PDA

View Full Version : How accurate does this LSX buildup seem? DD2000 says...



Zedzag
09-14-2005, 06:41 PM
I'm building an LQ4 6.0 for my 81Z on a budget and was playing around with desktop dyno 2000. I'm curious if the numbers are out to lunch or what. It's a 2001 6.0 so it has the 317 LS6 style heads and I used an airflow file found on LS1 Tech and downloaded it to the custom head airflow. Here's the whole combo:

2001 lQ4 6.0, 4.0 in bore/3.622 stroke (stock)...that 364.1 C.I.
Milled 317 heads(.020), stock valves at 2.00/1.55 (downloaded head flow file)
Compression should be right around 9.75 :1 (stock is 9.4 unmilled)
700 cfm holley carb, edelbrock single plane vic jr. LSX manifold.
1 5/8 full length headers, 3" ultraflow welded mufflers.
Crane cam - 228/232 @ .050, .600/.600 lift

DD2000 says 522hp/469tq. A good friend of mine built a 355sbc and flywheel dynoed this engine and DD2000 was within 5hp/5tq.

I have no idea how accurate the head flow file could be but it doesn't look far-fetched. All cam timing events are off crane's website. I was hoping for MAYBE 475 horse.

Anyone with LSX experience wanna chime in? Thoughts? Or is it all a big dream LOL.

Ralph LoGrasso
09-14-2005, 06:45 PM
Just going on what others have made in the past, I would say that those numbers aren't too far fetched. I haven't seen many carb'd LSX numbers, though. I would think with that size cam, you should be able to hit your 475hp goal. You could always go a little bigger on the cam, if you haven't bought it yet.

The only thing I would do is go with slightly larger primaries. 1 5/8" is going to choke that motor a bit. Most all LSX LTs (for 4th gens) are 1 3/4". Most guys with bigger cubes, or FI motors go with 1 3/4" stepped to 1 7/8". I'm just basing this off of what I've seen, and read though.

WS6
09-14-2005, 07:38 PM
is this flywheel power? if so the numbers arent far off for an EFI LS motor. i too have no experience with the carbed ones. they should when tuned correctly be pretty damn close in power though.

id go with better headers and a slightly bigger cam as well. especially if this is nto daily driven. were the head flow numbers for ported heads? if not theres more power to be had there.

Zedzag
09-14-2005, 08:24 PM
Thanks for the responses guys! The head flow numbers were for stock un-ported heads which is what I'm using for the time being. The flow numbers were 240/176 @ .600 lift.

As for the headers, I bought these for cheap off of a guy who already did an LS1 swap into a 2nd gen camaro. I'll eventually go with a 1 3/4" header but these were too good to pass up.

The cam was chosen because I don't want to spin this thing past 6300 to make power, I'd rather have more torque. It'll be neat to see how much power it makes while being so mild.

Rybar
09-15-2005, 09:48 AM
Hey Mike....I think this motor combo will be quicker in a 1st Gen. :idea:

Zedzag
09-15-2005, 04:09 PM
Hey Mike....I think this motor combo will be quicker in a 1st Gen. :idea:I bet you're right! Just have to find a decent one for the right price. Anyone have one for sale LOL.