NV Dual intake cam swap

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Yoshi
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NV Dual intake cam swap

Postby Yoshi » Fri Dec 16, 2011 7:23 pm

I've read a bunch of speculation about this on the interwebs. Someone told me to just eyeball it. Decided that was a laughable option. So here is what I did:

First, get yourself a dial indicator. Like this one:
http://www.amazon.com/Fowler-Magnetic-B ... B002Z312H0
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Second, you NEED the stock exhaust cam and all that goes with it. Then you need your second intake cam. you need to use the stock exhaust cam tray as the intake cam doesn't fit or line up with the oil holes. So essentially, you're only replacing the cam. Nothing else.

So here's the procedure.

1) Install both stock cams. Torque everything down as you would normally. Time everything to TDC.

2) Fix the dial indicator to the engine some way it won't move. Fab a bracket or something. You need to make sure this sucker doesn't move. I used the #3 cam lobes as my reference lobe as it was in the best position to remove the cams without interfering with the dial indicator.

3) Measure out on the dial indicator so it's in the exact spot of peak height for the #3 cam lobe. IE if you turn the cam to the right of left, the gauge will read LESS. There is a slight 'dead zone' where the cam will not move the indicator. Aim for the middle of this.

4) Remove the stock exhaust cam CAREFULLY. Do not hit the dial indicator or you'll have to start all over again. Install the new exhaust came (aka intake cam).

5) Turn the cam so it reads like the stock exhaust cam.

6) Receive bacon.

Caveats: I haven't started my motor yet so I'm not sure if I got it 100% correct. I turned the motor over by hand and I def haven't hit any pistons so I'm reasonably sure I'm within a degree of accurate.

Also, the intake cam's cam sprocket sticky outy thing barely has enough space for the cam gear and the crank/cam gear. You'll have to do your best to line those up. It took me a while.

Remember to rotate the crank twice and make sure all the marks line up properly.
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Status: HG repair. 488wtq though!
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Rick
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Re: NV Dual intake cam swap

Postby Rick » Sat Dec 17, 2011 1:28 am

Interesting using the intake cam on exhaust as well. What are the benefits and difference between them?
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mvrk10256
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Re: NV Dual intake cam swap

Postby mvrk10256 » Sat Dec 17, 2011 1:34 am

Supposedly the duration is the same but one cam has 11.5 vs 11 lift. Only slightly noticeable. Might be worth it if its cheap, especially if you got everything apart. Also the NVM50 are the hottest nonM cams.
-Maksim

Need a project for the weekend? Search "MVRK" - 11 Sticky DIY's and counting....
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Yoshi
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Re: NV Dual intake cam swap

Postby Yoshi » Sun Dec 18, 2011 8:58 pm

the intake has a better lift AND duration. I just don't remember the specifics. IIRC a non vanos intake cam is the same as an S52 intake or exhaust cam. Don't remember which.
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Status: HG repair. 488wtq though!

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