I have 130,000 miles. Will a ZZ4 or ZZ9 cam mess up my engine? I've been told there are too many miles on my GTA to do a cam swap, because of all the power I will get. What do you guys think? Thanks.

 

I knew a guy that did a cam swap on an L69 with over 140k on the clock. Engine never blew up until he decided to do a cheap bearing and ring swap putting it into a different car.

But no, thats an old wives tale, engines will not necessarily blow up just because you suddenly have a little more power and some miles on it. Unless the engine was already on it's way out and the new abuse does push it over the edge., but then it was just a short matter of time anyway. It's not like a cam is a 150 shot or something.

 

You could look at it like this: too many miles for new parts?

What happens to the Corvette people at 130,000 miles, or others with higher factory output? Do they have too much power for their mileage?

Actually you have a very common concern, but I don't believe higher output automatically means higher wear. Especially on a street driven vehicle. This basically means the majority of driving will be normal off-idle to mid-rpm driving, not all out constant WOT racing.

 

As long as the engine isn't burning oil, holds good cold and warm oil pressure, and is in a general good state of tune, there's nothing holding you back from a cam swap. It gives you a good chance to see just how worn many of the other parts are as well when you're in there. Just don't pick the Summit Racing 1104 cam for a 305 TPI... Yowza, did I get burned for that one. LOL!

 

I did a cam swap with about 168,000 miles on my engine; it now has nearly 240,000 with no problems, other than taking some oil.

Pete