Advancing a cam

[Mwilson]

I tried to advance my cam over the weekend, My crank gear has A2-A8, 0 and R2-R8. Well I set the crank gear on A4 and lost 15psi cranking compression? Im going to tear it apart tonite and was considering just going to A8 doing a compression check the R8 and doing a compression check. The original problem is I think I stuck a cam in thats a little too big. My original cam I thought was too small but looking back I think it was too far advanced. Original cam had the motor at 210psi and would only rev to 5,500 it was installed at 99* current cam has me at 175psi installed at 106* and it revs to my limiter which is 7,200 just kinda lacks on the bottom end so I wanted to get some bottom end back and bring the rpm range down to 6,500-6,800 or so. Any sugestion will be greatly appreciated.

As soon as I can afford it Im going to get heads and raise the compression from 11.29 to 11.75 or so which should make my cam happier.

[rookie]

Usually, not always, the cam is installed 4 degrees advanced, 6 at the most, if you are loosing pressure I don't know that I would go any more advanced.
Have you had the cam checked to make sure it is what they sold you?
If I remember it was a Comp and most of there off shelf cams are on a 110 separation could you refresh our memory with engine and cam specs.

[Mwilson]

Originally Posted by rookie

If I remember it was a Comp and most of there off shelf cams are on a 110 separation could you refresh our memory with engine and cam specs.

I think I did something wrong in the Advancing process, I went 2* but I messed up somewhere?

cam is comp 288TLS

259/266 @ 50
106 lsa
106 Icl
.555/.570

motor is 11.29:1 383

[Stan Weiss]

Originally Posted by Mwilson

I think I did something wrong in the Advancing process, I went 2* but I messed up somewhere?

cam is comp 288TLS

259/266 @ 50
106 lsa
106 Icl
.555/.570

motor is 11.29:1 383

When the cam is advanced you should always see an increase in cranking pressure. Do you just move a gear on a keyway or check with a degree wheel?

[john hennessy]

with that compression, be very careful adjusting the cam timing as valves will get very close to the head

[john hennessy]

sorry i meant to say very close to the head of the pisons,
the cat walked on my keyboard.

[Mwilson]

I really didnt want to degree it, Ive been running it striat up and just wanted to change the crank gear to another keyway, later when I do the head swap I will degree it again. I cant imagine im a tooth off but it runs horrible until it get up to 3,000 or so

[rookie]

You might want to degree it, it may already have 4degrees built in, or your gear may not be marked correct.

Your crank gear should have three different marks as well as three different teeth, mine has a 0, a ^ and a square mark to line up with the cam gear depending on straight up, adv. or retard, respectivly.

[Mwilson]

Update, I was a tooth off, before anyone gives me hell it was easy to do because of the way the marks line up, Now I have it on A8 and lined up A8=4* at the cam per the instructions with my timing set. Runs freakin awesome! Leaks oil again, so I dont think I'll make the track thursday unless I get a burst of energy tommorow and drop the oil pan again.

[Stan Weiss]

So what is your cranking pressure now?