Ls swap

[Big girth]

I have a lm7 with LS9 cam, 317 heads, long tube headers, and it’s carbed 750 Holley. What do y’all think the horsepower will be to the wheel.

 

[Injectedcutty]

4,200hp/3,847ft/lbs

 

[Big girth]

Do you mean 420/384

 

[motorheadmike]

Have fun: https://ls1tech.com/forums/dyno-guesses-bench-racing-forum-150/

 

[L92 OLDS]

I have a lm7 with LS9 cam, 317 heads, long tube headers, and it’s carbed 750 Holley. What do y’all think the horsepower will be to the wheel.

You're not using an ECM so you may be at a disadvantage. If your tune is spot on then my guess is 285HP / 320 Tq.

Although those 317 heads from a 6.0 have bigger valves the factory 706 heads have smaller chambers and may have been a better choice.
This overlay is from the same engine with 317's vs 306 heads.

 

[Kemper1976]

I’m not far behind guessing 275rwhp and 290rwtq.

Advance that cam 4 degrees. With the wide Lobe separation angle of 122.5 it’ll help the torque come in sooner.

 

[Big girth]

I running a msd box and the plan is to go turbo this summer.

 

[Big girth]

I want to make 400 at the wheel before turboing It. Any suggestions. And I was told I could use 1.8 rockers to help me with power.

 

[Injectedcutty]

No way you're gonna be 400 at the wheel, that's roughly 450 at the flywheel. Anubis has a 6.0L in his Cutlass and with the efi tuned he's at 420ish. Carbing an LS eliminates alot of tunability and loss of power.
The LM7 in my Cutlass has 862 heads with BTR .660 springs, a .613/.598 lift cam, stock bottom end, headers, 92mm throttle body with Holley intake. I'd love to see 350+ at the wheels once tuned before boost.

 

[L92 OLDS]

I want to make 400 at the wheel before turboing It. Any suggestions. And I was told I could use 1.8 rockers to help me with power.

Why set this goal for yourself? Makes no sense when all you need is boost. You can make over a 1000 hp with a boosted, stock junk yard 5.3