ok, time for my big project...take a guess and hopefull will have results in a few weeks. pics will be along to and maybe a write up..was gonna do this over winter, but my #7 piston said otherwise here are the specs


L92 416 block
callies crank
callies rods
Diamong pistons -7
ported L92 heads with .650 lift springs and manley valves 65cc
232/246 .595/.613 115+4 cam
6 speed
4.10 gear

 

should make about 530rwhp

 

You might hit 540+ hp if you have the L76 intake and LS2 throttle body sent to LS2 portworks like I did

What exhaust are you running???

 

I am going to say 533rwhp, dynojet

 

-3.14e^.3249

 

gonna stay with 1/3/4 headers now. switch to 1/7/8 over winter. but..

long tubes
no cats 3" x
z06 TI catback

 

your cams lift and intake duration will hold you back

go with the dual extreme springs good to .660 and get the cams lift up to .633 or so.

look at a cam thats 338 342 632 636 or something like that, but a 232 intake is what a 346 would run. you have a lot more cubes to feed.

anything with a 400 ci or greater should easily get 550 rwhp

I think a well packaged one should get 600

 

I'm running the 1 7/8 AR Headers 3" to TI catback. Will get a basic tune on Monday and dyno after about 300 miles on the new motor. Here are some pics of my 416ci build:

http://www.pbase.com/callaway/newmotor

 

if you do alot of research on the LS3/L92/L76 set up, its not the big cams that is making the power. i have called over 5 pro shops, they all recommended even smaller ones

 

Admittedly, I havn't researched cams for 400+ engines, but it's safe to error on the side of smaller for most shops. Lingenfelter recommended something like a 214/218 with .620/.625 lift for my 346.

I went with a 228 232 .625/.630 but I used 1.8 rockers to get an r lobe cam to what I wanted. Most thumb their noses at that too, but there are a lot of good cams out there that just need more lift so they have lift duration over the peak flow of the heads, so the heads have more time at their peak flow and you get a complete and full charge of air in at a high velocity.

Recommended cam sizes seem to creep up over the yrs in order to keep people coming back to buy new ones. Sort of like the high def tv's as they've gone from 720p to 1080 i to 1080p then from 1080p with 8ms response time at 60 hz, to 6ms at 80 hz, to 4ms at 120hz.....

I remember when a 224/224 .565/.565 cam was the cutting edge, then it got to 228/228 .595/.595, now a 346 runs 238+duration at .050 .650+ lift is a moderately large cam.

Did the shop explain why they recommend the desparity in the intake and exhaust duration? Typically this doesn't help make hp. When I put my cam through the engine simulator, it made less power when I went to a 228 234 vs the 228 232.

Simple engine calculation programs can help maximize the potential, but that might not be what your looking for. If it's just a daily driver with a big cubes you 'll be plenty happy where your at.

Best of luck

 

its what the intake is calling for. the L76 really chokes the air above 6300 and just drops in power. so the smaller cam is made to pick up quicker to maximize the shorter range in RPM. I talked with thunder, speed, scoggin, and a couple others that suggested this type of cam. I need the split for the retarded huge intake compaired to small exhaust valves in these heads. but they do flow 330 stock...and I even got ported ones. so soon as a good intake is available, I will prob recam. the car is used for drag racing and WILL be road racing

 

Makes sense.

Look at this manifold:

http://forum.efilive.com/attachment....4&d=1213240341


http://forum.efilive.com/attachment....5&d=1213240612

 

each runner have a TB? who makes that? and is it under 10 billion dollars?

 

each runner has a tb, but it's all sychronized by a rod down either side which is controlled by that middle cross which is in turn controlled by a servo or wire from the back of the manifold.

I think it may be out in Australia. Usually these things aren't too expensive till they get here and see what a rediculous amount people are willing to pay for a plastic piece of FAST, then it becomes 10 billion.

I recently saw Rides where they were building a propane powered lsx block nova that had a very similar intake manifold where each "horn" of the intake had a seperate filter. They kept saying "this is the first car like this in the US", but all the tech came from Australia.

A while back I got a tip that there were going to be a host of new intake manifolds released this year for the ls series engines. I'm sure that's one of the reasons we've seen the price come down a little on some of the existing units out there.

The cool thing about the propane injection, they switched to liquid propane injection (even newer tech), and just the coeff of expansion of the liquid to gas once injected in the cylinder gave the engine the equiv off 3.5lbd of boost!

Now that's taking advantage of physics.

Here is the thread on efi live, the guy that has it is the poster, topfuelman. I'm sure he can give you more detail.http://forum.efilive.com/showthread.php?t=8261&page=2