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Timing: How much tension is the right tension?

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Old 10-02-2017, 05:09 AM
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MA7008O
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Default Timing: How much tension is the right tension?

Hello there,

I am in the timing process, and have come up with the question: how much tension is the right tension?

I have read a lot, but still have the doubt.

I am using a regular homemade tensioner as many of you have done. I set everything up correctly, but, am I applying the right tension?

Please look at his video from a member. Using a homemade tensioner, tension affects the reading on the dial:

He also compares the Stomski Tool vs Stock Tensioner (
), with minimal differences.

Any inputs or guidance that you can offer me would be greatly appreciated. It’s just so scary to go on, assemble the rest of the engine and fire it up without been sure about this.

One more thing: is it a problem to do the timing setup with all the rockers installed instead of just input for cylinders 1 and 4?

Thanks gain for your much-appreciated help.

Sincerely,
Old 10-02-2017, 09:53 AM
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Rocket Rob
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I'm not an expert, I've only done one engine but when I did my timing, I used a hand-made tensioner, z-block and dial indicator. I had difficulty getting repeatable results. I feel that a lot of my problem was the variances in how the z-block got remounted as I switched from side to side. I then bought a pair of Stomki tensioners, dial indicators and holders. It was very easy to get repeatable results and I knew that both cams were set to the same settings.

In my head, having the same settings side to side is the key to a balanced running engine. I'll be curious to hear what others have to say.
Old 10-04-2017, 04:07 AM
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Originally Posted by Rocket Rob
I'm not an expert, I've only done one engine but when I did my timing, I used a hand-made tensioner, z-block and dial indicator. I had difficulty getting repeatable results. I feel that a lot of my problem was the variances in how the z-block got remounted as I switched from side to side. I then bought a pair of Stomki tensioners, dial indicators and holders. It was very easy to get repeatable results and I knew that both cams were set to the same settings.

In my head, having the same settings side to side is the key to a balanced running engine. I'll be curious to hear what others have to say.
Well, maybe no one has much to tell.
One question: do you still have the Stomki tensioners? If so, could you please measure the distance that they expand form the surface matching the case (were the gasket will go) to the extreme?
Thanks,
Old 10-04-2017, 08:52 AM
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Rocket Rob
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Yes, I do. I can measure the distance when I get home tonight.
Old 10-04-2017, 09:22 AM
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robt964
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I may be wrong but I'm not sure that measurement will help you. I've never inspected a stomki tensioner but from videos and descriptions I've read, when you tighten down the adjuster, you are actually loading against a spring which is pushing down on the rod that then presses against the ramp. The adjuster is tightened down until the two washers meet. At this point the spring has the required preload and pressure on the ramp. Is this description accurate Rob?
Old 10-04-2017, 09:39 AM
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Rocket Rob
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Originally Posted by robt964
I may be wrong but I'm not sure that measurement will help you. I've never inspected a stomki tensioner but from videos and descriptions I've read, when you tighten down the adjuster, you are actually loading against a spring which is pushing down on the rod that then presses against the ramp. The adjuster is tightened down until the two washers meet. At this point the spring has the required preload and pressure on the ramp. Is this description accurate Rob?
Yes, that's my understanding. The marked distance provides a set pre-load of pressure.
Old 10-04-2017, 10:51 AM
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In that case yes, the measurements are worthless.

I thought that they had a preset distance and were rigid, so knowing the distance would help.

Thanks anyway!!!
Old 10-04-2017, 10:55 AM
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Any inputs on question about if all rockers can be installed prior to timing or just the intake number 1 and later number 4?

Thanks gain for your much-appreciated help.

Sincerely,
Old 10-04-2017, 11:55 AM
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I can see no issues why not given that you can check and adjust the timing on a complete assembled engine. Provided you assemble with cam in roughly the right ball-park position
Old 10-04-2017, 12:14 PM
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I set my timing with rockers on #1 & 4 intakes only. The rest of the rockers were installed afterwards. But I doubt it will affect your settings if you have them all installed and properly adjusted.
Old 10-04-2017, 02:45 PM
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dutchcrunch
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Default timing

1.26 is at overlap. on another note, unless you set the the z1 mark on the pulley to true top dead center of the crank your gonna be off. stomki should have told you that. on the pulley install before you tighten it down look how mush you can turn from left to right and you will see that it can make a difference.
Old 10-04-2017, 02:51 PM
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Default tensioner

the factory tensioner are not a solid tensioner, there is a calibrated spring with a set dimension you dial in to a mark..... this is to simulate how the engine will run with tensioners in place. that's why solid tensioners tool are not meant to be used. Porsche design the tool not me
Old 10-05-2017, 03:56 AM
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On the second video that I posted, He compares the Stomski Tool vs Stock Tensioner.

He first sets the timing with the Stomski tool to exactly 1,26. Then he removes the Stomski tool and installs the stock tensioner, and gets a reading of 1,28.

I wonder if this is close enough. I mean, I believe 1,28 is within specifications, so the stock tensioners maybe just used.

Any inputs on this?

Thanks again!!!
Old 10-05-2017, 08:43 AM
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JohnK964
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Originally Posted by Rocket Rob
I set my timing with rockers on #1 & 4 intakes only. The rest of the rockers were installed afterwards. But I doubt it will affect your settings if you have them all installed and properly adjusted.
I did mine the same as Rob but then rechecked each time I added another set of rockers was paranoid and checked it a few more times then was afraid to start engine for two weeeks😁 Finally started it every thing was fine👍
Old 10-05-2017, 10:54 AM
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Originally Posted by JohnK964
I did mine the same as Rob but then rechecked each time I added another set of rockers was paranoid and checked it a few more times then was afraid to start engine for two weeeks😁 Finally started it every thing was fine👍
Afraid just two weeks???
I rea done fellow member that was afraid of reving the engine for a few months….



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