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Compression spec for a TC96

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Old 01-16-2013, 11:50 AM
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Default Compression spec for a TC96

What's the compression on a stock TC96? Manual said 100psi 10% variation between front and rear cylinders. Did a search most ppl said between 175-185psi. I have checked mine yesterday, low miles motor, no oil burning, I only get 150 and 155psi, does it seem low? I currently installed tw-555 cams and have some running problems, worry about the cam timing slightly off. Please advice!
Thanks Alex
 
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Old 01-16-2013, 03:24 PM
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For my 2008 with stock cams, my rear and front readings were both the same:

Gauge reading at the end of the first compression stroke : over 150 psi
Gauge reading at the end of the last compression stroke : 200 psi.

My touring manual says to turn through 5-7 full compression strokes and take readings. Final readings should be at least 125 psi and no more than a 10% variance between both cylinders.

So it appears that you are within limits.
 
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Old 01-16-2013, 04:23 PM
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Originally Posted by 128auto
What's the compression on a stock TC96? Manual said 100psi 10% variation between front and rear cylinders. Did a search most ppl said between 175-185psi. I have checked mine yesterday, low miles motor, no oil burning, I only get 150 and 155psi, does it seem low? I currently installed tw-555 cams and have some running problems, worry about the cam timing slightly off. Please advice!
Thanks Alex
IMO those cams desire a compression boost. Dont know why guys put em in their stock 96's. I would even have a hard time sticking them in a 103 as well unless I was gonna do some motor work but that's just me. But they are kinda the new sticks on the block.

Although you are most likely within range you should know that youre actually dropping your compression with those cams because your intake closing has now changed.

If a stock 96 runs 200 cold crank compression at sea level, with those 555's you are probably moving it down to 180 and youre static compression will change from 9.5:1 to about 8.8:1

Just puttin it out there
 
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