SeanR

You guys realize that even on the factory tensioner that the screw is never in the same place when properly tensioned, each car is different. Should be no surprise that the extension on the PKT is different on each car also.

Cosmo Kramer

Absolutely, and that screw has a much longer range then 11 mm to account for variances.

Sean, you would be the best person to answer this question because you probably have installed more PKT systems than anyone else on this board. Have you ever had to drill a T/D because of excessive piston extension? If so what is the frequency?

SeanR

Never, nor would I. If the PKT wouldn't install with in the extension spec, I'd put a factory tensioner back on and explain why. I've also not encountered a PKT out of spec and these threads concern me greatly as I only get to see about 3/4 the cars I've installed them on again. I'd be willing to bet a good 25% of my business the cars are shipped in and back out due to the wrenches local to the customers have no clue what they are looking at when it comes to a 928.

GregBBRD

Sean, thanks for joining in.

I'm very concerned about how I'm going to set the cam timing on this new GT engine I'm building with the Portensioner.

Having to go back in 2 times, once after the engine runs initially and then again in 1000 miles (per Ken's instructions) is not only very inefficient, but going to be expensive for the client.

Certainly you have replaced cam gears and had to re-set cam timing on many of your Portensioner installs.

Would you be willing to share what you do to initially set the cam timing correctly?

bureau13

I'm confused by this as well. The number of teeth between the various gears isn't changing (it better not!) so why would timing change more than with a stock tensioner?

Lizard928

It wouldn't. It would be set as per the manual and left.
The belt stretch would be roughly the same with the PKT vs factory.

Although, why not set it as per the factory, verify where it is with the 32V'er and then after 1000 miles reset to the known location with the 32V'er?

PorKen

OMG. Where does he get this stuff?


Nowhere in the PKT manual does it say to check the cam timing after 1000 miles.

That's the point of the PKT - to not be like the stock tensioner, no 're-tensioning' required.

If you change the cam timing (with a PK32V'r) then if you really want to be precise then check it again after the belt has seasoned. If you follow the directions to set the INITIAL timing with a new belt to 0, 0 then after 1K miles the 1-4 side will usually retard to make -2, 0 which is what the PK32V'r indicates as the factory setup.

GregBBRD

Someone is loosing it, here.....and it's not me.

Direct quote from your post #53....in this thread. Not something taken out of context, but printed the entire thing, here....

"Either by dial indicator or using the PK32V'r I found that the timing cannot repeatably set or reset unless the engine has been spun with the starter to settle the belt.

Set the cams in the middle of the slots. After the engine is installed use a PK32V'r and PKBumpstick.

If the belt is new, after 1000 miles you will want to check the timing again. If you use the tips in the PK32V'r manual the seasoned measurement will likely be close enough for most folks (±1°)."






You do know what you say, a couple days after you say it, right?

Because like I said above, this is cumbersome, for me and expensive for the client!

SeanR

Having set and checked the timing with the 32vr tool on several cars, I've not had to reset the cam timing, they stayed right where I initially set them.

Have you had different results?

PorKen

Emphasis added. Because: proven unable to follow directions.

I do hope you are checking actual cam timing after 1K miles after using a dial indicator...especially if you 'set' it on an engine stand.


Thanks for the sales pitch, BTW! As everyone knows that is yet another reason why I developed the PKT: no going back in after 1500 miles. Pointless, expensive, and time consuming as you say.

bureau13

To be fair, I was confused by that too. I was grumbling to myself that nobody had told me I'd have to go in and recheck that. Glad to know I don't :-)

PorKen

Some people find it fun to check their cam timing...









(with a PK32V'r )

drwhosc

Installed mine 5 years ago, love it. doing great. Due for a check this summer. I realize the possibility of a catastrophic failure, but it is a design flaw from the folks at zuffenhausen that we have to thank.

Live the 928 life, live on the edge.... Just have to deal with all the things that can take out an engine. The list is growing...

Hilton

In the passive-aggressive versus aggressive war.. I think aggressive looks better.

Imo000

Most people would interpret the "you would want to" as you need to do it. Hiding behind carefully choose words, are we?