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Discussion Starter · #1 ·
To the cam gurus. I know that there will be a need to measure valve clearance, but over all I want to know if a specked cam Dur @.050 238/252 625/625 115 lsa if that would work in an LQ9 .030 over.
TIA
 

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238/252 is quite a big exhaust split, which from what I've read is normally used on an LS3 style head (as the intake flows way better than the exhaust), so might be a better combination is avaialble for an LQ9 (depending on the heads). As an example, say a 240/244 whilst still on a 115 would have less overlap, so possibly easier to tune and more driveable (although that's a relative term when you're talking ~17* of overlap at 0.050"), but more intake duration so possibly more power / rpm potential...

In terms of PTV, from what I've read it's right around the 231+ intake duration where you really start to need to check PTV, so yeah, at 238 you'll be well in to not only having to check it, but quite likely having to do something about it...

Although depends on gasket and heads, as above, just assumed stock.
 

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not a cam guru, but this is my take:

Intake valve events lean a little toward the aggressive side for 5.7-6.2L LS naturally aspirated engines, but not overly so. pretty good for a max effort cam.

But, i don't see the point of running an exhaust side this aggressive and then only having 15 degrees of overlap. you're opening the exhaust valve sooner and letting pressure out, but closing it at the same time as a cam spec'd with a smaller exhaust side and a closer lsa. maybe good for higher rpm to negate pumping losses, but plenty of cams with smaller exhaust specs and similar overlap make really good power. yeah, i don't get it. close the spread and let the exhaust side do what it's meant for. on that note, if you do a quick google search, this is really similar to cam motion's "race day" cam but with much less overlap. the cam motion cam it has a lobe seperation of 108.5 and a 3.5 degree advance, giving you something on the order of 28 degrees overlap measured at .050" lift. Plenty of overlap for that "because racecar" naturally aspirated build. A streetsweeper cam is better if you want something closer to 15-16 degrees of overlap, in my opinion.

if you decide to stick with the cam, and you are naturally aspirated, you're probably going to want some domed pistons with reliefs to keep compression up and pretty nice flowing heads. i really don't think it matters if you use rectangle or cathedral port.
 

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Discussion Starter · #8 ·
238/252 is quite a big exhaust split, which from what I've read is normally used on an LS3 style head (as the intake flows way better than the exhaust), so might be a better combination is avaialble for an LQ9 (depending on the heads). As an example, say a 240/244 whilst still on a 115 would have less overlap, so possibly easier to tune and more driveable (although that's a relative term when you're talking ~17* of overlap at 0.050"), but more intake duration so possibly more power / rpm potential...

In terms of PTV, from what I've read it's right around the 231+ intake duration where you really start to need to check PTV, so yeah, at 238 you'll be well in to not only having to check it, but quite likely having to do something about it...

Although depends on gasket and heads, as above, just assumed stock.
I was actually thinking of throwing ported LS3 heads with a FAST 92 on top. I have everything to do it.
 

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Discussion Starter · #12 ·
Cart before the horse?

Based on the little bit of info you provided, that stick is about 10° too big everywhere.

Then again, WTF do I know?
No this is the combination that I'm going to do. I know that ultimately I have to measure everything. I also have in mind the GT11 cam. But definitely doing nitrous. I want to make sure I don't buy a cam before I'm sure that it will clear. Why I'm asking questions 🤘🏽👊🏽
 

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What NotHubert is trying to imply is that you probably can't get any better cam advice than from EDC - cams are his bread & butter..

It's like you coming here and posting for handheld shield advice, and then ignoring the input of Captain America. Talk to EDC.
 

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No one listens to me....

I don't have a You Tube channel or an Instagram account so what I do isn't credible. ;)

 

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Discussion Starter · #16 ·
What NotHubert is trying to imply is that you probably can't get any better cam advice than from EDC - cams are his bread & butter..

It's like you coming here and posting for handheld shield advice, and then ignoring the input of Captain America. Talk to EDC.
I guess me saying that I have some thinking to do and maybe going with a different cam wasn't good enough.
 

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Discussion Starter · #17 · (Edited)
No one listens to me....

I don't have a You Tube channel or an Instagram account so what I do isn't credible. ;)

I'm not dismissing you I replied that maybe I should go with a different cam like a GT11 and got no response other then a snarky remark. How about this:

"I see you're trying to get advice. The cam you're looking at won't work because a b c and d. Me I'd look at another cam. Maybe look at these cams a b or c would work better. What's your ultimate goal and that would help me help you out."

That would be better then talking down to someone. We are all grown men who pay our own bills some of us own businesses and don't talk down to people who don't know rather then take a moment to explain and educate some who are ignorant on the subject matter. I'm sure that you don't know anything about windshield installation but I would take time to educate you instead of talking down to or try to be funny at your expense. I've been doing windshields for 15 years and have had a business for 8. So if you're still wanting to come back at me save your energy and go somewhere else to be snarky and condicending. I'm asking to be educated.
Thank you 👍🏼
 

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I definitely misread your post then. It sounded as if you meant, "nah, i'm doing this, i just want to know if it clears." Re-reading it, i get what you meant now.

However, there are probably a lot of cams better suited than your two current choices.

As far as the sarcasm, it's not that serious, man. We've all been knocked around on these forums and learned a lot along the way.
 

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Discussion Starter · #19 ·
I definitely misread your post then. It sounded as if you meant, "nah, i'm doing this, i just want to know if it clears." Re-reading it, i get what you meant now.

However, there are probably a lot of cams better suited than your two current choices.

As far as the sarcasm, it's not that serious, man. We've all been knocked around on these forums and learned a lot along the way.
Thank you I'm open to other cams better suited. All I want is a streetlight to street light fighter. That was my fault in not specifying what I want out of a cam. I've had a high reving LS engine shifting at 6800 with a 7200 rpm red line. I'm looking for a cam that works between 1800-6500 rpms. Want to embarrass a few 392s. That's all....🤘🏽
 
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