Cracked Tfs Head

Discussion in 'Fox 5.0 Mustang Tech' started by dcurtis, Sep 22, 2013.


  1. dcurtis

    dcurtis Active Member

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    Well, blew the stock aod transmission a few months ago and with kids and work just kinda put the stang away for a while, finally decided to get her going again and bought a built aod for it, I decided to pull the engine and tranny so I could go ahead and replace the rods, mains, and head gaskets.
    Well got the top end off and found this, is this repairable? Engine was running perfect with no issues, glad I found it though.
    Any suggestions? Would it be easier to just buy a bare head and transfer my valve train over?
     

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  2. 84Ttop

    84Ttop They make new pistons every day, so why worry? SN Certified Technician Mod Dude

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    This was a common problem with some of the original casting from TFS. I would have the head pressure checked, you may be surprised to find that it doesn't leak at all. I have seen these with visable cracks worse than this and they seal with no trouble. Either way that is very repairable and the repair would typically be far cheaper than replacing the whole cylinder head.
     
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  3. dcurtis

    dcurtis Active Member

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    They are the fast as cast 170cc version, dual spring, 10° locks, anyway after some sanding, very fine paper and no pressure it seems to be disappearing, gonna go ahead and take them to machine shop and have it checked, hopefully just have them milled a bit and re-install. Compression should still be OK, running srp flat top 2 valve relief, 58cc chambers, 347.
     
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  4. Rick 91GT

    Rick 91GT SN Certified Technician Site Sponsor

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    Weld them up....

    Sent from my XT907 using Tapatalk 2
     
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  5. dcurtis

    dcurtis Active Member

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    Rick, weren't you running the same n51hr cam? What size stall were you running with it, if you were auto, I'm running a tci right now but want a bit higher, I think its 28-3000
     
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  6. Rick 91GT

    Rick 91GT SN Certified Technician Site Sponsor

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    I had a n61 in that old 302 combo...t5.

    How high are you revving? What rear gear and tire do you run?

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  7. dcurtis

    dcurtis Active Member

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    Right now I have to feather the hell out of it to keep out of the factory 6250 limiter, it hits it damn quick, not sure in inches but running 255/60-15's with 373 gear.
     
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  8. dcurtis

    dcurtis Active Member

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    When it will hook it is still pulling very hard at the limiter, would like to raise it a bit, maybe 6500-6700, still on factory block though.
     
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  9. Rick 91GT

    Rick 91GT SN Certified Technician Site Sponsor

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    I made power up to about 6400rpm on my combo and shifted 6800-7000 launched at 5800-6000 with a 3:73 and a 26 x 10 ET Street. The car really needed 4:30 gears as I was only trapping around 5300 @ 117mph. However I had a 175 shot and was trapping high 6000s @ 137mph.

    Factory bottom end and a t5...lol car made 540rwhp and 742rwtq on the bottle.

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