How nasty of an engine and what parts would you use to make in the low 700's at the flywheel? Possible on a LQ4 block with a 4in. crank? I'm OK with compression and big cams, needs to make max torque around 5500 and max power around 7800. Also needs to be carbureted on gas. Just looking for ideas, thanks.

 

It be way cheaper to hit that goal with a BBC, every time you say LS in front of a part it goes up in price. Sure you can hit that with LS motor NA but that is somewhere along the lines of a 10K motor.

Getting a lower compression piston and running a turbo would allow you to hit that on a LQ4. Running the engine to 7,800 is going to cost money though.

 

Just get some well ported heads ls3 heads and intake(carb intake), good compression, solid roller with good springs and you will be there. It does not have to be all that nasty, there is 64 gto with a 416 and carbed intake making 650 to the wheels with ls3 heads. That would be well over 700 on engine dyno. He road races it so the engine has to be tractable. I think he said his cam was around 250/260 for duration.

 

I already have a 402 with a solid roller set-up on some cath. ports, but the engine is apart right now so I was thinking about changing a few things around. I was maybe wanting to sell the complete top end of this motor along with all the valvetrain and just keep my short block and start over from there. It's going to take at least 700hp to be competitive (race only) with what I'm going to do with it.

 

Call Advanced Induction and have them spec something for you. Check my signature for a 700+hp build NA with a HR cam. With different heads/intake and a solid roller, you could easily hit your goal.