roller cam in my 75 roadster

[Jim T.]

Re: roller cam in my 75 roadster

Ross, my 1968 L79 has 97,421 miles on it now. It will be 46 years old this month. The engine still has it's original pistons, rings, valves, camshaft and lifters. The engine has not been apart for engine work. New clutch pressure plate about 41 years ago. Runs very good, still really enjoy the acceleration in first, second, and third gear. Your 1975 has low miles if the odometer has the correct mileage, my 1970 had 160,000 miles on it when I removed the engine to install a GM higher horsepower crate engine in 1992. My 70's 350/300 engine was running fine when it was removed, I still have it and would reinstall it if I had to. I agree with the posters who do not recommend a rebuild for your 1975's engine. I use the 10W40 diesel type oil in my cars for the ZDDP protection that no longer comes in other automotive oils to protect the flat tappet cam and lifter cars. The oil in my cars engines stays really clean looking a lot longer in using the no-lead gasoline.

Interested in what others have to say about helping clean a dirty engine. A long time ago a person told me he was using one quart of transmission fluid at the oil change and changing the oil again when it showed dirty oil.

[Ed D.]

Re: roller cam in my 75 roadster

Make sure you check the cam lobes. Many mid 70's corvettes had problems with wiped out cam lobes. My 74 with only 36,000 miles had several lobes that were perfectly round. This was 22 years ago and cant remember how many of the lobes were bad.
Ed

[Bill L.]

Re: roller cam in my 75 roadster

Ross,

My 70 L46 has 111k miles and runs extremely well with no oil consumption, smoke, or tapping.

Bill

[Rich C.]

Re: roller cam in my 75 roadster

From having the unpleasant experience of having a flat tappet cam lobe disintegrate spraying its filings onto pistons skirts and the ensuing horror show... the roller cam seems so much safer. Much less friction. I'm sure I'll get berated for this view... I know flat cams were used for 80 years, but roller cams and rockers ARE an advance.

[Joe L.]

Re: roller cam in my 75 roadster

From having the unpleasant experience of having a flat tappet cam lobe disintegrate spraying its filings onto pistons skirts and the ensuing horror show... the roller cam seems so much safer. Much less friction. I'm sure I'll get berated for this view... I know flat cams were used for 80 years, but roller cams and rockers ARE an advance.

Rich------


There can be such problems with roller cams, too. The main one is the roller bearings coming apart. However, these are extremely rare if the cam is properly installed and high quality parts are used (i.e. not some "el cheapo", off-brand hydraulic roller kit).

Nevertheless, I greatly favor hydraulic roller cams. As I mentioned, I consider that these make flat tappet cams completely obsolete. For the purposes of "originality" I suppose flat tappet is the way to go but for the purposes of functionality and durability, I like hydraulic roller.

In fact, when hydraulic roller cams were first used in PRODUCTION (1987 for Corvettes), I couldn't wait to install one in my small block. However, the GM set-ups could not be installed in pre-1987 blocks for several reasons. So, I had to await the aftermarket to come up with a RETROFIT set-up. As it turned out, this was more difficult than it might seem. I called all the major cam manufacturers and kept after the ones that were actually working on getting such a product out. These were Crane, Crower, and Federal-Mogul/Speed-Pro. Federal Mogul/Speed-Pro was the first one to get the product on the market and I bought one immediately.