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Discussion Starter #1
Humphrey can ask his own question in a new one, there's lots of info on the 2.3 heads in there & using them on a 2.0 as well but I'm not sure of his questions.

"skim cut" for a flat surface doesn't affect C/R much, CAN be cut a bit more if desired.

What he meant by 'changing internals" of the head I'm lost on. Valves/cams/porting?

Don't want to add this to a thread that doesn't apply.

A little research in BOTH Duratec sections might be good, again it depends on his goals with the head.

So I am going to hunt down a D23 head and start on it while I look for the rest of my engine.
Ive chosen to go with what seems to be the favourite of FF which I believe is a D25 block w/D23 head.

Skim cut or decking the head has been suggested as they warp which ive been told changes the c/r (which idk what that is yet) and could even have it cut more if so desired. What are the pros/cons? Explain or link to thread would be fine.

As for internals. I am talking cams and valves but don't know what porting is yet. Read something about buckets and adjustable cam gears or something idk.


Will be reading. Links are helpful.
 

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c/r is how many air units there are for every 1 fuel unit. an engine is an air pump. the more air you can get to explode the more power you make. unless im terribly mis-guided
a resurface will change the c/r but its negligible. couldn't tell you what are the pro's cons of doing more than just a shave.

you match valves/valve springs to the cams you choose. cams will have lift, duration, and overlap. those are the most impactful ones iirc. you'll also want adj cam gears or the ability to read cam degrees on your own for dyno adjustments. for the sake of keeping it easy, get gears.
this link may help. it was a quick google, im sure there is better info out there. http://www.lunatipower.com/Tech/Cams/CamSpecTerms.aspx
 

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Discussion Starter #3

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yea matching like that it appears that youll need machine work on your pistons for those... if im reading that right
"valve relief in your pistons, regardless of how high you plan on revving your engine."
http://static.summitracing.com/global/images/prod/large/srp-206066_w.jpg

think i found the same thing for less
http://www.c-f-m.com/performancepar...0&pageStyle=h&idcategory=69&VS3=0&VS2=0&VS4=0

250 for cam gears
300 for cams
440 for cam springs if cosworth is what you want
+cost of resurface head
+cost of creating more relief in pistons

while youre at it might as well do a mild bore and port/polish

port/polish=machining intake and exhaust ports to be wider/smoother
 

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Discussion Starter #5
Crower VS Crane VS Cosworth - FIGHT!
 

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lol youre on your own for that. look into the overlap, lift and duration and use the specs to figure out which one you want XD
 

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Going to have to ask a know it all cause I am lost when it comes to that.
 

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call for iminhell. he seems to be one of them. or ftc... they should correct me if im mistaken and add info
 

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Before you pick cams you need to decide on

Compression
header what one
exh what size
intake
what intake manifold
are you porting the head
what will this Focus be used for
all these things need to be decided to choose the proper cams

Compression ration is how much air is compressed into top of the piston and combustion chamber on the compression stroke

Tom
 

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Discussion Starter #10
I've no experience in this AT ALL so what I am going to do is take suggestions and go with that. This will most likely be a daily driver, not going to the track or racing anyone- I just like to drive and to drive spirited.
 

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Crower VS Crane VS Cosworth - FIGHT!
I like the narrow lsa of the cranes over the crowers even thou the crowers have more duration at .050. The cossie's & copy cat obx's are single pattern cams, while the crane/crowers are dual pattern. btw 420svt has a 23 head for sale.
 

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c/r is how many air units there are for every 1 fuel unit.
Close, but you're thinking of an air/fuel ratio (A/F ratio).

The compression ratio (c/r) is the amount of compression applied to a cylinder. A 10:1 c/r means that 10 units of air/fuel mixture will be compressed 10-fold to the size of 1 unit.
 

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Close, but you're thinking of an air/fuel ratio (A/F ratio).

The compression ratio (c/r) is the amount of compression applied to a cylinder. A 10:1 c/r means that 10 units of air/fuel mixture will be compressed 10-fold to the size of 1 unit.
yea i messed up, thx tho!
 

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I've no experience in this AT ALL so what I am going to do is take suggestions and go with that. This will most likely be a daily driver, not going to the track or racing anyone- I just like to drive and to drive spirited.
Best bang for the work/buck would be a 23 w/ a set of mild cams, header & a bsd. A 23 will get you DD grunt that you won't see w/ a 20.
 
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