Simmed an LS7 - 32v version

[Billzilla]

Was just curious to see what numbers I could get out of such a big engine if it has decent heads fitted, and it didn't disappoint.
The green line is horsepower and the blue is torque, rpm's along the bottom.



That's with a smaller cam than they normally use (226deg @ 0.050" and 0.550" lift) and a conventional plenum-type inlet though it's got two big 75mm throttles to make sure it gets enough air. Less compression as well at 10.2:1.

Note that this is only a quick & dirty run, I might fiddle some more to smooth out the bumps and get some more grunt from it.

[Dusty]

good thing there is a 32v head in development huh

[Billzilla]

Originally Posted by Dusty

good thing there is a 32v head in development huh

I bet it's not a very good head though - I've seen so many that are designed very poorly. No doubt it'll work a lot better than the 2v version, but I hope it's done properly so it'll show what a decent head design can do.

[Billzilla]

How's this? I cranked it up a little!
The red & light-blue lines are the grunter engine, the dark blue & green are from the 'stock' engine.



827hp and 666 ft-lbs. Cam is 242° and 0.620" lift, lobe centres 106/108.

It's interesting because of a bit more compression and I actually fiddled around with the inlet & exhaust lengths to get them closer to right, there's little loss of the bottom-end grunt.

[Dusty]

put some more compression in + cam

[Billzilla]

Originally Posted by Dusty

put some more compression in + cam

It's got 11.2:1 compression - that's as high as you need or want to go on pump fuel in most countries. And because of the much better VE of the 4v heads, you don't need to run as high a compression as on a 2v engine.
Have a look at the cam specs, it's pretty big! And again you (typically) don't want or need to run as big a cam as you do on a 2v.

[Billzilla]

Originally Posted by Dusty

good thing there is a 32v head in development huh

Hope you don't mean these?

High Performance Machine Shop

They're horrible!