It is safe to resurface my cylinder head?

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In XS 7
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It is safe to resurface my cylinder head?

Post by In XS 7 »

Hi guys, I just bought a ported and polish head and I told my friend that I will get it resurfaced it and he told me that try to put it just like that (with out resurface it) first and if it don't seal good then get it resurfaced, because some times a head had been resurfaced to many times and it will be ruined if I do it again, so now I wonder how much of a material can be take away from a head before it is to much? or how can I know if my head still have enough metal to be shave again? should I just try it on first and see if it don't leaks? or should I get it resurfaced no matter what?
Also the guy at the machine shop told me that all the heads get warped as soon as you get them off the block and so every one needs to be resurfaced, it is that true? or he just want me to pay for the job even if I really don't need it? Thanks again. :cheers
Miguel.
89 XR4Ti Monique; Waking up a real "Night/Mare-Coor".
T5, NPR IC, PIMP ECU, Walbro 255, Dual piston BOV, Manual BC, 3" exhaust, One piece Aluminum drive-shaft, mc2 LSD, Boport 1.5 cam, Ported and polish head, big valves, 80# injectors, Bob's log, (soon HY35).
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Re: It is safe to resurface my cylinder head?

Post by GPz11 »

Well, how about you just check it yourself??

The instructions are in the service manual.

Pretty easy, get a good straight edge and some feeler gauges and measure it.
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Re: It is safe to resurface my cylinder head?

Post by In XS 7 »

GPz11 wrote:Well, how about you just check it yourself??

The instructions are in the service manual.

Pretty easy, get a good straight edge and some feeler gauges and measure it.
I prefer to pay for getting resurfaced instead of buying tools that I don't use very often and then I will have to pay for the machining anyway.
Like the title said "It is safe to resurface my cylinder head?" If it is ok, I just will do it, but, if there is some risk I prefer to take the chance and put it like it is and see if it don't leaks.
But by your answer, I think the head is not always warped, that is why you want me to check it with a straight edge, right?
But the question remains: " It is safe to resurface my cylinder head". :cheers
Miguel.
89 XR4Ti Monique; Waking up a real "Night/Mare-Coor".
T5, NPR IC, PIMP ECU, Walbro 255, Dual piston BOV, Manual BC, 3" exhaust, One piece Aluminum drive-shaft, mc2 LSD, Boport 1.5 cam, Ported and polish head, big valves, 80# injectors, Bob's log, (soon HY35).
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Re: It is safe to resurface my cylinder head?

Post by In XS 7 »

Oh, I see, I will try to do my best to find out if it need it. I will use the best thing I can find as traight as I got to check the surface of the head. Thanks. :cheers
Miguel.
89 XR4Ti Monique; Waking up a real "Night/Mare-Coor".
T5, NPR IC, PIMP ECU, Walbro 255, Dual piston BOV, Manual BC, 3" exhaust, One piece Aluminum drive-shaft, mc2 LSD, Boport 1.5 cam, Ported and polish head, big valves, 80# injectors, Bob's log, (soon HY35).
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Re: It is safe to resurface my cylinder head?

Post by GPz11 »

Sure it's safe, but does it need it is the more important question.
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Re: It is safe to resurface my cylinder head?

Post by xrattiracer »

the same shop that would do the surfacing can tell you if it actually needs it too.
I'm with the person that said they always need it.
86 Silver XR4Ti. 'squirted. 12.7@111
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Re: It is safe to resurface my cylinder head?

Post by KhanTyranitar »

I would say if its a stock finish now, then yes. The stock finish is quite coarse. I'm surprised they don't blow gaskets more often than they do. I have my block deck resurfaced too. But then again, both my motors were complete rebuilds. Certainly there is a limit for how much can be removed, but I think these heads could be rebuilt multiple times before that would become an issue, depending on how much material had to be removed to achieve a flat and smooth surface.
Last edited by KhanTyranitar on Sat Apr 05, 2014 9:59 am, edited 1 time in total.
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Re: It is safe to resurface my cylinder head?

Post by merk23literturbo »

There is some info in this post for you:

viewtopic.php?f=30&t=26711
Pictures, projects and cool stuff here: http://tinyurl.com/psyuhej
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Re: It is safe to resurface my cylinder head?

Post by Larry Velk »

Relative to the referred post - I recall that 1989 heads had different treatment to the exhaust vales and/or seats. They DO have a different casting number. This I personally confirmed with our '89 vis-vis our 1988.
One of our '88's had a 0.005" "skim cut" after machine work. This was done at a local speed shop.
As an aside, the reason I took the head off was a MISSING 'flame ring' around the oil feed on the original Ford gasket!! It held for about 70k, started to leak and I pulled the head at maybe 110k due to a worsening oil leak. All wonderful after repair. Leak was from, of course, the same area as the pressure switch and turbo cooler line, so the diagnosis was very astute on my part (!). The fiber held pressure until it eventually eroded. You obviously need the metal emboss to hold the 60 or so psi over many years.
'86 928, black, 5sp, red full leather, 55k
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'91 FZR 1000
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'89 XR, red family car
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