[dt]

Is it a MUST to degree a cam?? I know guys that just install them dot to dot and thats it. What do you guys think?? Thanks.

 

[MrBill66Malibu]

I think if you care about the performance of the engine you are building then degreeing the cam is must do. I will say this, I always degree my cams. I only build an engine maybe once a year or less but, I have the equipment to do so. You could even borrow it from a friend or have them do it with you. Then when there is question of performance I can give accurate information. Plus you would be surprise how "off" things can be as far as manufactured parts. So the short answer is YES!!! lol

 

[64play]

Does every new car GM puts out need the cam degreed in them? Are cams one of the only parts in a motor that we can't trust the machining on? Always been curious as to what the factories do.

 

[Mike]

As most are referring to an aftermarket cam and/or timing set ,you can't compare it to what GM did.
Cam's have been known to be a couple degrees off spec and some timing sets can be way off spec.
Best to check just to be sure.

 

[MrBill66Malibu]

Does every new car GM puts out need the cam degreed in them? Are cams one of the only parts in a motor that we can't trust the machining on? Always been curious as to what the factories do.

Dan,

I would think that the factories manufacturing tolerances today are much better then they were 30 yrs ago.
I was really referring to most of the non factory high performance parts we usually install in our cars today. No, cams are not the only parts we can't trust. I installed a Eagle stroker crank in my 385, not only was the thrust bearing surface not polished correctly the hole where the pilot bushing was machined too large so we had to knurl the outside of the pilot bushing and locktite it in. My sons 5.0 crank had a similar problem with the pilot bushing area was not drilled deep enough, so we had to machine his bushing down to fit.
When building any engine today we check all measurements of all components, especially aftermarket stuff

 

[64play]

Thanks, Bill. That helps explain. Is a guy better off going with GMPP stuff than aftermarket?

 

[MrBill66Malibu]

Dan,
It really depends on what you want to build. Checking all measurements is just part of the process. There are very good aftermarket components it just a matter of making sure they all work together.

 

[trmnatr]

Is it a MUST to degree a cam?? I know guys that just install them dot to dot and thats it. What do you guys think?? Thanks.

IMO Yes!!!!!!!!!!!!!

I have installed many Crane Cams with timing sets when Crane made the gears but used German chains,,, They were ALWAYS on the money

I still had one when we did the Camaro's 400 small block, cam ground with 3° od advance, which put the ICL @ 102°, exactly where I wanted it, so I put it dot to dot and degree the cam, the ICL came in dead on at 102°

Now I have seen the same accurate ground cams with the same timing sets check good on GM cranks but not aftermarket cranks

Some cam cores are off now days on the key location and if they grind to make the key location correct, they grind through the heat treat, so the cam will be off when you degree it. I have seen this 1 given cam core 8° off, swapped in a core of my preference and it was dead on the money

Your really "rolling the dice" and hoping for a home run if you line them up dot to dot

I have seen many engines not perform until the cam was degree'd to find it was 4°+ off which caused lack of low end, have seen them too far advanced causing lack of top end power

Wish you the best if you choose not to but you can buy degree wheel kits cheap, I would suggest using the largest degree wheel you can afford

The Erson Pro Degree wheel is VERY NICE but this is not fit for one time a year use, This thing is durable for people who degree a bunch

 

[trmnatr]

Does every new car GM puts out need the cam degreed in them? Are cams one of the only parts in a motor that we can't trust the machining on? Always been curious as to what the factories do.

You can't trust the machining of anything, Read my post above and you will see the problem with 1 brand cam cores available, which is why some people prefer the other brand (Cam cores, not grinders like Crane, Erson, Comp etc)

You must check EVERYTHING when you build an engine

 

[427L88]

One thing you can do is check the cam using UDHarold's quick n dirty method. It tells you whether the cam is phased retarded, straight up, or advanced.

I tell you what, the machine shop put a cam in -7 instead of +7, and Harold Q-n-D method caught it. I only put a degree whell on AFTER I "degreed" the cam using a 6" dial caliper.

Watch the #1 valves as the engine runs up to # 6 firing position; you'll see the intake opening and the exhaust closing. Their relative postion at TDC gives the cam phasing; if the intake has passed the exhaust on the way down(open), then the cam is advanced ( most cams prefer this setting). If they stop and are equidistant from the deck, its "straight up", and if the intake does not pass the exhaust on the way down, its in retarded. I literally set the cam timing using a dial caliper and tweaking the offset bushing until the intake was .060" closer to the head deck at TDC. Put the wheel on, it checked perfectly for +7, peened in the bushing and bolted everything down.

Heck, it took me twice as long to get good repeatability with the degree wheel and dial indicator setup, than to degree the cam using the #6 TDC trick.

Your typical +4 setting is like .020-.030 closer to the deck, .050-.060" is really advanced. Man it ran well at that setting.

 

[dt]

Thanks everyone for the replies. I always felt it was necessary as well. You guys just confirmed it for me.