adillhoff

I, for one, like to do a lot of research before I get into something I don't know about. I want a nice 600+HP street car. This is my plan at least.

Here goes. Would I be wiser with a LS2 402 or LQ9(Correct me if I am wrong) 408?

I will be doing all of the work by myself, save the tuning. Where is the best place to pick up the block, pistons, rings, yadda yadda.

I would consider a pre-built shortblock, but my favorite thing about adding power is doing the work myself. That's pretty much the main reason I have bought any mod for my car so far. I love working on cars.

Is the 402 good for nitrous and boosted applications? I was thinking of a twin turbo 402 set up as my dream motor.

I would just like to learn a lot more about this so, when the time comes, I know exactly what to do and what to buy.


Cliff's Notes:
I want 600+HP N/A
402 or 408?
I want to do the work myself?
How much (estimate)?
Boost or not?

300bhp/ton

TSP have some good deals, but so do a lot of the other sponsors so I'd go speak with a few.

As for your setup, well it seems all over the show to me. 600HP are you meaning at the flywheel or the rear wheels? Because I think you'll find it very challenging to get 600rwhp and not at all easy for 600bhp SAE Net.

LS1's have been proven with a good head and cam combo with supporting mods to make ~480rwhp SAE on a Dynojet, this is about 450rwhp SAE on a Mustang Dyno. And in all means somewhere around 500-530bhp SAE Net.

This means 79rwhp per litre (450 / 5.7).

So a 6.6 litre (402ci) tuned to the same specific output (supporting mods, good heads and wild cam) should also be able to see 79rwhp per litre.

79 x 6.6 = 521rwhp SAE Mustang Dyno or 558rwhp SAE Dynojet.

This should still be streetable and running on pump fuel. So it should just nudge 600bhp SAE Net. But it will mean running a slightly better than stock SCR.

Of course you could go for a completly non streetable cam and sky high SCR and see more HP but it won't be of much use on the street.

And this is the problem, if you want boost you don't want an engine setup for n/a. A supercharger doesn't require ultra low SCR but I would guess somewhere around 9.1:1 would be ok. But this would suck as a n/a application.

If turbo you'd probably want too look at a lower SCR again and a milder cam. So n/a performance will not be anywhere near the 600bhp mark.

As for a 408ci cast or 402ci aluminium block I think it's your choice. The 408ci is cheaper and ultimatley is probably stronger but you are likely talking applications in the 1200-1500bhp area. The aluminium is lighter.

As for HP variance, well there's only 6ci in it. So that's probably only going to be around 8bhp+- difference.

adillhoff

I see. So if I chose a turbo set up to achieve 800-900 rwhp, which would you choose. The aluminum or iron?

slt200mph

iTrader: (42)

Buying all of your parts and then the machine work will cost you more than a short block from one of the vendors on here. If my memory serves me I beleive that a forged 402 short block can be had for about $3800..

300bhp/ton

For me handling is a big deal so it's a no brainer - aluminium. Less overall weight, better f/r weight distribution and most importantly lower centre of gravity.

However, if you are not worried about cornering and most is going to be strip work then the cast iron is cheaper.

adillhoff

Handling is a big issue for me which is why I am aiming towards aluminum. I really appreciate the feedback everyone. So I guess a pre-built shortblock would be cheaper? Does nobody sell bored LS2 blocks?

300bhp/ton

Not sure.

Have a word with the guys over at Texas Speed & Performance ---> They are a sponsor and have a great reputation.