PlantMan

I have been paying more attention to the cars I look at for purchase (78-83SC)consideration to insure that they have tensioners installed.

Should I be to concerned if a particular car does not have the upgrade? I would hate to pass on a nice car just because it has not been upgraded.

Should I budget atleast $1000 to upgrade it myself (DIY)?

I understand the reason for the tensioners.

Someone in another thread said to walk away from a car without the upgrade. I would copy the thread link but can't seem to find it in the archives.

Thanks,

Peter Zimmermann

If everything else about a particular car fits your needs, it's no big deal if the tensioners have not been upgraded. That said, a professional PPI should always be done, and negotiation with a seller regarding the cost of a tensioner upgrade is acceptable. And then you can schedule the upgrade with your choice of mechanic, or prepare to do it yourself. To avoid possible painfully expensive surprises, be sure that the PPI includes a rocker cover off inspection of the cams (pitted lobes) and cylinder head studs (broken).

https://rennlist.com/forums/911-foru...immermann.html

theiceman

The only cavaet i would add to Petes advice is that is the guy has not spent the money on what at least I would consider a "mandatory" upgrqde , what else hasn't he spent the money on in maintanance ... just a thought .. but as always car history and PPI come in to play.

Andy Kay

+1 these cars could be up to 33 years old. If the PO couldn't update the chain tensioners, what else couldn't he do? Can you remove the air filter cover to see if a pop-off was installed. These are the basics. There are too many good SC 's for sale on this site. Try searching with a heavy heart and empty soul by Pingman-he has two for sale.

whalebird

I'm on the fence with this one. I'm not sure it should be a deal breaker on a nice car. I would like to see the upgrade there, but a pristene original car could have easily missed the opportunity. It's all part of that slippery slope - especially with ulta low mile examples.

theiceman

By the way Andy i don't have a pop off valve ..
.. I have a pop off airbox instead ...

Peter Zimmermann

Yep. I know owners who resisted the change, and opted to replace original tensioners with original-type 930 tensioners, simply because they were concerned about maintaining their car's originality. It had nothing whatsoever to do with being cheap, or maintenance neglectful, it was owner choice. I had customers who drove perfectly maintained cars, and after a tensioner-related event, opted for the 930 units, along with new chain guides and cam o-rings, even though I presented them with the option of a Carrera Tensioner "upgrade."

Andy Kay

There's a lot more info needed before one can make a buying decision. A PPI is a must but I thought Plantman was looking for some general advise. He never said the cars were pristine or low mileage. IMHO, if a 33 year old car hasn't had the basic updates, then I would keep looking.

Ice-I called it a pop-off. Where did the valve come from?

Peter Zimmermann

"Pop-off" is normally referred to as a "pop-off valve."

Andy Kay

Peter/Iceman,
Funny you should mention that. Page 97 of 101 Projects For Your Porsche by Wayne Dempsey is Project 32-Pop-Off Valve Installation. I really don't care if you call it a pop off valve or pop off airbox. I was just trying to offer Plantman my $.02. I'm going for a drive before the temp hits 100! Enjoy your weekend.

aadrew10

I think 'pop off airbox' was meant as a joke.

whalebird

I always called it a "toilet lid".

rusnak

I knew a guy named Popov. That guy could sure hold his liquor.

Houpty GT

I have the pressure fed tensioners on my 1981 911. I would not have changed them if I were to do this again. My opinion on the topic is that if the original tensioners are working then do not change them. When they start to fail and make noise then go ahead and buy the pressure fed tensioners. Unlike the early tensioners the ones in the SC's do not appear to be less reliable then the pressure fed tensioners. I think this mod is pushed to heavily and not as necessry as people will try and make you feel.

Edgy01

The advice above is all sound. I felt that the oil supplied tensioners finally solved an age old problem. Why early 911 owners wouldn't upgrade to me was beyond me--it was not really expensive, and the alternative was -- well, bad. As Ice suggests, if the tensioners were not done, what else was skimped upon? Don't let it break the deal but if you buy one, do that yourself soon if it isn't in there.