350 Cam Swap

[Carl81]

I was just looking at the broken cam in my Honda. (Who would have thought you could drive any car at highway speeds with only 90% of a cam still attached?) Changing it just doesn't look too tough. What am I missing?

Of course the next question is: How hard is it to change the cam in my "81 Vette. Nothing is computer controlled anymore and I would like just a mild bump up to start. Is this anything a weekend hobby mechanic should even think about? Also keeping along the lines of a small bump, would the OEM parts hang in there or is a new top side be a mandatory part of doing any of this type of work?

As always, Thanks!




http://www.mycarframes.com

[Melsy]

I had an '81 and kept all the computer stuff (as archaic as it was back then). Changing the cam on that engine is standard small block Chevy stuff. You might want to try a blueprinted regrind of the L82 cam. Really wakes up the engine and is very streetable and stable and you won't have to mess with any top end work. This was also the famed 327/350 HP grind of the 60's. I think Crane Cams and others have blueprinted, and updated versions of this cam. Give them a call.

[Carl81]

Thanks. I will contact them. I am just looking for a good starting place and I like your idea. I know the hunt for power is the never ending story, so I will just consider this another chapter in getting there faster.

Have a good week.



http://www.mycarframes.com

[Nytro]

Changing the cam isn't hard at all if you are mechanically inclined, doing it right is a different story. Hardly any special tools needed, harmonic balancer puller and a special nut to put on the end of the crank so you can turn the motor with a ratchet are probably about it if you want to just do a cam swap and aren't fussy about getting maximum performance out of the cam. You have to remove the distributer, valve covers, rockers, lifters, pushrods, intake, front cover, balancer timing chain and gears then the cam. (Make sure you line up the timing marks properly before removing the timing gears and chain.) Installing it and degreeing the cam is absolutely the right way to do a cam swap. Crane offers a complete kit to degree a cam, part number 99030-1, it includes everything necessery to degree the cam. The benefits are complete accuracy with synchronizing the cam and crank together for maximun performance. Every credible engine builder will tell you this is as important as picking out the right cam.

If it were my engine and I was going to do a cam swap I would also replace the timing gears and chain, cam and lifters (lifters will come with the cam), pushrods and rockers and naturally the various gaskets.

Here is a great link explaining and talking about degreeing a cam.

http://www.forarforeningen.com/reports2002/degcam.htm

Lastly choosing a cam can be confusing. Whether your car is a stick or automatic makes a major difference, gear ratio, a different cam will affect your mileage and too large of a cam will have a negative effect on your engine vacumn, so I guess basically you dont want to go too wild. You need to talk to a cam expert and ask these questions and tell him what your objectives are. My 66 is a stick with 4:11's and no power steering or brakes. I am running an Edelbrock Performer RPM that has 292 duration with 488 lift. I am running 10 degrees initial with 27 degrees at the crank for a total at 1700 RPM of 37 total degrees of timing. I have no ping and I am able to run regular gas. One more thing to keep in mind is that a cam swap is probably going to give you worse gas milage, too much timing will cause you to have to run Premium so you don't want to run a lot of initial.

Hope this info helps you.