348 Valve Clearance

shotrod34

Member
Is there any need to check the Valve clearance on my 348.
This is what I have:
348 .060 over
10:5 Forged Pistons
Show Cars 0951 Comp Hydraulic Cam .530 intake and .535 exhaust valve lift
Scorpion Roller Rockers Arms 1.75-7/16
Edelbrock Aluminum Heads

Do I need to worry about Clearances?

I was wanting to install my heads and final torque them but I don't have my pushrods yet, so I can't check my clearance.

Valve to Piston should be fine with the 10.5 pistons but I concerned about the exhaust valve to the bore.

Should I be concerned?
 

Tim

Well Known Member
Supporting Member 4
I had 817 heads with roller rockers and the 951 cam and all the rockers hit the stamped factory valve cover. Used a 3/8 cork gasket and spacers from Show cars and now they don’t hit. Don’t know if the eddy heads have a taller cover flange than stock heads though.as for valve clearance I’m not sure. I used KB icon forged but my 348 block has double notches. Lots of clearance
 

63 dream'n

Well Seasoned Member
Supporting Member 4
I had 817 heads with roller rockers and the 951 cam and all the rockers hit the stamped factory valve cover. Used a 3/8 cork gasket and spacers from Show cars and now they don’t hit. Don’t know if the eddy heads have a taller cover flange than stock heads though.
He’s asking about the exhaust valve to the cylinder wall clearance........ I can remember reading that at about a 550 lift cam the valve makes contact with the cylinder wall in a 409 car block ..... I don’t know specifically about 348’s..... do you have compression lowering notches ........you’re pretty wide with your .060 overbore .......but I would wait for Professor Jack’s to stop in, and give you the yeah or nay...!!!!
 

El Rat

Well Known Member
Note: Scorpion rockers are “end” specific. I.E two rockers on each head are scalloped to clear the VC at the end.
I should have said my Scorpion rockers were scalloped. Me bad!
 
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