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How was the compression test done ? The SVT is a high compression engine but with the VCT and doing a compression test the compression test wont be very high compared to a normal engine compression test

Why are you doing a compression test , how does the car feel under power ?

Tom
 

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^^^^ Yup

Consistent is a plus, easy to get low numbers depending on how it's done.
 

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Discussion Starter #4
I used a gauge threaded into the spark plug hole. Car won't start. Has fuel and spark, but low compression. Tom I called you about a month ago about the timing issue, and it went pretty smooth after talking to a couple ford mechanics and printing stuff out. I also put a new gasket on the head. Everything was done right though. I'm completely at a loss. I miss driving this thing. :/
 

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Why was the belt replaced? Exhaust valves love the pistons. Even an over rev or two can cause enough for low compression.
 

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Discussion Starter #7
The car overheated and warped the head about 8 mils. I got the head milled and put a MLS gasket back on the head. Got everything back together and times and now it won't start and low compression.
 

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The one thing I didn't do was completely check the bottom end. It got hot enough to warp the head. As soon as I felt a loos of power I pulled over and cut the engine off.
 

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A leak down test will tell you if it is a timing belt installation error or compression going past rings/pistons , thats what I would do or have done next

Tom
 

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I'm the one to ask the silly questions to make sure nothing's missed.

When doing the compression test, was it cranked with the throttle open until the gauge stopped rising?

Limited cranking or throttle closed can affect numerical results greatly.
 

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4 cycle engine should only be cranked 4 cycles , 2 cycle engines 2 cycles for a compression test

As long as all 4 Cyl were done with the throttle closed then its fine

Ideally Sailor is correct a warm engine , throttle open and cranking the engine 4 revolutions is the proper way to do a compression test

Tom
 

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Yah, silly question as described.

Don't want to assume anything since I've seen low compression reported before that turned out to be fine. Couple turns with the throttle closed yielding low numbers.
 
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