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Discussion Starter #1
OK, here's to story.

'89 5-0h. I purchase it used a few years ago, essentially stock, very clean. However, it always had a bit of a "flat" spot in the idle and while cruising. Nothing bad that you could feel, but you could definitely hear it. I did the tune-up thing with new plugs, wires, cap & rotor. No change. I purchased a Jacobs Ultra Team ignition system....ran a lot better, but it was still there.

So, this Spring, I consult with Ed Curtis at FTI. I end up with essentially his version of a Pure Street combo. I get this thing dialed in as best I can with the timing, fuel pressure, air/fuel ratio, etc. Guess what...this intermittent miss is still there. However, with the new combo, it is rather obnoxious. It's there at idle and especially anything above 2500 rpm...but gets worse with increasing rpm so I haven't pushed it. It hasn't made its way out of the garage yet. I have yet another set of Autolite plugs, new MSD cap 'n rotor, new Taylor 10.5mm race wires, and my Jacobs Ultra Team ignition.

The engine has never used oil and there was no ring groove when I pulled the heads. I haven't checked compression in the cylinders, but given this, I think it is OK. When I was setting my timing, I noticed my timing light flash erratically and you could hear the subtle change in idle when this happened.

Any guideance on how to track this pesky thing down? I am about ready to consider taking it to a shop to have someone else look at it (I know, blasphamy, but I am a little frustrated).:confused:
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