LS3 Engine Build Question

[dirtybird]

I was reading an article in Engine Masters magazine on a LS3 build that AFR did. If anyone read the same article, do you know if you would get the same results from a LQ4 build?

[JayR]

This is a better question for www.LS1Tech.com as there are some major league LS guru/geeks there but off the top of my head, while the bore x stroke is close, the compression ratio isn't and neither is the intake. Not sure what mods they did and if they swapped pistons and intake, it's moot. All the LS motors are killer and you can make 450 reliable hp falling off a log with one but you're a ways ahead starting with a car motor unless you're tearing it all the way down and getting an aftermarket intake and accessory drive.

[Paladin]

why bother? Just get the hotcam version ls3 crate motor and be done. Hotrod magazine tested like 9 gm crate motors in the same 69 chevelle about a year ago. With the ls3 (turbo 350 trans) the chevelle ran like 11.30's. With the lS7 (dry sump and all) it ran 10.75's. The ls7 costs more than double teh lS3 so how bad do you want that 1/2 sec 1/4 mile??

The LS3 at scoggin dickey is like $8000. How can you GM guys go wrong?? Its unbeatable value.

[realcoray]

Originally Posted by dirtybird

I was reading an article in Engine Masters magazine on a LS3 build that AFR did. If anyone read the same article, do you know if you would get the same results from a LQ4 build?

I am not familliar with that build but LQ4+L92 heads+cam = 550hp. One of the magazines did a build like this for under 3500$ I believe.

About anything you can do with a LS3 you should be able to do with a LQ4.

[tiznodd]

The main difference between the LQ4 and LS3 is going to be the aluminum block. It's about an 80lb difference. Otherwise, with LS3 heads and an intake on the LQ4, you would be close in terms of power. A used cam would wake things up quite a bit too. 02-04 Z06 cams can be had for $100 these days. The compression would be the main difference at this point, more so than the .2 in displacement.

LQ4s are most popular with the forced induction guys because they are 9.4:1 compression, and seem to hold up well. If its a pre 2005, the rods are typically the first thing to go. People start bending them in the 750hp range. On the 2005+ they received the LS2 style rods and seem to hold up better. If spinning past 6500, rod bolts are a necessary upgrade as well.