LT5 cam timing

[creative sewer]

Does anyone have pictures or a DVD on cam timing? I've read everything I can and don't get it. I'm missing something between finding TDC on the crank and the dial indicator on the cams. HELP!!!

[bdw18_123]

You should post this in the "ZR-1 Technical Postings" section, you'll get a better response.

Have you read through the cam timing info put together by Mark Haibeck? You can download the PDF file from his website, here is the link:

http://www.zr1specialist.com/HAT%20Web/articles/timing_camshafts.htm

There are also lots of links to cam timing info in forum member Dynomite's "Solutions" thread (a sticky at the top of the "ZR-1 Technical Postings" section).
Link: http://www.zr1.net/forum/showthread.php?t=11619

Here is a cut-and-paste from it:

CAMSHAFT TIMING USING PINS
Camshaft timing http://www.zr1.net/forum/showthread.php?t=9813
Camshaft timing event picture http://www.zr1.net/forum/showpost.ph...5&postcount=16 (http://www.zr1.net/forum/showpost.php?p=80645&postcount=16)
Camshaft timing using pins http://www.zr1.net/forum/showpost.ph...7&postcount=66 (http://www.zr1.net/forum/showpost.php?p=78127&postcount=66)
Resetting timing chain tensioner http://www.zr1.net/forum/showpost.ph...1&postcount=18 (http://www.zr1.net/forum/showpost.php?p=87521&postcount=18)

CAMSHAFT TIMING USING DEGREE WHEEL
Top dead center TDC http://www.zr1.net/forum/showpost.ph...3&postcount=19 (http://www.zr1.net/forum/showpost.php?p=87523&postcount=19)
Marc Haibeck camshaft timing http://www.zr1.net/forum/showpost.ph...5&postcount=21 (http://www.zr1.net/forum/showpost.php?p=87525&postcount=21)
Camshaft timing details http://www.zr1.net/forum/showpost.ph...4&postcount=20 (http://www.zr1.net/forum/showpost.php?p=87524&postcount=20)
Camshaft timing optimum deg http://www.zr1.net/forum/showpost.ph...7&postcount=12 (http://www.zr1.net/forum/showpost.php?p=80627&postcount=12)
Degree wheel http://www.zr1.net/forum/showpost.ph...2&postcount=18 (http://www.zr1.net/forum/showpost.php?p=87522&postcount=18)
Setting up degree wheel http://www.zr1.net/forum/showpost.ph...41&postcount=7 (http://www.zr1.net/forum/showpost.php?p=78241&postcount=7)

[creative sewer]

Thanks, I'm new at this thread stuff. I've resent it on the tec side. I've already been through all those threads and just don't get it. There's just something I don't conect.

[creative sewer]

I think I'm on the right track. In stock form before taking the cams out this what I got: #1 cyl Intake 120, #1 Exhaust 110, #6 Intake 113, #6 Exhaust 118. I tried to verify this by puting the cam pins in the holes at 51 Degrees. One cam pin went in at 46 Deg, one at 51 Deg, one at 55 Deg and one at 60 Deg. There is some slack which can make up some difference but it's a sign nothing is in sink? Can motors run fairley well when the cam timing is that far off? (this one did?)

[Dynomite]

I think I'm on the right track. In stock form before taking the cams out this what I got: #1 cyl Intake 120, #1 Exhaust 110, (#1, #3, #5, #7 should all be identical )#6 Intake 113, #6 Exhaust 118 (#2, #4, #6, #8 should all be identical). I tried to verify this by puting the cam pins in the holes at 51 Degrees. One cam pin went in at 46 Deg, one at 51 Deg, one at 55 Deg and one at 60 Deg. There is some slack which can make up some difference but it's a sign nothing is in sink? Can motors run fairley well when the cam timing is that far off? (this one did?)

Marc Haibeck suggests there is about 3 deg of play (6 deg measured at the crankshaft) between the sprocket timing plate flat (vernier plate) and camshaft flat (90'-92').

That means after you have pinned the camshaft, the crankshaft can move 6 deg due to the play in the venier plate as you tighten the camshaft bolt.

When you dropped the pins as cited above it is assuming the slack was out of the timing chain (using the manual chain tensioners) as you rotated the crankshaft (equally for all four cams) as you noted your crankshaft degrees.

Having pins drop in at 46 deg and 51 deg on one bank and 55 deg and 60 deg on the other bank would not be so unusual depending on how you made sure the timing chain slack was accounted for (It does sound a bit sloppy original timing on each individual bank). Also as I recall, one bank tends to stretch or wear a bit more than the other bank in regard to camshaft timing (I forget the reason) :mrgreen:

It might be hard to tell change in performance unless someone else drove your Z as you have become used to its performance at that camshaft timing (unless of course you put it on a Dyno).