inch would lend itself better to your application. Engine weight of the bbc is around 500 pounds sbc is around 380 pounds

 

I agree 1500hp would be awsome. But, would that even be driveable in a machine as light as your ultima? And pushing a 1500++ machine at a long time on Gumball is like asking for trouble if you ask me. I say go for a reliable NA engine. The 750hp suggestion above i think would be a perfect match!!

 

Why not take one of each?
Just kidding. I agree with the Swede above me

 

I would go with power that can be used. Otherwise imo its just wasted power and more weight due to the TT system.

 

Go with the Twin Turbo, but you still have options.
I don't know how much you know about NRE's twin turbo engines, so I will give you some information just in case. The Twin Turbo setups have what they call "Octane on Demand". They have two injectors per cylinder. One injector is pump gas, the other is race gas. On low boost settings it runs on pump gas. But when you turn up the boost to levels that require higher octane it starts injecting the race gas.

Personally I wouldn't want to go through the hassle of buying race gas and having to store it in the car and not use it often. But that is up to you.
To run Octane on Demand you have to have 2 gas tanks, one for each fuel. This is increased weight, packaging challenges, and reduces the fuel capacity of pump gas for trips(Gumball 3000).
The engine he is suggesting makes 1600hp on race gas, but still makes 1100hp on pump gas. If it was me I would run just single fuel injectors on pump gas making 1100hp.
That is (way more than)enough power for the weight of the car and you don't have to worry about race gas. 1600hp is just useless, but very, very braggable. So it depends on what you are looking for.

 

The thing about Nelson is he prides himself in building engines that make 1500+hp but are as driveable as a stock V8. They are also very reliable engines, other specs of the 427 SBC go up to 2500hp. 1600hp is pretty standard for a SBC from NRE.

 

One more suggestion. If you really want naturally aspirated engine, a better option may actually be American Speed. They are the company that produces the SBCs for Ultima. They have a 407ci that makes 800hp.

I say go all out with Twin Turbo, make it a true beast.