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Alan L Alan L is offline
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Join Date: Apr 2006
Location: New Zealand
Posts: 3,185
'Have you removed the spark plugs after driving and seen a difference in the color or possible oil deposits? Thats better than trying to judge AFR mixtures from the insides of the header primary tubes.'

Jim, I had a look at #3 and #4 now - the easy ones. They dont quite show the same as the respective headers tubes. The centre electrode in both cases is dark tan. The outer electrode body in both cases are black. But you are right - I should check after straight off the track. It is just that I have just seen this weird stuff for the first time since bringing it home from track. I did leakdowns/compressions about 3 mths ago - before I re ringed it and they are good. I thought I may have had damaged rings at one point, so pulled it down.
Correct - GHL and I cut the heat boxes off - this was before I ordered a set of Brian's tuned headers - which are in the post? I should have left the heat boxes on for re sale - but I didn't know 3 mths ago Brian was going to sell me a set of his headers.
I dont know anything about port sealing rings - I just have the usual gaskets on the heads - am I missing something here?
Brian, if it was the fuel head, what would you have in mind. I had a lot of trouble with the head, but am still a little suspicious about it and the PO. For instance on boost I cannot get rid of excess fuel - I would like my AFRs a bit higher - in the low 12s, but can't get there. I have had to put my old OEM WUR back on for the moment while UT tweek my DWUR. I have had to blank off the boost port on the WUR - it is the only way I can moderate the fuel at WOT to sensible AFRs - 11.8-12. So, I do wonder about what may have been done to the fuel head previously.
I had it apart, and to the eye, cannot see any modified slits. If it had Y slits, it would make more sense - mine dumps enough fuel without a 0.5 bar CP drop, at boost and WOT , but below boost it is too lean - which makes it a pig to drive on track halfway around a corner. But that is another story.
I have a mate with an IR pyrometer - uses for tyre temps. Can borrow - but probably only measuring idle temps?
Alan
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83 SC, 82 930 (track) - Stock except for RarlyL8 race headers, RarlyL8 Zork, K27-7006, 22/28 T bars, 007 Fuel head, short 3&4 gears, NGK AFR, Greddy EBC (on the slippery slope), Wevo engine mounts, ERP rear camber adjust and mono balls, Tarret front monoball camber adjust, Elgin cams, 38mm ported heads, 964 IC. 380rwhp @ 0.8bar Apart from above, bone stock:-)
Old 11-16-2011, 11:14 AM
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