LilJayV10

iTrader: (39)

I am going to degree the cam in my LS1 when I put it in.

When I bought the degree kit it came with a video that shows how to do it. The video is OK but there are a lot of things I don't understand.

First being using a TDC stop. It says to use a stop, then turn the motor till the piston hits it and zero the degree wheel out. Then to go backwards till it hits again. Then split the different and thats true TDC.

How does that find true TDC? I don't understand the math I guess.

I had a question about finding the intake center line but I watched the video again and it made a little more sense.

I am going to use light weight checker springs to check PTV clearance. The way the clay method was shown did not seem accurate.

Any tips or advice would be great.

Thanks.

joecar

As the crank passes thru TDC, the piston appears motionless at the top from a few degrees BTDC thru to a few degrees ATDC... i.e. dial indicator can't detect any piston motion as the crank sweeps those few degrees...

The stop method locates the piston at the same location BTDC and ATDC, so the middle between those two positions is the crank's true TDC.

vettenuts

iTrader: (4)

Are you doing this with the heads on or off? Double check your piston TDC when to set the wheel as this can cause larger errors once trying to find the intake center line. Use a long wrench to turn the crankshaft and only turn one direction when finding the intake center line. Once you find the intake center line, double check the cam with the opening and closing points.

Its been a while since I did this, but it is a great learning experience.

LilJayV10

iTrader: (39)

I tried to tackle this after I got off at work tonight. Geez comp cams, some pictures would have been nice. It took me about ten minutes to figure it out so it wasn't that bad.

The hardest part was setting up the dial indicator for the lifter. The heads are off it now, as I am putting different ones on. I tried it a few times but my numbers were off. I got 111 intake center line once. I noticed the wheel had come loose so I started all over again. I did it three more times and got 112.5. It's suppose to be at 110. I don't know if its me, probably is, or I need to retard the cam some.

On the DVD that came with it kit it said when advancing the cam that the fat side of the bushing should be towards the outside of the cam gear. What about retarding it? They didn't mention that.

Also does the intake valve start to open right before TDC? I set the dial indicator on the intake valve with the exhaust valve all the way open. When turning the motor at TDC to check lift at about 10 degrees before TDC there is about .050 lift. Is that right?

Once I figure out how to put these bushings in I will be able to see if it changes anything which will help tell me if I am doing this right. After I did it a few times it made sense. Without anyone that knows what they are doing watching me I am worried I might be doing it wrong.

Thanks.

vettenuts

iTrader: (4)

What are the specs on the cam, can you post a photo of the cam card? Depending on the cam, the intake will start to open before the piston is at TDC. If the heads are off, there is another method of finding TDC of the piston without the stop.

Shoot me a PM with your e-mail address. I can send you what I wrote up for myself to use as a procedure when I did mine. It is somewhat specific to my motor but it may help you out.

LilJayV10

iTrader: (39)

I don't have the card in front me right now. I talked to Geoff at EPS today, that's where I got the cam from. He said it's not uncommon to have some TDC overlap. He explained the whole process to me. It's the same as the comp cams video said to do it.

One thing he did mention was that the cam lobe is asymetrical(sp?)and that I should also check the base circle of the cam at .006

It seems the way I am doing it is right. I will double check it again tonight and see what the numbers are.

vettenuts I will shoot you a PM here in a bit. Thanks for the help.