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Topic: Stock tach swinging (Read 802 times) previous topic - next topic

Stock tach swinging

Got a new trans installed - slippage seems to be much better with anywhere between 16% slippage at 4k, 7% at 5k, and 5% at 6k (3k PI 9.5" converter). Now I've moved onto my engine. I've had a slight misfire for what seems like an eternity - I believe I had the same issues with different heads, lifters, pushrods, intake, and rocker arms. The parts that haven't changed have been the shortblock, '89 HO camshaft, and distributor/some sensors. I probably had a slight misfire for the 30k miles I put on the shortblock since the time it was rebuilt.

Here's a video of what's happening at WOT: https://www.youtube.com/watch?v=LiD_DhcINGI&feature=youtu.be

On cold start especially, occasionally my tach will twitch, but almost every time I start the car cold, speedo will swing between 20-30mph, until the engine heats up. I'm going to try swapping the distributor/TFI since that has been a constant.

Has anyone ever seen this behavior? In the (uphill) WOT run above, I could feel the engine starting to miss frequently. I'm going to be reviewing the datalogs to get a better idea of what was happening there.
1988 Thunderbird Sport