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Retired Focus Addict
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Discussion Starter #1
I have quite a few question about port n polishing a head because I just traded my Cossie TB for a head that I am going to port n polish.

First, I am wondering about the porting... some people are telling me that I should make absolutely clear how big I want the ports and to be carful on how big I tell them to make them... What should I tell the people???

I will have the port n polished head, intake, Exhaust soon to be a 2.5", Cossie header, Crane stg. I, and thats all motor wise. I mean I will have the motor mounts and everything but that shouldn't have anything to do with porting.

Second, some people are telling me that this may be useless unless I get bigger valves... I really don't want to make the ports huge... I just want them smoothed out and made just big enough for the mods I will have... so if I have them port and polish them and use all the stock parts including the valves but use the stg. I cams is that going to hurt anything????


I am probably going to drop this thing off tomorrow or Thursday so can ya guys help me out on this?
 

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Like I said in GC, the port and polish job is going to be big. But also I said I don't know much about the Dura motor. You'll be better of finding someone who is experienced with Ford/Focus motors, or 4 cyl motors. Bigger valves will probably be needed due to the more air entering the motor. You'll also need a custom tune to compensate.
 

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The valves are big enough. Promise. The d23 head is already super nice flowing (like the one you currently have on your ST), but I'll bet if you had the ports gasket matched and cleaned up and then had a little bowl work done it would help out.

You might also consider getting it milled in order to increase your compression ratio. You would want to talk to the machine shop about the correct amount to take off to get to the desired ratio, bearing in mind valve clearance, esp. with the cams (and esp. esp. if you adjust them aggressively..lol). You would want to talk to your tuners about changing your tune for the increased compression if it was drastically increased.
 

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Discussion Starter #4
ok here is the deal...

I see that the valves aren't THAT expensive so... the dilemma I have here is I already have the head and traded my Cossie TB off for the head...

I am so so so confused now... can someone PLEASE PLEASE PLEASE give me a detailed description/ answer on what I should do about port n polishing the head???

I have the stock head from a 2.3L and I will get that pretty much built up with the right valves... I really need the correct answer. It would be nice if I DON'T have to get the valve springs though because if I need to I will have to go to Crane stg. 2 because it will be too tempting [:D].

Net said something about enough valve clearance.... what does me porting the head have to do with valve clearance??? I REALLY REALLY REALLY need a good answer here.
 

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Discussion Starter #5
ok well I have been told that when doing a port n polish that bigger valves would be good....

ok,
If I were to get +1MM valves, upgraded valve springs, Crane stg. I cams, what else would I need to do... I hope nothing... I mean do I have to have valve relief done??? Will the pistons hit the valves if I get +1MM valves have the head ported to the +1MM and get stg. I cams and upgraded valve springs????
 

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I'll clarify:

Porting & polishing:

gasket match the ports, clean up the ports. this will make the air flow even through the head up to the size of the gaskets. cleaning up the ports would just be smoothing out whatever is a problem.

get bowl work done if necessary (definately seek a machine shop, you will be getting into valve jobs)

You will prolly just want to gasket match them and clean up the ports.

Milling (decking the head, taking off some of it to decrease the cc of the combustion chamber, thereby increasing compression):

This was just a thought because it would give you more compression ratio, and while the head is off, it would be pretty easy. You would have to go to a machine shop on this one too. The valve clearance issue I was talking about dealt with this. If you get the head decked, the valves will be that much closer to the pistons. This would mean you would have to be careful with the timing of your cams in order to keep the pistons and valves from meeting because they would more easily come in contact with the shorter head/combustion chamber.

Overall:
Oh the assembly of your head, you could theoretically use the same valves, springs, etc. if the wear isn't bad and the machine shop verifies the tolerances. Springs should be fine with stage Is. Valves, I wouldn't just slap them in, they might have to do some grinding.
 

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for once im going to help you out... if you get bigger valves, valve reliefs have to be cut into the head to accomodate them. as far as the port work goes "gasket matching" would increase airflow and be beneficial... not taking a ton of material off but enough that it will give a decent gain all around. pistons would only end up hitting valves if A.) you had the head decked/milled to raise the compression ratio, B.) you played around with cam timing to the point of interference, or C.) you went with such a high lift cam it sent the valve into the piston, or any combination of the 3.. seing as you are in southern california call up randy at focussport and ask them specifically what would be your best bet as far as that goes. i personally deal with ray @ mcnews here on the east coast and hes never steered me wrong. check with the experts before you act... u know the old addage... measure twice cut once. it applies to cars as well. hope this helped.
 

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I would really suggest against milling the head. As an interferance engine, we don't have much room for error, and milling is just asking for trouble. The best thing from a P&P you could do is port-match to the header.

When I went to get head work, Walter talked me into getting a custom 3-angle valve job instead of a P&P. In his experience, the 3-angle showed more improvements over the P&P. However, the downside is Walter is scaling back his operations, and doesn't offer that service any more.

Also, be prepared for some work. Getting that head off isn't an easy task. I replied to your earlier thread with a breif summary of all that needs to be done to remove the head.

And don't forget, you will also be flow limited by the intake manifold. You can make the head flow really well, but if its choked...
 

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Egz said:
And don't forget, you will also be flow limited by the intake manifold.
You can make the head flow really well, but if its choked...
Would a Cosworth intake mainfold take care of this problem?
 

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yes, it would.

You do not need larger valves, the stock size is already rather substantial.

Since Walter doesn't do head work any more another good option is to send it off to extrude hone. The pump and extremely abrasive high pressure goo through the head to clean it up and it works very nicely.

Do not deck the head, listen to egz on that one.

Get an extra shortblock and build that up for the head you're working on. It's much better to swap the whole motor in and out in one go rather than trying to build and rebuild with it inside the car.

Talk to guys that work on honda Kseries motors. The flow characteristics of that head and the duratec head are relatively similar.
 

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Retired Focus Addict
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Discussion Starter #11
ok so when I go to the machine shop I should just telll them that I want the ports smoothed out and matched to the STOCK valves and I want the exhaust ports matched to my Cossie header?
 

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aero_student said:

Get an extra shortblock and build that up for the head you're working on. It's much better to swap the whole motor in and out in one go rather than trying to build and rebuild with it inside the car.

QFT [thumb]

Like I was trying to tell you is that you should build up an entire motor, before using your own. Buy parts here and there. Work on it yourself and on the really difficult parts have someone else do the work that you can trust to do it correctly. It'll be more gratifying in the long run.

Do your homework. Like I've always been told, measure twice-cut once [thumb]
 

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If you are wanting to really build a Duratec then listen to the feedback they are giving you about buying another block you can build up and use your head with.

Otherwise, IMHO, if you're just going to do the typical mods (i.e., I/H/E and SCT tune) then you should just sell the head. The amount of time, effort and $$$ you'll put into making the other head significantly better than stock and getting it installed is better spent elsewhere.

Time to consider the FS turbo again?

EDIT: Figure out what you are getting into BEFORE having anyone work on this head. To get an idea, you might have a few shops quote just the cost of removing one head and installing another. I don't know for sure, but I don't think you're going to like the prices they give you.
 

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There is NO need to do any type of P&P with these heads and keep them NA with a stock bottom end you will be wasting your money

Take these heads to some one that hasent done any before and you could loose power , they flow VERY well for NA , do the boltons and cams with the Cosi intake and let it go

Tom
 

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look at that.. the infamous turbo tom chiming in ... if his knowledge of the focus isnt enough to go by... i dont know what is...
 

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Discussion Starter #16
Yep... too bad I can't find a buyer for this head [:(]
 

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How much do you want for the head? I wouldn't terribly mind having a spare around.
 

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Discussion Starter #20
I dunno how much I should ask... can you maybe make an offer that you think is fair?
 
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