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Discussion Starter #1
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 to make sure Im going in the right direction. 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 make power to 5,500 on the dyno 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 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.
 

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Doing the 2 tests you are talking about will tell you if you are advancing or retarding the cam but problem is you still do not know where it is. Just because the gear is stamped "0" doesn't mean thats where your cam is in according to your cam card. Do you have or know anyone that has a degree wheel and dial indicator?
The other thing is, did you do the compresion test the say way both time? If you did one with the motor hot and the other with the motor cold the number might change.
Lastly advancing the cam will give you more bottom end but if you are looking to drop the range 500+ RPM's I would consider a different cam.
 

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Discussion Starter #3
I did both tests cold, Since I ran the cam at 0 and was kinda happy I was just looking to get a little bottom end back, I was told I shoulda installed it at 103 but I nstalled it strait up. So then I was told I could pick up if I installed it at 103. I just want to advance it some and go try at the track. I do have degree wheel and dial indicator. Do I just set the motor at TDC with a pointer at 0 on the wheel then set the dial indicator on my rocker arm and rotate it until the valve opens? My card says 38* BTDC open 70* ABDC close @ .020
 

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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.
 

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Why even bother owning a degree wheel or dial indicator if you are not using them.

Man' the way you are degreeing your cam is like playing Russian Roulette!

Not one timing set mfg has accurate degree changing grooves in their gears. Not one. By every word in your posts you have no clue where the cam is degreed in as far as Intake Centerline or valve events. Straight up is not ever straight up.

Circle track old school guys use cranking compression to decide where cam sets in. They also like big cranking compressions.

Those measurements are good long enough to get the engine started and then everything changes.

If you have to altar your recommended from cam company cam Intake Centerline by more than 5 degrees advanced or retarded, you have the wrong cam.

I guess you know that by changing the cam degrees like you are that you are at the same time radically changing your valve to piston clearances?

Ed
 

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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.
Did you happend to do a compression test just to see what it increased by?
 

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Discussion Starter #9
Did you happend to do a compression test just to see what it increased by?


yeah I did that before I even put the timing cover on! I was 175 then I messed it up and went to 160 now Im at 180 all done cold. Im gonna boost compression with new heads soon but I think its a better starting point, Im hoping to track test thursday but I need to drop the oil pan tommorow and fix a leak if im gonna do it.
 

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yeah I did that before I even put the timing cover on! I was 175 then I messed it up and went to 160 now Im at 180 all done cold. Im gonna boost compression with new heads soon but I think its a better starting point, Im hoping to track test thursday but I need to drop the oil pan tommorow and fix a leak if im gonna do it.
Do yourself a favor and use the gray RTV. It gets harder and to me seals better. I hate oil pan leaks,, wait I hate leaks period!
 
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