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Milling my head , any advice?
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Author:  Michael Harley Glass [ Fri Jul 12, 2002 7:37 am ]
Post subject:  Milling my head , any advice?
Thinkin bout milling my head on my mostly
stock /6, I have one from a '73 dart that
will be swapped on to my '66 Belvedere.
I want to go .100 to get the compression
in the 9's. Any advice? comments?

Demonboy71@yahoo.com
Author:  Dart270 [ Fri Jul 12, 2002 7:56 am ]
Post subject:  Re: Milling my head , any advice?
Quote:
: Thinkin bout milling my head on my mostly
: stock /6, I have one from a '73 dart that
: will be swapped on to my '66 Belvedere.
: I want to go .100 to get the compression
: in the 9's. Any advice? comments?


When you find a place to do it, make sure to get a quote beforehand, AND measure the head before and after to see if they actually milled it the proper amount. It is very common for shops to claim they milled it what you asked, and to only have done it 0.010 or something.

Lou
Author:  Michael Harley Glass [ Fri Jul 12, 2002 8:08 am ]
Post subject:  Re: Milling my head , any advice?
Quote:
: When you find a place to do it, make sure to
: get a quote beforehand, AND measure the head
: before and after to see if they actually
: milled it the proper amount. It is very
: common for shops to claim they milled it
: what you asked, and to only have done it
: 0.010 or something.
:
: Lou

Thanks, Lou. I'll have to keep that in mind.

Demonboy71@yahoo.com
Author:  Doctor Dodge (Doug Dutra) [ Fri Jul 12, 2002 9:50 am ]
Post subject:  Re: Milling my head , any advice?
Quote:
: Thinkin bout milling my head on my mostly
: stock /6, I have one from a '73 dart that
: will be swapped on to my '66 Belvedere.
: I want to go .100 to get the compression
: in the 9's. Any advice? comments?


.100 off the head with a stock cam and a good ring seal engine (no leak-down issues) will most likely push you to run premium fuel.
If you go with more cam, it will off-set the higher compression some.
Do some minor "pocket porting" while you are working on the new head.
DD
Author:  dusteridiot [ Fri Jul 12, 2002 6:59 pm ]
Post subject:  Re: Milling my head , any advice? *PIC*
Quote:
: When you find a place to do it, make sure to
: get a quote beforehand, AND measure the head
: before and after to see if they actually
: milled it the proper amount. It is very
: common for shops to claim they milled it
: what you asked, and to only have done it
: 0.010 or something.


Another thing to worry about is your pushrod length, I decided on the 0.100 spec, but took .090 of the block deck and .010 off the head.
With a Felpro composite head gasket that got me into the 9.22:1 CR range, but at the price of calling up Smith Brothers and ordering a custom set of pushrods to put the valve train geometry back into spec...(The cup on a stock pushrod would've contacted the inner edge of the rocker arm during a valve opening event...not good.)

-D.Idiot



Image
Author:  Michael Harley Glass [ Sat Jul 13, 2002 6:04 am ]
Post subject:  Re: Milling my head , any advice? :Attn:D. Idiot:
Quote:
: Another thing to worry about is your pushrod
: length, I decided on the 0.100 spec, but
: took .090 of the block deck and .010 off the
: head.
: With a Felpro composite head gasket that got me
: into the 9.22:1 CR range, but at the price
: of calling up Smith Brothers and ordering a
: custom set of pushrods to put the valve
: train geometry back into spec...(The cup on
: a stock pushrod would've contacted the inner
: edge of the rocker arm during a valve
: opening event...not good.)
:
: -D.Idiot


Hi
D.Idiot. I have a ? for you. Since you have a
198 /6 that means you can take .090 out of youre
block deck hieght? Im running a 225 w/my setup.
P-s: Dusters rule- I got 3 of 'em!


Demonboy71@yahoo.com
Author:  Michael Harley Glass [ Sat Jul 13, 2002 6:13 am ]
Post subject:  Re: Milling my head , more ?'s
Quote:
: Hi
: D.Idiot. I have a ? for you. Since you have a
: 198 /6 that means you can take .090 out of
: youre
: block deck hieght? Im running a 225 w/my setup.
: P-s: Dusters rule- I got 3 of 'em!


Would I have to worry about pushrod length with .100 removed from the head? And about how expensive was it to take .090 off the 198 block?
The machine shop wanted $75 to take .100 off of the head. Good deal or bad deal? Thanks -D.Idiot
and everyone else who replied!
Mike


Demonboy71@yahoo.com
Author:  dusteridiot [ Sat Jul 13, 2002 4:57 pm ]
Post subject:  Re: Milling my head , any advice? :Attn:D. Idiot:
Quote:
: D.Idiot. I have a ? for you. Since you have a
: 198 /6 that means you can take .090 out of
: youre block deck hieght? Im running a 225 w/my setup.


My car is a 1976 Feather Duster, the pic you saw was my numbers matching (like it matters)225 block that's been bored 20 over (If I had a 198, my build would have changed...).
In any stock 225 the pistons sit like an inch below the deck, I think someone here said they've taken as much as .140 off the deck and been ok for stability.

My machinist has done a couple of slants (I live in Oregon), and had some ideas and recommendations. He suggested doing the deck and the head that way so in an emergency I could used the head on another slant without worrying about compression problems, and also it would still have plenty of meat to replane it a few more times. The head is a harder to find 1975-1978 "600" non-smog port head, so I wanted to keep it for as long as possible.

That's my two cents worth...

Just as an FYI, Doc had a pic of a really cool way to check for proper push rod lenght after assembling the engine:
Cut a stock push rod in half, then thread both halves and rejoin with two nuts an a peice of all-thread stock (of part of a cut off bolt). You can then adjust the length to whatever looks best with your feeler guages, then send the rod into smith brothers for the correct pushrods...
:
: P-s: Dusters rule- I got 3 of 'em!

I used to own 3 Dusters, now I own 2 and a half...

-D.Idiot
Author:  dusteridiot [ Sat Jul 13, 2002 5:05 pm ]
Post subject:  Re: Milling my head , more ?'s *PIC*
Quote:
: Would I have to worry about pushrod length with
: .100 removed from the head?


Most people do, my 225 did. I just posted a description of how to measure it, but someone else (DOC?!!??)might have a pic of the tool...
:
: The machine shop wanted $75 to take .100 off of
: the head. Good deal or bad deal? Thanks

I paid something like $300 for my head..of course I got all of the following too...

Bronze guides, Hardened seats, new valves finished to proper length, i was allowed to pick up my head with the unfinished guides in it so I could port my head, then drop it back off to finish the guides, had my springs checked, hot tank the head, plane .010 off, guides were cut for positive seals, but I put standard balloon seals on it and they fit beautifully.

Hope that helps somewhat...

-D.Idiot



Image
Author:  elam [ Sat Jul 13, 2002 6:09 pm ]
Post subject:  Re: Milling my head , more ?'s
Quote:
: Would I have to worry about pushrod length with
: .100 removed from the head? And about how
: expensive was it to take .090 off the 198
: block?
: The machine shop wanted $75 to take .100 off of
: the head. Good deal or bad deal? Thanks
: -D.Idiot
: and everyone else who replied!
: Mike

I took .100 off my 75 dart 225 head and am useing my stock push rods. They just fit but I dont like the looks of them. I havnt had any problem yet but I need to change them sometime. Over on .com an .080 shorter push rod part number was listed it was sealed power # RP3036 check this out first as I havnt looked into it yet but i've only got good advice from this sourse so far.


melam@nxs.net
Author:  elam [ Sat Jul 13, 2002 6:15 pm ]
Post subject:  Re: Milling my head , more ?'s
Quote:
: I took .100 off my 75 dart 225 head and am
: useing my stock push rods. They just fit but
: I dont like the looks of them. I havnt had
: any problem yet but I need to change them
: sometime. Over on .com an .080 shorter push
: rod part number was listed it was sealed
: power # RP3036 check this out first as I
: havnt looked into it yet but i've only got
: good advice from this sourse so far.

I just looked on Advance Auto parts site and they have them for 3.29 apeice if they are shorter that aint bad.


melam@nxs.net
Author:  Michael Harley Glass [ Sun Jul 14, 2002 4:08 pm ]
Post subject:  Re: Milling my head , any advice?
Quote:
: .100 off the head with a stock cam and a good
: ring seal engine (no leak-down issues) will
: most likely push you to run premium fuel.
: If you go with more cam, it will off-set the
: higher compression some.
: Do some minor "pocket porting" while
: you are working on the new head.
: DD


Thanks everyone,

And I also have a b5 feather duster,d.i

Now I'll have to get to it. For the

next ?'s I have wll be porting of the

head, what tools did you use ?(grinder,etc)

I'd like to port the head myself if at all possible.



Demonboy71@yahoo.com
Author:  dusteridiot [ Sun Jul 14, 2002 6:50 pm ]
Post subject:  Re: Milling my head , any advice?
Quote:
: Thanks everyone,
:
: And I also have a b5 feather duster,d.i


Cool would like to see some pictures...

I have wll be porting of the
:
: head, what tools did you use ?(grinder,etc)
:
: I'd like to port the head myself if at all
: possible.

Pretty easy, just need some "marking" compound, a scratch awl, your intake/exhaust gasket, a die grinder (like a 1/4" air grinder), and the best die is a titanium carbide rasp from Snap-On (borrowed that die from a friend who ports up a lot of chevy heads. that rasp and 1 hours worth of carefuly work should do the trick. When in doubt, find a junk head to work on and feel the difference in what you're working on vs. the head you're really going port.

-D.Idiot

-D.Idiot
Author:  Michael Harley Glass [ Mon Jul 15, 2002 8:01 am ]
Post subject:  Re: Milling my head , any advice?
Quote:
: Cool would like to see some pictures...
:
: I have wll be porting of the
:
: Pretty easy, just need some "marking"
: compound, a scratch awl, your intake/exhaust
: gasket, a die grinder (like a 1/4" air
: grinder), and the best die is a titanium
: carbide rasp from Snap-On (borrowed that die
: from a friend who ports up a lot of chevy
: heads. that rasp and 1 hours worth of
: carefuly work should do the trick. When in
: doubt, find a junk head to work on and feel
: the difference in what you're working on vs.
: the head you're really going port.
:
: -D.Idiot
:
: -D.Idiot

Okay, some more ?'s . What is the use of the scratch awl for? And other than that all I have to
do is get a carbide tip and begin? Are they done
in grits like sandpaper or all the same?? What about polishing. Thanks- D.I


Demonboy71@yahoo.com
Author:  dusteridiot [ Mon Jul 15, 2002 8:38 pm ]
Post subject:  Re: Milling my head , any advice?
What is the use of the
Quote:
: scratch awl for? And other than that all I
: have to
: do is get a carbide tip and begin?


O.k. there's a good article on how to port the head on the internet, but I can't find the book mark...

pretty easy, you dope up the ports with the marking compound to make them off color (usually purple), let the stuff dry, then use your gasket as a template and use the scratch awl to mark around the inside of the gasket cut outs of the ports...this gives you a baseline of how much could be hogged out of the mouths, you have to go easy on the throats, and around the valve seats.

If you are doing a drag port job, then by all means get a set of different grit wheels to finish polish the ports.

In a street port (since mine is soon to be a daily driver), the polished ports don't help much since most driving is at lower RPM, to a rougher/unfinished port job would be good enough (some differences of opinions will occur here).
This job can just be done with the rasp and is quicker that way. It just chews off the rough edges and can hog out the material pretty fast.
In this porting you just want to take away any excess material, smooth out any rough spots and casting flash (dingleberries?), and "round" out and sharp curves and corners (smoooooth...not glass though)

I was lucky to have a friend who has done loads of heads for his own rides, and other projects, to guide me on what to expect, and even ran his fingers over spots and told me what to do...

hope these ramblings are helping out...
Just watch out around the roof of the runners it can get thin in some cases (then you'll need another head), but if you just smooth it out and don't hog out a trench you should be o.k.

-D.Idiot
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