Steam Hole Drilling
Melting Slicks
Joined: Sep 2000
Posts: 3,099
Likes: 0
From: PITTSBURGH PA
Cruise-In IV Veteran
Cruise-In V Veteran
Re: Steam Hole Drilling (bigjack)
bigjack you have two choices
1 drill steam holes now but take it to a competant machine shop to do the work if it works out good if you blow the gasket to the steam hole later just have them welded back up and remachine flat
2 dont drill the steam holes and in my past expierience you will not have any problems
choice 2 is cheaper
choice 1 costs money in the begining if it holds great if they blow and you want to fix them then 3-4 times more money later
the choice is up to you :cheers:
1 drill steam holes now but take it to a competant machine shop to do the work if it works out good if you blow the gasket to the steam hole later just have them welded back up and remachine flat
2 dont drill the steam holes and in my past expierience you will not have any problems
choice 2 is cheaper
choice 1 costs money in the begining if it holds great if they blow and you want to fix them then 3-4 times more money later
the choice is up to you :cheers:
Drifting
Joined: Feb 2003
Posts: 1,978
Likes: 2
From: San Antonio Texas
Re: Steam Hole Drilling (CORKVETTE1)
We had a little discussion about this a while back; everything I've ever read says to drill the holes, but CORKVETTE1 and a few others says I'ts a bad idea. He has actually built, and run these engines, and had problems, but I don't understand why all the articles over many years, say to do it. Cork; did you drill them at the proper angle?
:chevy
:chevy
Melting Slicks
Joined: Sep 2000
Posts: 3,099
Likes: 0
From: PITTSBURGH PA
Cruise-In IV Veteran
Cruise-In V Veteran
Re: Steam Hole Drilling (Curveit)
curveit yes they were drilled at the proper angle the placemant is placemant the angle is only there to assure you hit a water jacket if you go straght down you will not hit nothing you need the angle correct or no water jacket :cheers:
Advanced
Joined: Apr 2003
Posts: 84
Likes: 0
From: Bellevue Nebraska
Re: Steam Hole Drilling (CORKVETTE1)
Seriously?
I'm about to do a mild/street 400 build up and I've always heard that you NEED to drill the steam holes.
It'd save some money on the machine work but I'm a little uneasy with the idea.
Then again, if it helps to prevent blown gaskets . . .
I'm about to do a mild/street 400 build up and I've always heard that you NEED to drill the steam holes.
It'd save some money on the machine work but I'm a little uneasy with the idea.
Then again, if it helps to prevent blown gaskets . . .
Former Vendor
Joined: Jun 2001
Posts: 7,204
Likes: 6
From: St Marys PA
Re: Steam Hole Drilling (Ragtop89)
I am with Corkvette. No need to drill the holes. The overheating scenerio myth on these motors came about from back in the day when 400 were put in cars that had poor cooling systems.
I can tell you first hand my 406 I ran last year ran ~20* cooler on average than my 350 (stock) motor did!!! This was with no steam holes, same radiator, 160 stat, and an Autozone water pump :lol: (it was suppose to be temporary, but I then applied the don't fix it if it aint broke methodology)
I WOULD NOT drill the holes based on my experience and Cork's. I was in the same boat as you, worring early on in the buildup whether to drill them or not. I took Corky's advice and had zero problems. :cheers:
One other thing to mention that no one pointed out with drilling the heads. We all like to keep modding up our cars. Someday, you may decide you want a different combo, or heads. With them drilled out, you are limiting who will buy them off you should you decide to sell them to recoupe some money.
I can tell you first hand my 406 I ran last year ran ~20* cooler on average than my 350 (stock) motor did!!! This was with no steam holes, same radiator, 160 stat, and an Autozone water pump :lol: (it was suppose to be temporary, but I then applied the don't fix it if it aint broke methodology)
I WOULD NOT drill the holes based on my experience and Cork's. I was in the same boat as you, worring early on in the buildup whether to drill them or not. I took Corky's advice and had zero problems. :cheers:
One other thing to mention that no one pointed out with drilling the heads. We all like to keep modding up our cars. Someday, you may decide you want a different combo, or heads. With them drilled out, you are limiting who will buy them off you should you decide to sell them to recoupe some money.
Advanced
Joined: Apr 2003
Posts: 84
Likes: 0
From: Bellevue Nebraska
Re: Steam Hole Drilling (ski_dwn_it)
Ugh!
I know you guys know your stuff but it goes against everything that has been pounded into my head concerning 400 small blocks.
Question - if I don't get the steam holes drilled into my pretty AFR190s then what is the worst that could happen?
Overheating?
Seizing the engine?
Blown gasket?
Question 2- I can still use a 400ci head gasket, correct?
I don't see why not . . .
I know you guys know your stuff but it goes against everything that has been pounded into my head concerning 400 small blocks.
Question - if I don't get the steam holes drilled into my pretty AFR190s then what is the worst that could happen?
Overheating?
Seizing the engine?
Blown gasket?
Question 2- I can still use a 400ci head gasket, correct?
I don't see why not . . .
Former Vendor
Joined: Jun 2001
Posts: 7,204
Likes: 6
From: St Marys PA
Re: Steam Hole Drilling (Ragtop89)
Ragtop.
we would not tell you to do it if we did not KNOW it was OK.
I suggest you use the marine type gaskets felpro offers. They are expensive, but much more durable than standard gaskets since they are intended to perform in the presence of salt water.
Summit has them as does Jegs. Standard 400 gasket should be fine.
I do not know all the detail of all the experiences with all the different setups out there that people have had with cooling issues with. I can tell you that my setup was fine without the steam holes. As I said I suspect that the people that were having issues may have had other factors contributing as well.
:cheers:
we would not tell you to do it if we did not KNOW it was OK.
I suggest you use the marine type gaskets felpro offers. They are expensive, but much more durable than standard gaskets since they are intended to perform in the presence of salt water.
Summit has them as does Jegs. Standard 400 gasket should be fine.
I do not know all the detail of all the experiences with all the different setups out there that people have had with cooling issues with. I can tell you that my setup was fine without the steam holes. As I said I suspect that the people that were having issues may have had other factors contributing as well.
:cheers:
Melting Slicks
Joined: Oct 2003
Posts: 2,951
Likes: 3
From: Mount Vernon OH
Re: Steam Hole Drilling (bigjack)
Another option not mentioned is to O-ring and receiver groove your block and heads. The o-ring is something you will NOT see on your average 400 but if you are worried but want the steam holes this is your answer. People who typically o-ring are mainly blower, turbo and big nitrous users because this is where the cylinder pressure gets crazy and that is when you really push the limits of the gaskets. If you were consider this it will typically cost $250 to $300 but it will save you a ton of time pulling the heads off later.
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Instructor
Joined: Feb 2001
Posts: 211
Likes: 0
From: Chicago ILL
Re: Steam Hole Drilling (ski_dwn_it)
Last summer, I completed the install of my 406. When I purchased heads, I assumed that steam holes were required. Brodix strongly recommended that steam holes NOT be drilled. According to them, the heads have revised cooling passages and do not require steam holes. They do however have a tech bulletin that recommends using FelPro 1004 gaskets and opening four of the cooling passages to 7/16".
Although I do not have that many miles on the motor, I have not experienced any problems thus far.
http://www.geocities.com/dzperf
[Modified by HiTech5, 2:51 PM 4/7/2004]
Although I do not have that many miles on the motor, I have not experienced any problems thus far.
http://www.geocities.com/dzperf
[Modified by HiTech5, 2:51 PM 4/7/2004]
Advanced
Joined: Apr 2003
Posts: 84
Likes: 0
From: Bellevue Nebraska
Re: Steam Hole Drilling (HiTech5)
Hey, Jesse, I'm not trying to be a turd or anything.
I know you and Cork are making GOBS of power and I enjoy following your exploits in the pursuit of Naturally Aspirated speed.
I learned my lesson a long time ago to take all advice with a grain of salt.
I don't want to take this engine to any extremes.
I just want to be able to pull her out of the garage once a week and put my foot in her.
I appreciate your advice and your willingness to share your knowledge! :D
I know you and Cork are making GOBS of power and I enjoy following your exploits in the pursuit of Naturally Aspirated speed.
I learned my lesson a long time ago to take all advice with a grain of salt.
I don't want to take this engine to any extremes.
I just want to be able to pull her out of the garage once a week and put my foot in her.
I appreciate your advice and your willingness to share your knowledge! :D
Former Vendor
Joined: Jun 2001
Posts: 7,204
Likes: 6
From: St Marys PA
Re: Steam Hole Drilling (Ragtop89)
ragtop.
No need to appologize. I just want to you make the right choice.
Remember also, most of these 400s back in the day were sporting iron heads. All of which contributed to heat problems.
I agree with the last poster, that BRODIX doesn't suggest the steam holes. Aluminum disapates the heat much easier.
Just covering your back for you :thumbs: :cheers:
No need to appologize. I just want to you make the right choice.
Remember also, most of these 400s back in the day were sporting iron heads. All of which contributed to heat problems.
I agree with the last poster, that BRODIX doesn't suggest the steam holes. Aluminum disapates the heat much easier.
Just covering your back for you :thumbs: :cheers:
Le Mans Master
Joined: Feb 2000
Posts: 9,715
Likes: 27
From: Kempner Texas
Re: Steam Hole Drilling (ski_dwn_it)
We called Hendrick Motorsports last year about this very topic.
Here's what we learned: If the engine RPM will remain above 3000, no steam holes are required. If the engine is operated below that speed, then the steam holes should be drilled.
This came up during my build-up of a 434 SB using Brodix 15 degrees heads and a new BowTie block.
The FelPro head gaskets we used came with instructions on enlarging certain "other coolant passages" in the block, which early 400 blocks need to have done, but the BowTie didn't.
On my personal 415, I drilled the "other coolant passages" as recommended by FelPro and I also drilled my Edelbrock heads for steam holes using the head gasket as a template.
Jake
Here's what we learned: If the engine RPM will remain above 3000, no steam holes are required. If the engine is operated below that speed, then the steam holes should be drilled.
This came up during my build-up of a 434 SB using Brodix 15 degrees heads and a new BowTie block.
The FelPro head gaskets we used came with instructions on enlarging certain "other coolant passages" in the block, which early 400 blocks need to have done, but the BowTie didn't.
On my personal 415, I drilled the "other coolant passages" as recommended by FelPro and I also drilled my Edelbrock heads for steam holes using the head gasket as a template.
Jake
