1990 Mustang 5.0 302 V8

Johngreg

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Hello,
I’m in the process of finishing up my rebuild for my 90 Mustang 5.0. I’m running stock cylinder heads, my questions are, will I need to use valve lash caps? I’m using new but stock pushrods, rocker arms, hydraulic roller lifters.

And is there a special procedure to set valve lash? Or can I just torque them down as is?
 

Johngreg

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Well someone just told me that maybe I’m missing lash caps that’s why I wanted to confirm. Sent pic. Also what would the procedure be on setting these? Just torque em down?
 

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railroad

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What do you mean? The person who built my heads said the old springs were no good and went with the comp cam springs
You should be good. Just wanted to confirm what your builder said. Too many neglect a set of new and or upgraded springs on these engines.
 

Johngreg

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YouTube is your friend - I didn’t watch this one but do some searching and you’ll be ok - it is easy.

But I was reading online and they said if I use stock rocker arms it doesn’t matter to rotate the crank, just torque em down to 25ft lb at any position?
 

mighty mouse

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But I was reading online and they said if I use stock rocker arms it doesn’t matter to rotate the crank, just torque em down to 25ft lb at any position?
You will not get an accurate torque reading when the pushrod is pushing up on the rocker. You need to rotate the engine and set the rockers when each lobe is at zero lash.

Sent from my SM-G960U using the svtperformance.com mobile app
 

railroad

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Pedestal mount rockers set the lifter preload by the height of the pedestal and matching fulcrum post. This is what you read about, just tightening down all the rockers to 25 ft lbs. You CAN shim the fulcrum to attain a given preload.
On stud mount rockers you will need to rotate the engine, putting the lifter you are adjusting on the base of the cam lobe. With zero lash, between the valve train, most add 1/2 turn to the nut on the stud. You can do this one cyl at a time or observe which cyl have one of the lifters on the cam base. Hope this helps.
 

Johngreg

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Pedestal mount rockers set the lifter preload by the height of the pedestal and matching fulcrum post. This is what you read about, just tightening down all the rockers to 25 ft lbs. You CAN shim the fulcrum to attain a given preload.
On stud mount rockers you will need to rotate the engine, putting the lifter you are adjusting on the base of the cam lobe. With zero lash, between the valve train, most add 1/2 turn to the nut on the stud. You can do this one cyl at a time or observe which cyl have one of the lifters on the cam base. Hope this helps.
So I’m using the stock rockers. I should just torque down without positioning the crank?
 

railroad

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So I’m using the stock rockers. I should just torque down without positioning the crank?
Yes, if your heads have a cast pedestal to mount the rockers on, usually held on by a single bolt. If your lifters have some hydraulic resistance, bolt them down slowly. This will let the oil bleed off and avoid bending something like the push rods or stripping a bolt.
Put assembly lube on all contact points, end of push rods, tip of the valve stem, between rocker and fulcrum. Pour some heavy oil over the valve springs. They heat up more when new and it takes a while for the oil splash to get on them.
 

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