Build Question

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JimmyV

JimmyV

MOPAR!!
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Hey Guys! this is not A-Body related but it is magnum related.

I am building a 408 magnum for my truck. i got the short block done last year and am getting ready to get the heads done. going with eddy heads.

was going to have my engine guy assemble the long block out but he just wants too much money for something that i can do. but i do have a couple questions related to pushrod length and cam clearance

I am going with a lunati billet solid roller, got it used in great shape from a buddy that ran it in a simular combo. my questions are as follows.

Pushrod length vs cam/valve clearance and checking procedure. in what order should i do this?

something in my head tells me i can check cam clearance with the lifter i am going to run and a couple stock pushrods and then measure for push rod length after that part is all figured out.
but i also dont want to do them in the wrong order. i dont believe push rod length is going to effect valve lift to a point that my reading would be inaccurate to high degree. below is how i am thinking i will approach this, any input would be greatly appreciated


my plan was to slap a head on check valve/piston clearance with some stock magnum pushrods i have laying around, after i get that situated i was going to measure for pushrods. i was planning on doing this with the springs that came with the heads, then swap to the springs for my camshaft after? does these seem like a feasible way to do this?

Thanks in advance!
 
Are you going to run adjustable rocker arms? You're plan as stated is good and always recommended for any build. You also want to make sure that your geometry is correct if running roller rockers. Roller should be centered on the valve stem. 65'
 
Plymouth 65 said:
Are you going to run adjustable rocker arms? You're plan as stated is good and always recommended for any build. You also want to make sure that your geometry is correct if running roller rockers. Roller should be centered on the valve stem. 65'
Click to expand...

yes i will be running comp chrome molly 1.6 rollers....
 
my other question is will stock pushrods work to check valve clearance? i know solid rollers are slightly short compared to hydraulic no?
 
Pushrod length does matters in piston to valve clearance. TDC no.1 piston, adjust pushrod to proper lash cold, rotate engine. Use plastigauge or similar product to measure clearance. 65'
 
Plymouth 65 said:
Pushrod length does matters in piston to valve clearance. TDC no.1 piston, adjust pushrod to proper lash cold, rotate engine. Use plastigauge or similar product to measure clearance. 65'
Click to expand...
Piston to valve clearance should not be checked at TDC as the clearance will be tighter on ether side of TDC. The last thing you want to check is piston to valve clearance - after you have finished picking the rotating assembly, deck height, head gaskets, valve train you are going to run ( including the correct pushrod length as it will effect clearance ), lash. This is easiest done before the short block is finalized and assembled. Mock up one hole using valve clearance checking springs. Rotate the motor over TDC ( at least 25* on ether side of TDC and measure the piston to valve clearance with a dial indicator off the valve spring retainer every few degrees.
 
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