Hi Guys,
I've been away from engine building for several years….things are foggy yet coming back slowly.
I've got a '67 E block that I had rebuilt years ago…never assembled the pieces….I now have the crank and two pistons in- trying to degree the cam to make sure I have everything dialed in.
This is a very stock motor- bored out to accommodate 350 standard bore pistons, Crane Cam (mild) 804542 (part number). I'm pretty sure I'm running a cloys timing gear set - it's marked as MP409.
I followed the Mondello book on degreeing cams (I think this is a reputable source). I followed the directions and checked my work three times.
Crane specs say that my intake duration should be 216 and exhaust 228 (at .050). I'm off with my actual readings …..I'm getting 222 intake and 226 exhaust. I believe that makes my intake 6 degrees advanced and my exhaust 2 degrees retarded.
Does it sound like I'm doing something totally wrong? I was guessing that my intake and exhaust should be off by the same amount ??
Any ideas, guidance, etc would be appreciated.
If need be I can redo my approach and follow different directions….
Motor will be very mildly street driven…definitely not a racer.
Thanks very much. This motor is going into my '68 442 Convertible.

 

It's doesn't mean anything is retarded or advanced, just that the cam may be incorrect.
Double check your at .050 numbers after you've verified tdc.
I had that cam in a 350, it was a little lazy.

 

Use the lobe centerline method as see where you are at. Look at the camshaft card .

 

You can also find clear, concise directions for degreeing your cam in the catalog on compcams.com

 

Based on your pic, are you trying to find tdc with a dial indicator? The positive stop method is more accurate.

 

As above, use the stop method. You can bolt a head on with a couple bolts and use a stop that goes in a spark plug hole, or run a thick strap across the top of the cylinder, with a plate under it or a bolt through it to contact the piston. It is almost not worth degreeing the cam by guessing at TDC with a dial indicator on the piston, because there are several degrees of turning where the piston hasn't moved from TDC.

 

Thank you! I read that dial indicator was best ….. I'll do the stop method. Thanks for setting me straight.

 

What part of San Jose are you?

Gene

 

Ok- now I'm way over my head.
I took the new advice and did the piston stop method of determining TDC….this showed my TDC was off by a degree.
Now I'm getting really weird readings. I called Crane Cams to see if my cam card was wrong….he recommended decreeing my cam dry, no oil on lifter or cam and to put pressure on the lifter extension. Does this sound right?
My lifter extension is an old .921 lifter with a bolt shoved into it- I"m beginning to think this is not the most accurate way to do this.
What do you guys use to get dial indicator readings off your lifter?
Again- sorry for bone head questions- I want to dial this thing in and definitely want to do it the right way. Any ideas, direction would be appreciated.
Thanks

 

I use the intake center line way. After I get what I want I check duration as per cam card.
Where in San Jose ?
Gene

 

Yes, cam lobe and lifter bottom should be dry. The method you are using should work fine, but maybe set your dial indicator up so it touches the lifter rim. You are trying to find out what the reading is at .050 before TDC and after TDC. Add those 2 numbers together, divide by 2 and that is the lobe centerline. Hopefully that will match the Center Line on your Cam Card.

 

Hi Gene,
you and I have talked a few times over the years- you've always been very helpful. I live in Campbell near Pruneyard.
I'm finding that it's really hard to dust off my brain cells and get back up to speed on all the details of building an engine the right way. I'm getting close to throwing my hands up and letting an expert take over. I've got a clean 400, all machined, all the parts are here. It might be good for us to talk- If I get any more pressed for time I will need someone to take what I have, check everything, put it together and fire it up to make sure everything is all good before I drop into my car. Is that something you're up for? If so pm me your contact info. Thanks Mike