tony480

In the process of putting together a new 418 for my airboat. Build consists of new LS3 block,k1 4.00" crank,k1 h beam rods,wiesco -3cc coated pistons. New cnc Gm LS3 heads, comp cams .598/.602 236/244@.50 cam with 114 lsa. Holley hp efi with 42# injectors. Should have it together and on the dyno in the next few weeks. Curious to see what she makes. Should be pretty decent. Any guesses as to what she'll make?

andrelossem

Anywhere from 520 to 560 at the flywheel plus or minus for either number there are a lot of different veritable's header size,compression and other things.

tony480

11.5 to 1 compression with long tube 1 7/8 headers with 3" collectors

andrelossem

You could get maybe 600 with more lift. Think about it this way remember the 408 head test in hot rod that could be used as a similar reference. It won't be that much of a difference.

sbf

i would say at least 600 flywheel hp.stock ci ls3 with cnc heads cam intake make 550+

andrelossem

Check this out your exact build Lil John posted this for the 418 cam help on the Gen 4 section it's from Super Chevy: (626HP LS3 Stroker Build - Supersize Me) it is a 418 ported ls3 headed combo that's real simple.

1989GTA

I agree. You should have no problem exceeding 600 horsepower.

tony480

Good...that's my goal...anything over 600 is a bonus....and then add a 150 **** of juice to it...should push the boat ok.