LN IMS Upgrade

[kbrandsma]

I'm working with a friend on his MY00 Boxster S that recently had a LN IMS Upgrade by a qualified Indy. The mechanic did not use the Camshaft lock tools that came with the kit. What if any should we be concerned with or be looking for to determine any faults with this installation? Can Durametric read any Actual Values that might help?

Thanks in advance!

[logray]

If the car has not been started yet you can pull the cam bearing caps to verify timing.

If the car has been started validate the camshaft deviation values for bank 1 and bank 2 are 0 +/- 4 degrees.

[JFP in PA]

I'm working with a friend on his MY00 Boxster S that recently had a LN IMS Upgrade by a qualified Indy. The mechanic did not use the Camshaft lock tools that came with the kit. What if any should we be concerned with or be looking for to determine any faults with this installation? Can Durametric read any Actual Values that might help?

Thanks in advance!

Normally, we like to run a profile on the Durametric prior and post installation; just to verify that the cams are were they belong.

The car in question is a five chain motor, which is more tolerant of IMS bearing install screw ups, but not immune. Logray is on the money as far as looking at the cams, but if you have access to a Durametric, I would hook it up and look at the cam deviation values, both of which should be rock steady and idle and +/- 6 degrees. The actual values are always an odd set of numbers, but they need to be in that +/- 6 degree range. The Durametric is a much quicker and a very accurate way to check this out.

In the future, if an Indy suggests "we don't need no cam locking tools", run…………..

[logray]

Hey JFP, isn't the Boxster +/- 4 degrees, or maybe I'm not remembering right... I thought the 3.4L and above was 6 degrees. Could be wrong of course.

edit: grammar corrections.

Edited September 22, 2011 by logray

[JFP in PA]

As far as I know, all M96/97 engines are +/- 6 degrees.

[logray]

Page 69 of Diagnosis to 45 for Boxster 986 says +/- 4 degrees. Interesting.

Edited September 21, 2011 by logray

[Jager]

Here is a picture of my cam deviation post IMS bearing upgrade. Prior to the bearing replacement I had .60 degrees difference deviation between bank 1 and bank 2. Another improvement was the idle, it became smoother and it increased ~150 RPM.

Edited September 22, 2011 by Loren
made image viewable here

[JFP in PA]

Page 69 of Diagnosis to 45 for Boxster 986 says +/- 4 degrees. Interesting.

I think a couple of things changed; originally, the early five chain motors were +/- 4 degrees, and were pretty good at meeting and holding the range. The switch to the three chain design and the later VarioCam Plus seems to cause more cam deviation, so the value was moved. In reality, early or late motors seem to do just fine as long as they stay within the +/- 6 range, so a lot of dealers and shops started using that as the “default” range for everything.

[logray]

Interesting JFP as always thank you!

It is also interesting that the original 996 workshop manual says zero +/- 6 degrees.... of course that was a certain number of years after the Boxster had been produced.