MarkusG

I used to be a Ford guy since I liked the stangs, however I've been looking at the other side of the fence and Chevy engines are looking awfully good.
So, here's your chance to convert me to a Chevy lover.

Here is the deal.

• I'm building a 1/4 race car from scratch.
• I'll try to get it passed inspections, i.e. make it road leagal but there's no way in h*ll that is happening unless I use some form of trickery.
• I'm going for the 1000bhp/2200lbs (1000kg) car thing... I like N/A engines so it'll probably need some spray to reach those numbers.
• Anywho I'm thinking LS1 or LS7 as a starting point.
• LS1 are going cheap but need some work before they can measure up to a stock LS7
• LS7 are more expensive but you get a lot for free.
• I want the engine to be as light as possible
• I want the engine to be as powerful as possible
• I know it's going to be horribly expensive but I'd still like to keep an eye on the money.

At the moment I'm not even sure about Fuel Injection or Carbed?

Is there any major difference in size between a LS1 and LS7 engine? (and weight?)

I'm a n0ob with these engines so please bear with me.

dadem0n

LS1 - 346ci (5.7L)
LS2 - 364ci (6.0L)
LS3 - 378ci (6.2L)
LS7 - 427ci (7.0L)

There's a start for you

jsteele90

iTrader: (13)

just build a 6.0L engine. you get the the stronger iron block without the $$$$$ of the ls7. but dont get me wrong if i had 13k to **** away id buy a ls7

MarkusG

Lol, thanks... I do realise the difference in volume.
You can stroke and bore a LS1 I hope? This would land you close to the LS7 volumewise.
Now, maybe I've been misinformed but aren't the LS7 supposed to have titanium valves, titatium rods, 1.8:1 rockers and all kind of goodies? It won't be cheap buying that stuff as aftermarket parts for the LS1?

Maybe I should add some more info?
I like the thought of a solid roller set-up revving to +8500rpm (maybe even higher?).

dadem0n

You aint realistically gonna be able to shoot for more than 383ci with an LS1 bore, 396ci is possible but thats a REAL big crank and a baby bore

You should be looking 400+ci if you are serious.

Here's somewhere to start looking...
https://ls1tech.com/forums/nitrous-oxide/855169-2008-official-nitrous-fast-list.html

MarkusG

I've been doing my best reading up on things (for the last couple of hours) and to be honest the more I read the more stupid I feel.
So, before I start screaming and throwing random objects about....
Let's take it from the begining.
What's the max power for the different blocks?
LS1?
LS2?
LS3?
LS7?
And if anyone knows their weight I would greatly appreciate that as well.

99blancoSS

iTrader: (115)

I'll pm you with some information.

Mr.MartyStone

iTrader: (12)

LS1/LS2/LS3 block are all within a few lbs and weigh in around 87-92 lbs. Not sure on the weight of the LS7 block but it's probably close to there. all of the blocks mentioned can do 1000bhp, but the ls2 would be the strongest case to get there and much better than the ls1 in comparison. Plus you get a 4" bore and thicker liners.

MarkusG

Ok, that's nice.
I guess the LS2 block would be my best option.
Light weight, strong and a nice price.
I could probably buy a good used engine and do the build piece by piece?
A 4.00" bore with a 4.00" stroke should yield a nice 402ci.
(4.125"x4.125" -> 441ci but that's pushing it a bit don't you think?)

Now, here's a question though? This is going to be a race engine...
How much will I be able to rev this baby? Just thinking about the short block at the moment?
For arguments sake we can assume Lunati Rotating assembly (Pro series crank, superlight H-beam rods, pro forged flat top pistons).

KCS

iTrader: (20)

Of all the factory aluminum blocks, the LS2 is my favorite. It's strong, light, and reliable.

With steel rods and a decent light weight piston you should turn 7500-8000 at best. More than that and you'd probably want a nice aluminum rod, like GRP's.

But of course, if you don't have the valvetrain and cylinder heads to support that RPM, then it's pointless.

Mr.MartyStone

iTrader: (12)

Unless you resleeve the LS2 you're not going to be able to go to a 4.125" bore, 4.005" is about the norm, and more than .020" over and you're on the edge of reliability. The 4.125" stroke can work if you don't plan on spraying. The liners of the LS2 are only 5.440" long and the ring package gets really tight usually only leaving around 1.050" CH. The ls7 has 5.9" liners (or somewhere around there) and a 4.125" bore. If you're building a big inch motor that would be your best bet. Contact Blanco99ss on here and have him spec you out something...he uses the best LS engine builder in the country.

Nate

Stang's Bane

iTrader: (22)

If you are looking for 1000 hp and want to maintain any sembalnce of being street legal, you will have to start looking at turbos/blowers. You could possibly do it with a 300-350 shot, but the turbo route would be more reliable.

The first thing I would buy is a liquid cooling setup for your credit card, any way you do it, it will be expensive.

MarkusG

KCS> 8000rpm sounds like a resonable goal for a drag engine.

Mr.MartyStone> I hear ya' 4.00" bore it is, or maybe a slight overbore if necessary. Will it be ok with a 4.00" stroke?

Stang's Bane> I know... 1000bhp is insane and probably as likely as wishing for the moon. But hey! I'll give it a go and see how far I can get.
Street legal would be something like a rev. limiter @ 4000rpm and adjusting the timing.
And yes the plastic... it's going to take a beating all right.

Qwiknotch

Yup, factory ls2 block here, lunati pro mod rotating assembly, 4in stroke, 6.125 rod and 4 inch bore. I would go carb, personally, but everyone knows blow thru's don't work.

NemeSS

iTrader: (127)

MarkusG

Qwiknotch> Cool, that's exactly what I was thinking. A carbed engine should be much easier to graft into a new host. Are you pleased with your combo?

cutlass_455

iTrader: (2)

If you got the pockets, get an LSx block (it is heavier, but its strong as hell), GM says its good for over 500cid. At 1.5 hp per cube, your looking at 750hp on the motor. Like everyone else says...gonna need some nice flowing heads, especially if you wanna go naturally aspirated and a bit of spray.

Bring the Noise

The Blocks are similar between all of the aluminum Gen III and Gen IV motors.
The main difference is the bore size and liner thickness.
You can go with a 402 short block kit from one of the many vendors for a reasonable price (SDparts, Texas Speed, LS1 Speed, SLP, etc).

A Lunati assembly would be really really nice if you can afford it (rotating assembly's kinda expensive).
An alternative would be a Callies crank & rod + Diamond piston combo.
You'll probably need to go with high compression pistons and race fuel to hit the 1000hp mark NA on a 402 (thinking 14:1).

There is still the top end to figure out...
LS1/2/6 style Cathedral heads (15 degree [stock], 12 degree [trick flow], or 11 degree [ETP/RHS]); or the square/rectangular port L92 style (15 degree); or the ETP LS7 heads for 4" bore blocks (11 degree)... A lot of choices just in heads!

Carb Manifolds are available for both the Cathedral heads as well as the L92 style heads strait from GM (I'm not sure about a LS7 Carb manifold though).

GM has a Distributor kit for the Gen III/IV motors (mounts to the front like the old Ford 5.0's).

If you go with Cathedral heads the 2 best are probably ETP and Trickflow, but thats my option though.

Cam Choice will need to match up to the heads/manifold selection.
The Cathedral heads typically like large lobes cam's and a close split.
Where the L92 style heads like a larger split with a slightly smaller lobe.

Aftermarket Roller Tip Rocker arms for the Cathedral heads are all over the place (Comp, Crane, Lunati, Yellow Terra, Jessel, etc). Aftermarket rockers for the L92 heads are more limited (currently only Yellow Terra, still waiting on the others to catch up).


Have fun with your project and welcome to the Gen III/IV GM Small block world.

Oh I would suggest that which ever head design you choose have a custom port done to them to match up to the rest of the motor for the best power option (along with the manifold).

MarkusG

Cutlass 455> I'd rather stick with the auminum blocks if possible. I realise the LSx block is a beast...

Bring the Noise> A lot of info there... When I say 1000fwhp I mean full spray going downhill with the wind in my back and the car feeling homesick.
I was thinking E85 fuel with 13:1 static compression and a custom cam.
ProSystems Carb, fully ported heads and intake manifold, 2" custom headers, solid roller set up. As for the heads... I'm totally lost and haven't got a clue? Like I said, I'm new to the Chevy world.

99blancoSS

iTrader: (115)

First you need to look at your budget. Then you can look at feasible options.