New style cam chain tensioner?

[guest]

Mike, have you had the oppotunity to see any of the new tensioners with some miles on them yet? I am going back and forth on wether to do a retro fit of the new style tensioners or go with gear drives. If the new style look like they are wearing better I would lean towards them because with my luck I will have one of the cranks with too much run out. thanks guest

[Mike]

We have not yet seen enough miles but they are similar to those used for the counterbalancer chain in B motors and these have done extremely well with virtually no wear after 10's of thousands of miles.
Thanks, Mike

[Talon]

Mike, how ofter do you run into crank runout problems, I want to go with gears, but I'd hate to order a gear cam kit and have my crank to far out after I get the cams!! :(

[Talon]

Oh by the way I have an 05 88".

[Mike]

We check runout's routinely and often find them to be .0015-.004. When it's a problem depends on who you talk to. Bob Wood, I believe, says more than .0015 should be corrected. The problem is how? You will not be able to get gear backlash down to -.001 with much more than .0015 runout on the crank. So then, what is acceptable? I do not get too excited until we are in the +.006 area (a lot from the cam plate bushing's point of view, along with oil pressure losses). There will be those who'll say this is way too much.

It's tough to recommend complete engine teardowns and replacement or corrected (not easy to do) cranks to customers who came in for a cam/gear drive change. You also get to correct all the other things you'll find not quite right in the process so then it becomes a motor rebuild pretty fast! It's a bit of a judgement call and each engine builder will have their own critical number but it will still come down to what customers are willing to accept and at what point is it truely a problem vs. an annoyance.
Mike