[Vsanthos]

I am installing a Crane Cams Roller cam, it is a Hydraulic roller cam, and it's profile is .488 intake, .509 exhaust.

My problem is this: I installed the crank, then put in all the rods and pistons, and everything was fine up until that point. Then, the cam was inserted, it went all the way to the back, without a problem. The problem came when the cam was spun, it struck something. We checked everything for about 15 minutes, and we even tried the old cam that came out of the block, which was a regular hydraulic cam (non-roller).

My question is this: is this just a simple timing problem? Or are more of my parts simply interfering with the cam? Do I need a new cam? or maybe different rods?

P.S: I have Summit Stage II Rods, a summit .020 under crank (anyone know what the point of being 20 under is? it came in the block, and was like new, but I don't know what the difference is for) I hope this is just a timing problem.

Thanks for all input.

[4 Jaw Chuck]

Pull the pan and have a look, let us know what you find. Sounds like your rods are hitting the cam.

The 0.020" crank is how much under the crank was ground, you put 0.020" under bearings in right?

[Vsanthos]

Yes, I have the correct bearings and such, and I just wonder what the purpose of .020 under is.

And the engine isn't all together, the only things in are the pistons, rod, crank, and cam, and I was rotating them by hand. It is the rods hitting the cam, as it looks. The thing I was wondering is, is this hitting because the engine isn't rotating together, and isn't timed, or is it hitting because maybe the cam is a bit too radical?

I tried the cam that was in the old block, and I am using the same crank shaft, so the only thing that could be different, and causing problems, is the rods, but is there any width difference between rods?

[4 Jaw Chuck]

Lets get back to basics, what kind of engine? is this engine being stroked? What kind of rods?, what kind of rod bolts?

It is likely that your rods are hitting the cam because roller cams have a larger base circle than flat tappet camshafts and your new rod bolts have got you into a tolerance stack up, some minor grinding on the offending rod bolts usually clears this up, I need more info to go further.

[Vsanthos]

The rods are 5.7" Summit Stage II, it's just a regular old 350 crank to my knowledge.

The engine is bored .040 over, so it's a 357, it's not stroked. and it's not every time that the cam hits, it's only when the cam and the crank are rotated just right, which is why I am thinking that it is that there is no timing running that this is happening.

Edit: The rod bolts are one piece connectors.

[ April 27, 2002: Message edited by: Vsanthos ]</p>

[4 Jaw Chuck]

The cam chain must be installed and the cam timed or this will happen.

[F-1Rodder]

Vsanthos: I think your cam/timing chain/crank are not properly alligned. That combination should not make contact if properly installed.

[Vsanthos]

The timing gear isn't even on, I tried to make that clear. (not trying to be an *** ) I am using a Pete Jackson Gear Drive, not a chain =) but anyways... I figured it was just a timing problem, I'll try connecting the timing gears. Thanks

[Cobracar]

The cam and the rest of the rotating assembly MUST be timed by a properly located timing mechanism or a conflict between the cam and other portions of the assembly can be expected. The potential for interference increases as the lift of the cam increases. See my post regarding Cam interference with a stroker motor.

[roys63]

I am using the same Summit rods in 2 motors with no problems, one has a 650 lift roller, they have a lot more room on the big end no bolt heads on the topside of the rod.Install chain it will be fine!I think you should lose the PJ geardrive!!

[ October 18, 2002: Message edited by: roys63 ]</p>

[46_stvblt]

Roy's 63. I am curious why you said to " lose the PJ gear drive" Glenn K <img src="confused.gif" border="0">

[roys63]

To much Noise and they rob HP, And Weird Vibrations threw the valvetrain and crankshaft! Just not good for the street with a roller cam!I haven't tryed other types

[ October 19, 2002: Message edited by: roys63 ]</p>

[chevyelc81]

Ive heard that PJ gear drives cause premature cam bearing wear because of the vibrations running through the cam. Plus ive used one before and it got really annoying quick.

[1BAD80]

4 Jaw Chuck knows what hes talking about and a few others.
Look on this site for gear drive posting by Buffed and you will see what everone is talking about. Take the gear drive back and get a chain drive. <img src="graemlins/pain.gif" border="0" alt="[pain]" />