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EPS 230/234 Acting HUGE

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Old Oct 4, 2010 | 12:21 AM
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Default EPS 230/234 Acting HUGE

I just finished installing LS6 heads and intake, 0.040 MLS gaskets, an EPS 230/234 .600/.602 112+4, 42lb injectors, and supporting mods, and the cam is acting like it's a gigantic cam in terms of idling. It's wanting to pull in between 11 and 12 grams of air at idle.

Is it normal for cams with EPS lobes to act like they're bigger than they are?
Old Oct 4, 2010 | 12:26 AM
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I didnt see you mention anything about tuning. What kind of intake are you running? do you have a vac leak somewhere? What is it idling at?
Old Oct 4, 2010 | 12:36 AM
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Originally Posted by jimbo98z
I just finished installing LS6 heads and intake, 0.040 MLS gaskets, an EPS 230/234 .600/.602 112+4, 42lb injectors, and supporting mods, and the cam is acting like it's a gigantic cam in terms of idling. It's wanting to pull in between 11 and 12 grams of air at idle.

Is it normal for cams with EPS lobes to act like they're bigger than they are?
seems pretty normal with any cam in the 230 range....and 8* of overlap at 0.050
idles around 60~65 kpa?
Old Oct 4, 2010 | 12:39 AM
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Running an LS6 intake, factory ported throttle body with the hole drilled to 0.2100". The car had a base tune put on it with EFI Live, and will be getting a full tune this week, but the car is struggling to maintain a 1000 rpm idle on starting. Once it runs for a while, it will come down and idle from 980-1050. It's just got a hell of a lot of chop to it.

I'm not really complaining, and it will be fixed this week, I was mainly looking for if anybody had any input on whether the EPS lobes make a cam act like it's a bigger duration cam than if it had something like an XFI lobe
Old Oct 4, 2010 | 12:42 AM
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Originally Posted by soundengineer
seems pretty normal with any cam in the 230 range....and 8* of overlap at 0.050
idles around 60~65 kpa?
Yea, something in that range, maybe a little lower, towards ~57, I don't remember right off. More out of curiosity than anything. I keep forgetting about how little overlap it actually has though. I'm sure everything is normal, we spent a solid 15-20 minutes looking and listening for vaccuum leaks after the first start.

It sounds like a friggin beast though
Old Oct 4, 2010 | 12:44 AM
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I had a lot bigger EPS cam in my 346 than yours has....
I idled at 75kpa....
its normal...
welcome to lopety-lope
Old Oct 4, 2010 | 12:51 AM
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8° should have a fair amount of lope. I ran a 15° and it was really choppy and a 4° and it was a lot more tame, but still chopped.
Old Oct 4, 2010 | 01:08 AM
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Get a tune
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Old Oct 4, 2010 | 11:56 AM
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Originally Posted by 01ssreda4
Get a tune
It's going to RPM next week
Old Oct 4, 2010 | 12:26 PM
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Originally Posted by jimbo98z
It's going to RPM next week
Did PatrickG spec that cam? Any milling done to your heads?
Old Oct 4, 2010 | 12:30 PM
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Post up a video.
Old Oct 4, 2010 | 06:07 PM
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PatrickG did spec the cam.

No idle video yet, because when I went to crank it, it broke one of my rocker arms and took a spring with it. I'm thinking maybe the ramp rate and lift is too much for stock rockers...
Old Oct 4, 2010 | 06:42 PM
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Really? Thats interesting. First I have heard of a stock rocker breaking.
Old Oct 4, 2010 | 06:45 PM
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Originally Posted by 01ssreda4
Really? Thats interesting. First I have heard of a stock rocker breaking.
Yup. The last ~1/2" on the valve end just broke right off. There's no bind in the springs, so I'm thinking just random parts failure.
Old Oct 4, 2010 | 06:55 PM
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Your heads milled?
Old Oct 4, 2010 | 07:31 PM
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Originally Posted by masterz28
Your heads milled?
Nope, but I figured out the problem. The valve seats that were sent with the springs were stock style seats, so the inner spring is binding. Just need to take the rockers and springs off and install my new seats when they get here
Old Oct 4, 2010 | 07:34 PM
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Originally Posted by jimbo98z
PatrickG did spec the cam.

No idle video yet, because when I went to crank it, it broke one of my rocker arms and took a spring with it. I'm thinking maybe the ramp rate and lift is too much for stock rockers...
Sounds like an install error. I have a lot more lift with pretty aggressive lobes and still run the original stock rockers with no problems so far.
Old Oct 4, 2010 | 07:42 PM
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Originally Posted by DrkPhx
Sounds like an install error. I have a lot more lift with pretty aggressive lobes and still run the original stock rockers with no problems so far.
Read above post. The wrong style seats were sent with the springs, and it's been verified with PRC. They're overnighting me the right ones.
Old Oct 5, 2010 | 12:58 PM
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if it broke a rocker I wonder about the PR and lifters.
Old Oct 13, 2010 | 10:35 AM
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Originally Posted by Matt@Texas-Speed
I've seen quite a few of the cam sheets PatrickG has sent to various people, and I assure you, the lobe numbers listed as "EPS" are really LSG lobes. We have verified it with several Comp employees as well! Like Jason said, Comp made them, and they are available to ANY of Comp's retailers on custom grinds.

I could post screen shots of the cam recommendation sheets and just edit out the customer info for yall to see, if that helps

Whatever Comp employee you have verified it with needs to double check their information. What do you think the 'G' in LSG stands for? They are my lobes and are supposed to be proprietary to me. If Comp is selling these lobes out the back door they are violating the terms of the agreement we had...



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