Question about 400's
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
The block has them. The question is whether or not to drill the heads. All the known authorities say, "yes", for use under 3500 rpms. Quite a few on here report no overheating problems without them. It can't hurt.
RACE ON!!!
RACE ON!!!
Former Vendor
Joined: Jun 2001
Posts: 7,204
Likes: 6
From: St Marys PA
Originally Posted by lucky85
Do I want steam holes or no steam holes on a street 400?
If you do drill the heads, plan on blowing head gaskets on regular intervals.
The "overheating" myth has come about back in the day when the cooling systems were at best marginal -steel, thin radiators. In fact, my 406 ran cooler than my stock 350 did with the same pump and cooling system.
Also consider resale of your heads after you drill them out. They will be worth nothing.
I would also recommend the use of "marine" Fel-pro head gaskets, these are tougher and will tolerate the increased exposure to the water and steam.
Lastly, if you can afford the aftermarket blocks, they are worth their weight in gold, I can get you some REAL good deals on them if you should choose to go that route. To the tune of ~300 dollars less than Summits prices for Dart blocks.
They are without a doubt - the bullet-proof route.
Le Mans Master
Joined: Feb 2000
Posts: 9,715
Likes: 27
From: Kempner Texas
Originally Posted by lucky85
Do I want steam holes or no steam holes on a street 400?
I even called Hendrick MotorSports (one of the premier NASCAR engine builders) and asked them about it. I was told the same thing; drill 'em.
I drilled my heads.
But, as always, you can do what you want.
Jake
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Former Vendor
Joined: Jun 2001
Posts: 7,204
Likes: 6
From: St Marys PA
Originally Posted by lucky85
I did but some say do it and some say that it is not needed
Code:
Name CI Drilled (yes/no) Trouble(yes/no) Ski 406 No no Corky 406 NO no Ralph 406 No no Sure there are many more with the same answers
Last edited by ski_dwn_it; Jan 27, 2005 at 08:58 PM.
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Originally Posted by lucky85
so drill them or dont drill them.
It will be a daily driver
It will be a daily driver
Originally Posted by CFI-EFI
Reread ALL the posts over.
Originally Posted by lucky85
I did but some say do it and some say that it is not needed
RACE ON!!!
Pro
Joined: Jan 2002
Posts: 718
Likes: 0
From: W.V.C. Utah
Originally Posted by ski_dwn_it
Code:
Name CI Drilled (yes/no) Trouble(yes/no) Ski 406 No no Corky 406 NO no Ralph 406 No no Sure there are many more with the same answers
Melting Slicks
Joined: Oct 2003
Posts: 2,951
Likes: 3
From: Mount Vernon OH
I have drilled them with no problems and I spray with 250 to 300 horsepower of nitrous with no issues and I am NOT running copper head gaskets either. Your major issue is that you MUST have flat surfaces (heads and block). Call Cometic Gaskets at (440) 354-0777. This company makes head gaskets for engines up to and over 2000 horsepower with tremendous cylinder pressures that would typically require o-rings and receiver grooves such as blowers, turbos and nitrous applications. I am not running these gaskets but if you are worried I would drill the heads and buy Cometic gaskets. Ask for the following gasket #C5327-027 and order 2 of them because they come individually. The 27 at the end of the part number is for 27 thousand thickness and if you need something thicker they will adjust your part number to what you need. There gaskets are multi-layer stainless steel. Warren & Kurt Johnson, Greg Anderson run them, tons of big nitrous users and turbo guys are running these gaskets with cylinder pressures in excess of 2200. This gasket also has steam holes and that alone should answer your question of "do you drill or not".
Last edited by NitrousSam; Jan 28, 2005 at 01:30 PM.
Le Mans Master
Joined: Feb 2000
Posts: 9,715
Likes: 27
From: Kempner Texas
Originally Posted by lucky85
Well I surelly trust your knowledge so I will just plug,deck and install.Thank you
Either Hendrick Motorsports, Childress Racing or Reher & Morrison in Arlington, TX. These guys have mulit-million dollar operations and have forgotten more about how to put together the SB engine than all of put together will ever know.
I was amazed at how helpful they were when I called Hendrick. I learned that many of the things we tend to think are sacrosanct are just so much non-sense - like all header tubes should be the same length, etc.
When I visited Reher & Morrison I sat down in their cafeteria with a group of the engine guys during their lunch break. The stuff they laid on me had my head swimming. I couldn't take notes fast enough.
They may not tell you what cam lobe profiles they run or what air bleeds they use in their carbs, but I'm sure they'll help you with the mundane stuff.
Do yourself a favor and do your homework. School ain't out til you die.
Jake
Team Owner
Joined: Jul 2002
Posts: 22,267
Likes: 15
From: The light that never warms.
St. Jude Donor '12
Think about this. Chevrolet has a lot of very good engineers, who designed the steam holes in the 400 for a reason. The siamesed bores need to cool off some how.
Burning Brakes
Joined: Nov 2003
Posts: 914
Likes: 1
From: Redding Ca
I am considering a 400 block for my '88. When I do, no matter the final configuration, detonation will be a major issue to address. It just seems like common sense to me that the more water circulating through the cylinder heads will transfer more heat away from the combustion chamber, particularly near the exhaust valve.
From reading these posts, it sounds like no one has any verifyable data, just anecdotal info (isn't that always the case?).
I think the advice to check with the pros is well taken. For me, Lingenfelter has already answered the question. 
From reading these posts, it sounds like no one has any verifyable data, just anecdotal info (isn't that always the case?).
I think the advice to check with the pros is well taken. For me, Lingenfelter has already answered the question.