400 small block ?

greg fulk · 04-23-2007, 12:05 AM

hey guys have a 400 small block chevy ?..... a buddy @ work bought one complete to build into a street strip engine. question if he puts Dart sportsman II heads on it will he have to drill steam hole in them?? somebody told him he had to & I just don't know? Thanks Greg

novamoation

SSDiv6 · 04-23-2007, 09:49 AM

Yes, he does have to dril the steam holes. I would rather build a 383 based on a 350 block. The 400 blocks are known to crack in the valley area when you strat to make power wtih the OEM block. Seen this happen several times.

Dave Goob Cook · 04-23-2007, 10:01 AM

They are not necessary, and many aftermarket heads don't even have water jackets where you would need to drill into them.

Now if you were building the engine for a tow truck or van, or an endurance racing application you'd rather have the steam holes, but with a proper cooling system, it would never be an issue.

"Despite the high cost of living, it remains popular"
Dave Cook
C375

04-23-2007, 12:05 AM	#1
greg fulk VIP Member Join Date: Jan 2003 Location: jackson Posts: 1,165 Likes: 0 Liked 5 Times in 3 Posts	400 small block ? hey guys have a 400 small block chevy ?..... a buddy @ work bought one complete to build into a street strip engine. question if he puts Dart sportsman II heads on it will he have to drill steam hole in them?? somebody told him he had to & I just don't know? Thanks Greg novamoation __________________ Greg Fulk 308 308X P/SA "ALL AMERICAN"

04-23-2007, 10:01 AM	#3
Dave Goob Cook Member Join Date: Dec 2006 Location: Indy Posts: 422 Likes: 0 Liked 0 Times in 0 Posts	They are not necessary, and many aftermarket heads don't even have water jackets where you would need to drill into them. Now if you were building the engine for a tow truck or van, or an endurance racing application you'd rather have the steam holes, but with a proper cooling system, it would never be an issue. "Despite the high cost of living, it remains popular" Dave Cook C375 __________________ "Despite the high cost of living, it remains popular." Dave Cook NHRA N375

04-23-2007, 09:49 AM	#2
SSDiv6 VIP Member Join Date: Feb 2003 Location: Glendale, Arizona Posts: 2,999 Likes: 693 Liked 1,470 Times in 550 Posts	Yes, he does have to dril the steam holes. I would rather build a 383 based on a 350 block. The 400 blocks are known to crack in the valley area when you strat to make power wtih the OEM block. Seen this happen several times.