low compression in bank 2, bank 1 is perfectly fine

So i am having a similar problem. cylinders 1,2,3 and 4 are all running about 165psi. 5,6,7 and 8 are all running right at 180. Like a fool, i did not run a compression test before i did the timing chains, guides and sprockets as the motor was out of the car when i decided to do them. I am positive that i followed the procedure correctly and the marks on the chains lined up with the marks on the sprockets when i was complete. I even used the cam holding tools recommended by the manual. So before i go tearing down the front of the motor looking to see if one of the cams possibly jumped a tooth, is it possible i got a defective sprocket for one of the cams? Is there something else i am missing that would have the whole bank running low? Am i over thinking this? Thanks!

johno71 said:

I am positive that i followed the procedure correctly and the marks on the chains lined up with the marks on the sprockets when i was complete.

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Did you take pictures? Why is this important? Because it has happened more than once that the cam sensor "bump" on the left hand cam was mistaken for a timing "dot" resulting in an out of time for the left hand bank.

Obviously if the incorrect timing mark has been used the person doing the work believes they have done it correctly (but in fact not).

wmburns said:

Did you take pictures? Why is this important? Because it has happened more than once that the cam sensor "bump" on the left hand cam was mistaken for a timing "dot" resulting in an out of time for the left hand bank.

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I did take pictures, unfortunately i took them after i stuck the harmonic balancer back on so you cant see the dot on the bottom, but you can see plain as day the dot in the pic on the cams.

Looks good from what I can see in the pic. Obviously without being able to see the crank, we can't double check the crank dot. However based upon what can be seen in the picture the motor would be in time left to right. If out of time the whole motor would be out of time.

You don't have to tear down the front of the motor. It's possible to check timing by just removing the value covers. The down side of this method is you may have to turn the motor over by hand a TON of times in order to get the marked link and the cam dot to line up at the same time. But if you can see both cams still lining up between the dark links and the dots, IMO it's safe to conclude that the motor has not slipped time since you installed the chains.

Thanks,
yeah, i'm starting to lean towards slop in the cam gears them selfs. I have read a bunch of articles like this http://www.mustangandfords.com/how-to/engine/mmfp-0612-ford-mod-motor-cam-timing/ to where the cams were not perfectly timed from the factory. I wish i would have read this article before the motor went back in the car. I did just put a turbo on this motor so i was double checking things before i head to the dyno. There is a lot of things to move in order to open the front of the motor back up. I don't plan to keep this motor in the car long term anyway. I'm already thinking about forged internals and more boost! I wan't to use this motor as the learning curve for the real motor.