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Comp QXI Lobes

General engine tech -- Drag Racing to Circle Track

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digger
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Re: Comp QXI Lobes

Post by digger » Tue Sep 03, 2019 8:38 pm

CamKing wrote:
Tue Sep 03, 2019 2:36 pm
novadude wrote:
Tue Sep 03, 2019 2:12 pm
Wonder why they don't just play games with the advertised numbers instead of sticking to the industry standard of 0.006" for adv duration? Since everyone that reads the magazines wants short advertised duration for a given 0.050" duration, why not just design lobes that work and published advertised numbers measured at 0.009" or something? I think Isky does something like this.
Because if someone has it measured, and it's not what Comp said it is, it's Comp's fault. If it matches the specs, and beats the hell out of the valvetrain,
Maybe it's the lifters? Maybe it's the rockers? Maybe it's the pushrods? Maybe it's the lifter bores? maybe it's the lifter bore clearances? Maybe it's the oil? Maybe it's the valves? maybe it's the valve seat? Maybe the engine builder should have known it was to aggressive for his application?
It's called "Plausible Deniability"
Depends, is there a commercial available valvetrain setup that would live as expected ? What are the recommendations made for component selection for the lobes ?

Tom Walker
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Re: Comp QXI Lobes

Post by Tom Walker » Tue Sep 03, 2019 9:01 pm

The engine in the video clip sounds just like a diesel😳

406shark
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Re: Comp QXI Lobes

Post by 406shark » Tue Sep 03, 2019 10:40 pm

Tom Walker wrote:
Tue Sep 03, 2019 9:01 pm
The engine in the video clip sounds just like a diesel😳
That's what I was thinking when I listened to it.

Can you imagine if that small block Mopar had sheet metal valve covers instead of those thick cast aluminum ones? I don't think I've ever heard even a solid lifter setup sound that loud.



Jeff

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Re: Comp QXI Lobes

Post by n2xlr8n » Wed Sep 04, 2019 5:54 am

CamKing wrote:
Tue Sep 03, 2019 1:09 pm
Orr89rocz wrote:
Tue Sep 03, 2019 12:46 pm
CamKing wrote:
Mon Sep 02, 2019 10:49 am

No.
The force that is hammering the valve open, and slamming it closed, is the issue.
Mike answered it with this. Its not the lifter its the valve hammering the seat. Correct me if im wrong
Correct. The plunger is getting hammer also, but that's not what you hear. The issue is the valve hitting the seat, and the rocker hitting the valve tip.
Now, when the plunger is getting hammered, and collapsing, it can actually increase the velocity/acceleration rate at which the valve is leaving and hitting the seat.
Thanks for the clarification, fellas.
He who is in me is greater than he who is in the world.

Elroy
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Re: Comp QXI Lobes

Post by Elroy » Wed Sep 04, 2019 10:51 am

The fast Comp hydraulic roller lobes will make some power if you can keep them happy////and don't mind the noise///or just put solid roller lifters o them :lol:

paulzig
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Re: Comp QXI Lobes

Post by paulzig » Thu Sep 05, 2019 12:52 am

Tom Walker wrote:
Tue Sep 03, 2019 9:01 pm
The engine in the video clip sounds just like a diesel😳
It'll have some low down TQ then :D

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