Diputado

Hey folks,

I've been researching aluminum heads for my 289 over the past several weeks, and have noticed that some (TFS, Edelbrock) recommend drilling "steam holes" in the block deck surface to match those that come on the heads, in order to avoid overheating problems, they claim. Others (AFR,etc.) apparently don't have these holes or recommend them. What's the deal here? Are there significant advantages to these steam holes? If so, why didn't Ford catch on way back and make them standard? Or, are they just unnecessary additional complications? Opinions...experiences?

67mustang302

Steam holes for what....steam? If you have steam in your cooling system, not having steam holes is the least of your worries.

barnett468

just buy the heads and bolt them on.

please post the link to where you say this. if edelbrock wanted additional holes in their heads they would have put them in there themselves.

Gun Jam

Trick flow "requires" them as well they want them drilled on the deck in that triangle section between the cylinders.

I went about trying to figure out if they were worth the effort when I realized it was more effort searching than it was to just drill them. I figured Trick flow wants them, the head gasket has provisions for them and I can't get a straight answer on how important they really are...**** it drill em.

barnett468

something doesn't make sense. i havec never drilled eddy heads or seen instructions from eddy to do so.

as long as the aluminum heads have the same number of holes as the orig heads there should be no reasin to drill additional holes unless the head design sucks. they are aluminum heads, they run cooloer than iron heads so why should they run hot and why dores not trick flklow drill them out before delivery?

Gun Jam

You dont drill the heads you drill the top of the block. The heads do have provisions for the steam holes. The steam holes you drill go into the water jacket from deck surface on the block and allow water to pass up into those passages in the head.

-Gun

barnett468

ok got ya thanks. i have never done that and never had a prob with eddy heads anyway.

barnett468

ok found it. if trick flow does say to do it so do it i guess. since real heads like eddy's and afr's say not to then don't do it when using their heads. the eddy and afr heads apparently do not cause this problem that the trick flows do.

Trick Flow Twisted Wedge heads need pre 72 block water holes added.

"Note that the large coolant holes always go toward the rear of the block. If you have a pre-1972 block or a 351 SVO block, you must modify the coolant passages in the deck surface as shown in . Using the head gasket as a template, drill into the water jacket at the locations shown with a 3/16 in. drill bit. This modification must be done to prevent overheating due to steam pockets forming in the high side of the block. Be sure to tape off or otherwise cover the deck surface and cylinder bores when you are drilling."

http://static.trickflow.com/global/i...400002(2)1.pdf

Starfury

I drilled my block when I installed my Twisted Wedge heads. No adverse affects...

Mikebell

l asked tech (Howard)at trick flow about drilling steam holes in pre 1972 ford 302.His response was that it was not necessary, contrary to instructions. Confusing