LQ9 vs LQ4

[SDRacing]

Hey guys, just curious which engine would be best for turbo setup. I would like to get close to 500 hp to compete with the SRT10 . Engine is going in a 2003 reg cab 4.3 5spd.

Could you tell me what the main difference is in the two? cam/heads?

many thx,

Shane

[DBYRD]

<div class='quotetop'>QUOTE(SDRacing &#064; Jun 27 2006, 11&#58;38 PM) [snapback]56491[/snapback]</div>

Hey guys, just curious which engine would be best for turbo setup. I would like to get close to 500 hp to compete with the SRT10 . Engine is going in a 2003 reg cab 4.3 5spd.

Could you tell me what the main difference is in the two? cam/heads?

many thx,

Shane
[/b]

difference is compression ratio, the lq4 is a lower compression version of the lq9. from what everyone has said on other forums on here, the lq4 has different pistons, and since it runs at a lower comp. ratio could handle more boost. however the lq9 comes with more horsepower from the factory. ud have to weigh HP diff. that comes stock versus how much the boost will add because of the lower PSI ud have to run. LQ4=300-325 HP depending on air filter setup. lq9 = around 345 horses stock. anyone else wanna add info im missing???

[RedHeartbeat]

What kind of budget are you working with?

[Tim Z]

i heard the rods are of slightly different strength between the two, but GM usually has rotating assemblys that can handle some high H.P.#&#39;s Just swap out the pistons for some forged ones and youll be good to goon either block you buy.

[SDRacing]

<div class='quotetop'>QUOTE(RedHeartbeat &#064; Jun 28 2006, 12&#58;31 AM) [snapback]56497[/snapback]</div>

What kind of budget are you working with?
[/b]

Im going to be starting with about 8g. I think the LQ9 grabbed my attention more than the LQ4 because of the stock hp. I basically wanted to get close to 450-500 hp, and be somewhat reliable, ahem .

As time goes on, I could add more to it as the money trickles in...as long as momma dont find out&#33;&#33;

[Jamest]

I RUN A STOCK LQ4 ON 10 PSI AND I THINK I AM IN THE HP RANGE AT THE CRANK. AT THE WHEELS IT WAS 340 HP 400 TQ AT ONLY 5.5 PSI. I HAVEN&#39;T HAD IT DYNOED YET AT 10 PSI, BUT I CAN TELL YOU BY THE SEAT OF MY PANTS ITS A LOT FASTER. THE LQ4 IS A CHEAPER ROUTE JUST ADD STRONGER PISTONS AND A GOOD CAM AND YOUR GOOD TO GO.

JAMEST

[RedHeartbeat]

Hmmm...8K...what can we order for that? How about an LQ4 with forged pistons, an STS turbo kit, an air to air intercooler and 42 lb injectors? Some guys are reporting over 600 HP in their trucks with the upgraded turbo. I&#39;d get the electronic boost control and have some fun with it. Be sure to get Allen or STS to tune the PCM.

[8ty8 LS1]

<div class='quotetop'>QUOTE(RedHeartbeat &#064; Jun 29 2006, 10&#58;21 AM) [snapback]56642[/snapback]</div>

Hmmm...8K...what can we order for that? How about an LQ4 with forged pistons, an STS turbo kit, an air to air intercooler and 42 lb injectors? Some guys are reporting over 600 HP in their trucks with the upgraded turbo. I&#39;d get the electronic boost control and have some fun with it. Be sure to get Allen or STS to tune the PCM.
[/b]

yeah, but with the LQ9 500rwhp would be easy to hit going NA instead of boosting it...why boost when you can achieve without it?

[RedHeartbeat]

Well, name the parts to achieve 500 RWHP naturally aspirated. 408 shortblock, ARP225 mongoose heads ported and polished, long tube headers, Victor Jr intake, Fuel rails, 60# injectors, fuel elbow, throttle body, external fuel pump(aeromotive type), electric street model water pump....what am I missing here?

What would the dollar figures be to buy all that?

[8ty8 LS1]

<div class='quotetop'>QUOTE(RedHeartbeat &#064; Jul 4 2006, 01&#58;06 PM) [snapback]57124[/snapback]</div>

Well, name the parts to achieve 500 RWHP naturally aspirated. 408 shortblock, ARP225 mongoose heads ported and polished, long tube headers, Victor Jr intake, Fuel rails, 60# injectors, fuel elbow, throttle body, external fuel pump(aeromotive type), electric street model water pump....what am I missing here?

What would the dollar figures be to buy all that?
[/b]

i would assume that you wouldn&#39;t need a 408 shortblock at all...on the stock lq9 i was thinking a nice heads/cam/intake package will get ya really close...(within 15 hp) the 225cc AFR heads, a FAST or LS6 intake, a custom cam, and a really good street tune...i&#39;ve seen it done on stock displacement LS1&#39;s alreayd, and figured it would be just as easy, if not easier, with the larger displacement of the LQ9...