Connecting rod orientation

SC Spyder

Registered User
Does anyone know if the SC connecting rods need to be installed in a particular orientation?

I picked up a rebuilt SC engine and I found that all connecting rods are not all installed the same. Some are installed with the stamped numbers toward the outside (exhust manifolds) and some are installed toward the cam side.

I know with a 351w, the rods have an offset and need to be installed in a certian way, does any one knoe if the SC rods are offset?

Doug
 
Rods are typically symmetrical so they can usually go either way. The pistons will be different as the pin hole in the piston is usually slightly offset to deal with thrust forces based on crankshaft direction of rotation.

If it's an early motor, the pin is pressed into the piston. The pistons will have a dot on them near the top edge. The dot typically points towards the front of the block.
 
Ah... thank you I knew it was something like that.

It looks like an 89 engine. I am hoping I can transfer the parts from my 93 to it.

Much Appreciated.

Doug
 
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Yeah...the big end goes down and the small end goes up:D.

I cant say for sure. Some rods are different and I think Mike may have an inside on this so I would go with his advice.

Chris
 
The only other thing I can think of is that some rods had an oil squirter hole that would pickup oil off the crank and then squirt it under the piston skirt. Those could be picky in addition to the pistons.

note this is talk about factory rods for this motor. Other motors and other applications certainly could have rod orientation requirements.

You also want to consider the motor balance. Factory SC motors are internally balanced, If you swap rods, pistons and not the crank you may want to have the motor re-balanced. If you're swapping the crank as well, you'll want to keep track of which rods and pistons are from which holes to try to maintain the factory balance.
 
Ok, so heres what I found, at least all the pistons were pointing in the correct direction, flat side up :D, no really, mark forward.

These are all factory rods and crank (The crank does not appear to have been turned) is in general in good condition, the pistons .030 over .

So, I took a spring punch and marked each rod and cap with its location in the motor. The person I had purchased this from had installed new freeze plugs, new bearing and rings but did not have new cam bearings installed.

I'm not too happy with the feel of the main journals nore the amount of vertical movment on the front of the cam and the cylinder hone so, tomorrow the block, crank and new BHJ balancer will go to the machine shop for new cam bearings, a polish of the main journals, a clean up cylinder hone for the cylinders and fit the balancer to the crank.

Then it's assembly time, and finally get to use all the neat parts I've been slowly buying, mate it to the trans, into the chassis, drop the body back on and try to mate the SC wiring to the existing harness.

Thanks for your help!

Doug
 
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Are they going to verify the main and rod bearing clearances? I would, as you may find clearance so large that it would be better to go grind the crank .010 and do larger bearings. Correct clearance values are extremely important to help maintain proper oil pressure throughout the motor.
 
Yea ... while they have the crank they will measure all the journals and I'll plastigauge everything.
 
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