Author Topic: cheetah cam  (Read 4033 times)

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Offline Nicks

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cheetah cam
« on: January 24, 2014, 11:06:33 pm »
16 hp vanguard stock rods and pistons but if i run  all steel push rods and double valve springs and billet retainers will the cheetah cam work for me? And also if i wanna go a bigger exaust valve what is a good size to start with? Im need help!!!!
Nick Schiveley

Offline Old Goat

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Re: cheetah cam
« Reply #1 on: January 25, 2014, 12:01:23 am »
Stock pistons will be fine. Get a set of the long ARC rods and sand the top of the piston down until it is flush with the top of the deck at TDC. This will eliminate most of the dish in the top of the piston ( with no rings on the piston, the rod installed, the top bearing in the rod and the crank turned to TDC for the cyl you are working on, you can easily slide it down in the cylinder to see how much more you need to sand off. I sometimes just use a belt sander to get it close, making sure to take the same amount off all way around the top and then finish sanding by hand with some finer grit sandpaper on a piece of thick glass.) Just remember, you will need at least .030 clearance between the top of the piston and the head. So if you are using the factory .010 thick tin head gaskets the piston will need recessed into the bore .020 at TDC. If you use .030 thick head gaskets, the piston can be flush with the deck at TDC. Or with a thicker .040 gasket the top of the piston can protrude .010. Double valve springs, billet retainers, steel pushrods and cheetah cam will work good. Stock valves will work good with a little port and polish work in the heads. Make sure you get a ARC billet flywheel, because you will easily be able to turn 8000 rpms with this combination. If you find, or all ready have, a set of the stock oem aluminum rockers they will work fine. The stamped steel rockers will not hold up to the higher rpms.
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Offline willenglish

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Re: cheetah cam
« Reply #2 on: January 25, 2014, 12:49:43 am »
I really worry about cutting the top on a standard piston like that. Dosnt leave much meat over that top ring...and it weakens it considerably. I personally believe in good quality forged aftermarket pistons. Yes...they are more expensive than stock pistons...but at 8,000 rpms, that's sure what I would use. A set of stock pistons aren't cheap either...so its really not that much more of an expense for some insurance.
William L. English, jr.

Offline Old Goat

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Re: cheetah cam
« Reply #3 on: January 25, 2014, 02:56:57 am »
The stock 30 vanny pistons worked fine for me with the top being cut down. You will still have some of the dish left in the very center and there is still a lot of piston left above the top ring. I just went down and measured the ones I ran for 2 years, over 50 races on them, turning WELL over 8000 rpms, and they still look like new. I used the stock thick head gaskets, I believe the compressed thickness is about .040 to .045, and left the piston protrude about .010 from the deck. I don't have my mic, but they measure a hair more than 3/32 from the top edge of the ring groove to the top of the piston.

If he had a 38 vanny then I agree with Will, or I would recommend getting 40 intek pistons, which are flat tops.
Jim Klauss
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Offline George Herrin

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Re: cheetah cam
« Reply #4 on: January 25, 2014, 08:30:48 am »
william the older 29/30 and 35 pistons can be cut just fine thats what the long arc rods were made to do and allow. Been doing it for years. Back in 2000 thru 2005 when I ran vanny's we did this. Those Vanny pistons are as good as aftermarket piston out there its when vanny's were real vanny's when the name was special and quality was truly above the rest.
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Offline willenglish

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Re: cheetah cam
« Reply #5 on: January 25, 2014, 02:10:51 pm »
The 38 ci pistons were the ones I was talking about. I agree with George about the earlier ones being a better engine. Even the alloy of the aluminum seemed better.
William L. English, jr.

Offline Nicks

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Re: cheetah cam
« Reply #6 on: January 25, 2014, 02:24:40 pm »
Well im gunna do all that for now,with the cam and al steel push rods what is the best valve adjustment to do? 4 and 6 or 6 and 8?
Well im gunna do all that for now,with the cam and al steel push rods what is the best valve adjustment to do? 4 and 6 or 6 and 8?
Nick Schiveley

Offline crazycraftsman

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Re: cheetah cam
« Reply #7 on: January 25, 2014, 04:49:51 pm »
I was told with same set up to run all at .004.
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Offline Nicks

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Re: cheetah cam
« Reply #8 on: January 25, 2014, 08:41:20 pm »
Ok ill try that bud
Nick Schiveley

 

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