Valve Adjust w/ Man-A-Fre cam

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Apr 9, 2012
1991 FJ80 w/ 3FE. I have been through the forums back and forth and have not seen anything dealing with valve lash adjustment when an after market cam has been installed. Just finished a rebuild and, while markedly better, the low end (why I got the cam) is lacking as well as suffering from low vacuum (3FE does not like that). I choose the Man-A-Fre cam from comments on the forum, but now I am wondering if I made a good choice. Dealing with Man-a-Fre tech support (lower case for a reason), they said that a per cylinder TDC valve lash adjustment was required...nothing more concerning the process.

So, having verified that the cam was installed correctly (timing cover removed), compression check is good, TPS adjusted, o2 sensors, MAF.... all operating fine, smoke test without any vacuum leaks, I am left with valve lash creating an internal vacuum leak. Open for other suggestions...

Can anyone describe, or point me towards a method of valve lash adjustment that is as described above OR will work with an aftermarket cam? Man-a-Fre mentioned the FSM method does not cut it here and I will agree with that.

I have read about the EOIC method but am not convinced. Has anyone tried this?

Thanks in advance!
I've always adjusted my Delta regrind following the FSM method and specs :meh:

How have you set your timing? That will certainly effect vacuum and seat of pants dyno numbers, although you won't get as much vacuum as you did with a stock cam due to the increased duration.
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Got it.... I think.

So, I got a call from a local tractor repair guy last night and explained the issue. He suggested the following;mark the balancer at 120's (tdc as reference). Rotate through the firing order and set lash at TDC on each cylinder. I went back through again and used the EOIC to fine tune for overlap. Seems to have helped.

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