Please help me verify my valvetrain geometry
#1
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Once and for all, I'm trying to ascertain whether or not the #'s are off or where they need to be.
there are extra #'s, that make it harder, but I know some of you guys are smart enough to do this in your heads, which is why I'm looking to you--
I am as incompetant at math as I am to the art of applying lipstick...
Here's the scenario:
-----
(BC on cam unknown, but the cam is a Speed Demon Motorsports 226/.591/112, if that helps)
LS1 5.7 heads milled .040
Cometic .078 gaskets (vs .055 stock)
valves recessed .030
rockers shimmed .030
using 7.400 PR's
----
Is the PR length correct for these #'s?
How about estimated preload on the lifters?
Should I change anything to optimize geometry?
I have a friend who's saying that I'm losing a lot of power due to improper geometry, but I want to hear what you think!
I'm desperate to figure these #'s out the right way <img border="0" alt="[judgement]" title="" src="graemlins/gr_judge.gif" />
there are extra #'s, that make it harder, but I know some of you guys are smart enough to do this in your heads, which is why I'm looking to you--
I am as incompetant at math as I am to the art of applying lipstick...
Here's the scenario:
-----
(BC on cam unknown, but the cam is a Speed Demon Motorsports 226/.591/112, if that helps)
LS1 5.7 heads milled .040
Cometic .078 gaskets (vs .055 stock)
valves recessed .030
rockers shimmed .030
using 7.400 PR's
----
Is the PR length correct for these #'s?
How about estimated preload on the lifters?
Should I change anything to optimize geometry?
I have a friend who's saying that I'm losing a lot of power due to improper geometry, but I want to hear what you think!
I'm desperate to figure these #'s out the right way <img border="0" alt="[judgement]" title="" src="graemlins/gr_judge.gif" />
#2
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Well if your valve is closed roker arm should be centered (the tip of the roker) with the valve. what type of lifters are you using. and check your pre-load. comp r lifter i use go about 1/4-1/2 turn on 22lbs.
harry
harry
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Launching!
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If I had the tools and ability to check preload myself, I wouldn't have to ask these questions <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" /> <img border="0" title="" alt="[Razz]" src="gr_tounge.gif" />
The lifters are stock, by the way, and the car does run fine--at least to the point that I'm sure all the valves are closing...(I've got 800 miles on this setup), but the valvetrain is very loud---sewing-machine-like. <img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" />
<small>[ August 27, 2002, 03:35 PM: Message edited by: MDL-01C5 ]</small>
The lifters are stock, by the way, and the car does run fine--at least to the point that I'm sure all the valves are closing...(I've got 800 miles on this setup), but the valvetrain is very loud---sewing-machine-like. <img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" />
<small>[ August 27, 2002, 03:35 PM: Message edited by: MDL-01C5 ]</small>
#4
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The only sure fire way to check this is to mark the tip of a valve with a black marker, bolt the rocker back down and rotate the engine over by hand a few times. The wear pattern should be centered on the valve tip.
Shane
Shane
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OK thanks...--I'll give that a shot tomorrow...
What do you all think about the power-robbing aspect that my friend is claiming?
(BTW--it's not 2-3 HP he says I'm losing, but like 20+...from pushrods)
Is there any validity to that claim?
What do you all think about the power-robbing aspect that my friend is claiming?
(BTW--it's not 2-3 HP he says I'm losing, but like 20+...from pushrods)
Is there any validity to that claim?