COMP Says XFI 465 TDC Method Won't Work!
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Joined: May 2004
Posts: 576
From: Missouri
COMP Says XFI 465 TDC Method Won't Work!
COMP Says XFI 465 TDC Method Won't Work!
I have to pull the manifold again due to a new Comp Lifter with a stuck plunger.
When I set the Valves I used the TDC Compression stroke system following the firing order and setting both valves lash on the cylinder.
Comp says with the XFI 465 cam and I guess all of their XFI cams the TDC system won't work.
Since I get to check or repeat all of the valve adjustments with manifold back off, I would be willing to try another method. But I don't see why this cam is all that much different than any other. No cam should have the intake and exhaust open at TDC on the compression stroke.
Am I wrong? Is the TDC system useless with this cam?
Camshaft 07-465-8 260XFI HR13
Duration 210 , 218
Lift 0.56, 0.555
LSA 113
The only problems I saw with the car was a loud tapping on the passenger side of the engine. Turned out the stuck lifer plunger was turning it into a loose solid lifter. Engine is down on power, but I think it is a sensor / program / Opti problem.
I used a piston stop to find TDC, balancer is marked in 90 degree quadrants and I know about the two TDC positions on each cylinder. I also set the arrow on the hub to vertical when I installed the hub with the dot to dot method used to set the timing chain set.
Comp wants me to use the intake / exhaust movements to set the valves. They say the overlap will prevent the TDC method from working.
Thoughts?
Thanks
Alan
I have to pull the manifold again due to a new Comp Lifter with a stuck plunger.
When I set the Valves I used the TDC Compression stroke system following the firing order and setting both valves lash on the cylinder.
Comp says with the XFI 465 cam and I guess all of their XFI cams the TDC system won't work.
Since I get to check or repeat all of the valve adjustments with manifold back off, I would be willing to try another method. But I don't see why this cam is all that much different than any other. No cam should have the intake and exhaust open at TDC on the compression stroke.
Am I wrong? Is the TDC system useless with this cam?
Camshaft 07-465-8 260XFI HR13
Duration 210 , 218
Lift 0.56, 0.555
LSA 113
The only problems I saw with the car was a loud tapping on the passenger side of the engine. Turned out the stuck lifer plunger was turning it into a loose solid lifter. Engine is down on power, but I think it is a sensor / program / Opti problem.
I used a piston stop to find TDC, balancer is marked in 90 degree quadrants and I know about the two TDC positions on each cylinder. I also set the arrow on the hub to vertical when I installed the hub with the dot to dot method used to set the timing chain set.
Comp wants me to use the intake / exhaust movements to set the valves. They say the overlap will prevent the TDC method from working.
Thoughts?
Thanks
Alan
Registered User
Joined: Jan 2003
Posts: 90
From: The Assembly Room
Re: COMP Says XFI 465 TDC Method Won't Work!
Set the intake when the exhaust just begins to open, and the exhaust when the intake is just finished closing. This will assure that you are nowhere near overlap.
Registered User
Joined: Dec 1969
Posts: 27,730
From: Little Rock, AR
Re: COMP Says XFI 465 TDC Method Won't Work!
Regardless of whether what you tried works or not, post #2 (same as method #3 on my website) will work and is more often used on aggressive cams.
Originally Posted by shbox.com
Method 3
Another cylinder by cylinder method that does not require looking at the balancer position, follows:
(A remote starter switch is quite helpful)
Turn the engine in the normal direction of rotation until the exhaust lifter for the cylinder you are adjusting starts to move up (valve begins to open).
On the intake rocker arm, adjust for zero lash and add your desired preload.
Turn the engine over again until the intake lifter on the same cylinder comes all the way up (valve open) and then goes almost all the way back down (valve almost closed) .
Now, adjust the rocker arm for the exhaust valve on that cylinder to zero lash and add your desired preload.
Continue the above procedure for each cylinder until all valves are adjusted to the same amount of preload. This procedure will work for any hydraulic lifter cam with adjustable rocker arms. Refer to this diagram posted above if you need visual reference. The reason I specify lifter movement in the above is because when you start off with completely loose rockers, there is no valve movement to watch.
Another cylinder by cylinder method that does not require looking at the balancer position, follows:
(A remote starter switch is quite helpful)
Turn the engine in the normal direction of rotation until the exhaust lifter for the cylinder you are adjusting starts to move up (valve begins to open).
On the intake rocker arm, adjust for zero lash and add your desired preload.
Turn the engine over again until the intake lifter on the same cylinder comes all the way up (valve open) and then goes almost all the way back down (valve almost closed) .
Now, adjust the rocker arm for the exhaust valve on that cylinder to zero lash and add your desired preload.
Continue the above procedure for each cylinder until all valves are adjusted to the same amount of preload. This procedure will work for any hydraulic lifter cam with adjustable rocker arms. Refer to this diagram posted above if you need visual reference. The reason I specify lifter movement in the above is because when you start off with completely loose rockers, there is no valve movement to watch.
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