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My head was warped, I got it skimmed flat, got 8 thou taken off it. Now when I lay a straightedge (a good one!) along the cam journals the middle three are about 5 thou lower than the ones at each end :( I couldn't find any specs for the max deviation allowed in the TRSM (it tells you the max camshaft runout) ; is this head still usable, does it need some sort of remedial work, or is it scrap?

Anyone ever priced a new head casting from Toyota?
 

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Personally, I dont believe that camshaft clearances are alltogether too critical. However, you wouldnt really want to bend the camshaft as you torque it down because that will cause A TON of wear on the journals.

I think you should just purchase a flapper wheel that will sand the entire ID of the journals on the head, and grind it down with some lubricant. Keep the die-grinder in the middle of the journal so that the flapper wheel stays centered. The link below will explain what im talking about. Just get it close - .005" isnt really TERRIBLE, but i think the hand-grind would minimize the effects of the warpage. I had to do this on my head because the dumbass that hottanked and cleaned my head bead blasted the journals. Im sure that more was removed from MY head than yours will have to be, and I have no adverse effects, oil pressure is fine.

http://www.sa-motorsports.com/cat/p25.htm#FW
 

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Yep, I understand what you're saying there and it makes sense. Won't I lose some valve lift though if I make the journals bigger? As the cam spins, won't it move up inside the journal when it should be pushing the valve down?
 

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I was reading through the Toyota service manual for my 88 last night and what's interesting is they say if the head is warped more than .003 replace the head. They don't even recommend resurfacing. Mine was cut .012 and the block was .010. I run an HKS metal 1.2 gasket and have had zero problems. I also lapped both the head and the block. Adam I would put a dial indicator on the cam when I torqued the caps down and see how much the cam actually deflected when you tightened it up. I'll look for the spec's tomorrow and if I find anything I'll post it.
 

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Adam W said:
Yep, I understand what you're saying there and it makes sense. Won't I lose some valve lift though if I make the journals bigger? As the cam spins, won't it move up inside the journal when it should be pushing the valve down?
I dont think anything significant will be affected. Mine runs great except for another problem unrelated to this.
 
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