Guest Russ240z Posted March 10, 2002 Share Posted March 10, 2002 I just pulled the heads off my 400sbc and found they were not drilled for steam holes. Not suprised because the temp would soar to 225 degrees after making a single pass at the strip. What has to be done when drilling holes to do it properly? Hole size, depth, number, etc...? Do aluminum heads present any different requirements? Is this something I can do myself or is professional needed? Thanks. Quote Link to comment Share on other sites More sharing options...
biohzrd Posted March 10, 2002 Share Posted March 10, 2002 well it is usually better to have a shop do it. if you want to do it yourself you can. buy a set of head gaskets for a 400 and mark the steam holes. as far as how deep to go thats easy. just drill until you hit the water passages. usually it's about a 1/4 inch thick. Quote Link to comment Share on other sites More sharing options...
grumpyvette Posted March 10, 2002 Share Posted March 10, 2002 stop!!!!!!!! you do not drill all the holes strait down!!!! 400 BLOCKS: Steam holes are recommended for all 400 block applications. Use a 400 gasket as a template and drill the three holes nearest the spark plug side of the head straight down, the other three which are very near the head bolt holes should be drilled at a 30 degree angle away from the bolt hole. The center hole will intersect water about 1" down and the two outboard holes to a depth of 2 1/4". Use a 1/8 drill. Quote Link to comment Share on other sites More sharing options...
Guest Russ240z Posted March 10, 2002 Share Posted March 10, 2002 The head gasket (felpro 1004) did not have the holes either. I verified the part number is for a 400sbc. What's up with this? If they are that important, why are the holes not cut in the gasket? Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted March 11, 2002 Share Posted March 11, 2002 felpro 1004 can be used for the 400 but felpro states its not for street operation or for engine speeds below 3000 rpm for the 400... i use felpro 1014. grump is right on the drill and the angle on a factory head and most aftermarket heads as well. but if you are using edelbrock victor jr. heads you can drill the 1/8" steam holes straight into the head, anyone else have anything to add? Quote Link to comment Share on other sites More sharing options...
Guest chevsun Posted March 11, 2002 Share Posted March 11, 2002 Drill Edelbrock RPM heads at an angle on the intake side edelbrock says 30 degrees. I recommend having a shop do it as a drill press or bridgeport will not allow the drill bit to wander. Be very careful if you do it yourself you can cost yourself a lot of money with a slip. Start with a very small drill bit for a pilot hole then bring to size. If your going to use a hand held drill do not prick punch aluminum or brass as this makes the pricked area slightly harder than the surrounding aluminum and "may" cause a hand held drill to wander.I was just informed this last week in Machinist class. Good luck Steve Quote Link to comment Share on other sites More sharing options...
Guest Russ240z Posted March 12, 2002 Share Posted March 12, 2002 Thanks for the info guys. BTW I'm planning to order new aluminum heads from Canfield or AFR. When ordering heads can I specify that the steam holes be drilled by the manufacturer? Quote Link to comment Share on other sites More sharing options...
Guest chevsun Posted March 12, 2002 Share Posted March 12, 2002 Russ240Z: If you are buying AFR's they will build the heads as you want them for the cam and with the steam holes I believe that the holes cost an extra $50 and a spring upgrade is $125. I dont know about canfield. If you are considering AFR's The guy at www.flatlanderracing.com told me there is a 3-4 week backorder on AFR's he is helpful and patient even with me. Check his prices. Steve Quote Link to comment Share on other sites More sharing options...
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