500 RWHP..not FI'd?

[Rage]

Is this possible? Just curious....I have an LS3. The magic # seems to be 500RWHP. Aside form a whipple or other FI, can a cam, tune, exhaust alone do this? Thanks!

[danhr]

just cam with no power adders.... highly unlikely unless you flycut the pistons, or someone did some funky stuff with the correction factors on a dyno.

heads and cam, and no power adders (with the rest of the bolt ons). Yes! Gets a little tricky, but it can be done. Texas Speed even has a heads/cam combination that they sell that pretty religiously gets 500+ rwhp.

And IIRC LG got their heads and cam car to get 520+ rwhp, but they flycut their pistons when they put their new heads on, b/c they milled the heads.

[Moriartii]

I wondered this also, add a cam, perhaps deck the heads (this starts to get into maybe changing out the internals), tune, exhaust.
Cheers
K

[Moriartii]

LOL, Danhr and I posted at the same time! I assume milling the heads and decking them are the same thing? By decking I am talking making the heads uniformly flat across the board and using a thinner gasket, which increases compression (I believe).

Cheers
K

[danhr]

no and yes

Decking a head is just making them straight. This is done if the head was warped. This is usually just .010".

Milling a head is doing the exact same thing except just in increase the compression ratio. Depending on how much you want to raise your compression, determines how much you mill the head.... I gained about half a point from milling my heads .020".

The problem with this is that it shows the LS3's biggest advantage/weakness:

It's big block sized intake valve.

It is obvious that the extremely large intake valve is one of the key factors on why the LS3 heads flow so much from the factory. But that comes at a price. You can only go so big, in terms of cam sizes, before you get to the point that your valve will hit your piston. This is called Piston to valve clearance. This is an extremely easy way to blow up a motor. flycutting a piston makes a little notch, in your piston, that's a little big bigger than your intake valve.... that way there's more room for your piston to valve clearance, which will allow you to run a bigger cam/mill the heads more for more compression.

And using a thinner head gasket is virtually the same thing, except that also effects your quench. and that's a whole other ball game, which i dont want to get into right now. lol

[Moriartii]

Ah thank Danhr!!! Makes sense and I follow you regarding flycutting as I have seen that just didnt realize what it was.

Rage, sorry to thread jack. I just love me some engines and have all kinds of questions.

Cheers
K

[Moriartii]

So let me sort of bring this back around to Rage's question, what is more cost effective given initial outlay of cash; doing a cam, tune, exhaust or going FI?

It would seem to me from layman's terms that a cam, tune, and exhaust would be cheaper and safer (?) if you were set for only the 500hp? Seems if you wanted more then it would become more costly.

Cheers
K

[Rage]

I appreciate the input....just curious more than anything. I have nothing against FI, just wanted to see what could be done with natural aspiration.

[Anthony @ LG Motorsports]

I have had cars run 488-498 rwhp on the LS3 cars without doing the heads, or having to fly cut the pistons.

Does it take a little bit of work? Sure it does. Is it a big cam? Yeah it could be considered a good sized cam. So please do keep that in mind and be honest with how you want the car to run.

This combo has made 490 rwhp on average....couple Vette's have done 500-504 rwhp same combo. All SAE corrected on a DynoJet.

• LG Super Pro 1 7/8" headers and LG 3" mufflers
• Cold air induction (we have used a few)
• Under drive crank pulley
• Ported throttle body
• G6X3 cam kit
• Full Tune

Couple cars have used the FAST 102 intake, while the intake didn't do much as far as power goes but the 102 mm throttle body did pick up another 8 or so to the rears and 12 ft-lbs.


This car was before the intake and throttle body

[OrangeChevyII]

Originally Posted by danhr

And IIRC LG got their heads and cam car to get 520+ rwhp, but they flycut their pistons when they put their new heads on, b/c they milled the heads.

This was my Camaro. It ended up making 536 rwhp 495 rwtq heads/cam with full boltons. heads were milled .030 to raise compression which resulted in a 15rwhp gain. If you are already replacing the heads ,flycutting the pistons for the bigger cam and extra power is well worth it.
I have a TexasSpeed heads/cam full bolton car in the shop now that makes a stout 480rwhp 440rwtq. In the next few weeks it will have a G6X3 in it to make a true year round 500rwhp.

[axis]

So the bottom line is, anything can be done if you sprinkle enough $$ on it.

[mikeSS]

Originally Posted by axis

So the bottom line is, anything can be done if you sprinkle enough $$ on it.

[danhr]

Originally Posted by axis

So the bottom line is, anything can be done if you sprinkle enough $$ on it.

horsepower is not free. it's a law of physics.