cost for chain tensioner upgrade
 

I have a 1978 targa with 107000 miles. I have been advised to upgrade the tensioners to the turbo style. The 101 projects book suggests this is a 5 hr job. Well maybe for someone who has done it before. I see prices for the parts at $900 but my first quotes were $2300 and $2500. What is reasonable in northern california.
Also at what mileage should I be concerned?

I think the parts cost is more like $1500 nowadays. I am going to have to do my own.

tensioner parts
 

Check amazon vertex for $819

Ah, you should be concerned 50,000 miles ago.

You can buy genuine Porsche from Pelican for $786.

I must be thinking of the Carerra chain tensioner upgrade.

Or do the guards:

http://forums.pelicanparts.com/porsche-911-technical-forum/878767-engine-near-death-experience-best-21-ever-spent.html

Chain tensioner guards with updated idler arms would be a great option. See the Supertec website for information on re bushing and modifying your idler arms for a reasonable price. The tensioner guards should be a required addition to any early 911.