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Discussion Starter #1
Looking for a picture of a PI cam next to a NPI cam. I can't even find a decent picture of NPI cams by themselves. WTH?

I am wondering if there is a real difference that you can visibly see in the lift of each cam if you were to hold them side by side. I'm assuming there is but its been bugging me.

Thanks

Edit: I know you can see there is a difference in the duration of each cam
 

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I don't think you can eyeball it and see the difference, unless of course you are looking at the engineering/part number :)
 

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Discussion Starter #5
Ok thanks for the quick replys guys. Helping a friend out with his PI cam swap.

One other question; I have been told there is always an FYC something something part number on the NPI cams right? and a YC6 something something part number on the PI cams right? He might have bought the wrong cams..
 

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I just checked my 01 Romeos and my 00 windsors

Windsor: XL3E-6C255-A6C (LH), XL3E-6251-A6C (RH)
Romeo: 1L2E-6A27-CA (LH), 1L2E-6250-DA, (RH)

Npi part numbers should start with an F suffix like F1, F4, F6, F8 ect. There might not even be that many part numbers on the npi cams, I believe they were the same from 94-early 01
 

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My Romeo PI cams have those same exact part numbers.
 

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The difference would be most noticeable on the exhaust lobes @ 0.036".
that is right at a millimeter, that MIGHT be noticeable, or at least measurable.

Are these press on or bolt on gear cams? The washer and bolts are different between PI and nPI for the bolt on ones.
 

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The easiest way to tell is get a micrometer and measure the lobe at max lift, and the base circle. Subtract the base circle measurement from the larger measurement, and that gives you lobe lift, which you can then look up the lift measurements for a PI cam and for an NPI cam, and determine what you have.
 

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Discussion Starter #11
Ok thanks guys. We pulled the the cams out of his mustang and they look like a NPI cam with larger duration then the PI cam but the lift looks the same and there is no part number on them.. Are there cases where the cam might not have a part number at all?

we might have to go get a micrometer...
 

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stock cams out of his mustang? Does it have tulip shaped intake ports or circle shaped intake ports? If you for whatever reason didn't remove the intake manifold and he hasn't put a PI intake on his NPI motor then you could look at which direction the first intake runner goes. Or buy and measure with a good micrometer.
 

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Discussion Starter #13
No the heads are definitely NPI they are tulip shaped and the motor is definitely NPI but we were thinking maybe someone already put cams in and he has some kind of aftermarket cam. We cant find a part number any where on the cam and the lift looks the same as the PI cam but I mean it could just be a regular NPI cam with no part number.

I think were just going to have to get a micrometer to be sure
 
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