340 rocker set up???

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Gib Warnick

'65 Valiant signet
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I am getting my mild 340-hydraulic cam ready to install in 65 Signet. Short block and J heads together. Have to get valve train set up- rockers/shafts/push rods/lifters- want to use stock steel rockers
I want to do it once right. Mopar Performance stuff is expensive...
Any recommendation of what you are using? Thanks in advance
 
What cam ,what valve springs , and valve spring pressure,...And the gears , and stick.converter....? We need an honest response ,for an honest answer..
 
Abodybomber said:
What cam ,what valve springs , and valve spring pressure,...And the gears , and stick.converter....? We need an honest response ,for an honest answer..
Click to expand...
Thanks Cam is purple shaft- 282/284 1O:1 Keith Black pistons stock original rebuilt 904 and converter 3.73..
I am interested in new stock style replacement stuff
 
You will need adjustable rockers with that cam. you can use stamp steel but performance will not be at its peak. Larger cams do not have larger lobes they have a smaller base circle which creates more lift. Pre-load is important Keep the lifters a no more than 1/4 turn down from zero lash. some will chime in and say 1/2 to 3/4. That is good for 70's lifters and oil. Comp Cams recomends 1/8. All new flat tappit Hyd. lifters have low quality valving.

Find a set of used 273-318 adjustable rockers buy hydraulic push rods and you will be good. Cheap roller rockers will destroy a motor when the rollers fail and the needles or roller fall into the motor. Those old school adjustable rockers are cheap and will last your lifetime
 
Oldmanmopar said:
You will need adjustable rockers with that cam. you can use stamp steel but performance will not be at its peak. Larger cams do not have larger lobes they have a smaller base circle which creates more lift. Pre-load is important Keep the lifters a no more than 1/4 turn down from zero lash. some will chime in and say 1/2 to 3/4. That is good for 70's lifters and oil. Comp Cams recomends 1/8. All new flat tappit Hyd. lifters have low quality valving.

Find a set of used 273-318 adjustable rockers buy hydraulic push rods and you will be good. Cheap roller rockers will destroy a motor when the rollers fail and the needles or roller fall into the motor. Those old school adjustable rockers are cheap and will last your lifetime
Click to expand...
Use with hydraulic lifters?
 
Oldmanmopar said:
You will need adjustable rockers with that cam. you can use stamp steel but performance will not be at its peak. Larger cams do not have larger lobes they have a smaller base circle which creates more lift. Pre-load is important Keep the lifters a no more than 1/4 turn down from zero lash. some will chime in and say 1/2 to 3/4. That is good for 70's lifters and oil. Comp Cams recomends 1/8. All new flat tappit Hyd. lifters have low quality valving.

Find a set of used 273-318 adjustable rockers buy hydraulic push rods and you will be good. Cheap roller rockers will destroy a motor when the rollers fail and the needles or roller fall into the motor. Those old school adjustable rockers are cheap and will last your lifetime
Click to expand...
This^^^^^
Yes. Use with hydraulic lifters.
 
It is easier to get the correct hydraulic lifter preload by using adjustable rocker arms. But it not the only way. You just have to figure out what exact length pushrods you need and buy them custom made. That's one way you can run stock rocker arms if your heart is set on it.
 
i run same cam in 318, i got all heavy duty pushrods and factory style non adj heavy duty rocker arms from mancini racing, no problem buzzing to 7000 rpm if i wanted to, i moved this gear to my 360 and i havent taken it past 6200,my choice, no way u need adj rockers, unless u want to spend extra $$$$$s, i also picked up new rocker shafts at same time from mancini, good tech service there!
 
Gib Warnick said:
Use with hydraulic lifters?
Click to expand...
I believe Oldmanmopar meant "buy pushrods for adj. rockers", but everything He stated is correct. You can run the stamped units as is w/the stock pushrods, but they will not
be ideal by far. Your options are;
1) check the preload for each valve on one head, and shim the rocker shaft to correct for the one that has the least preload, so that it is ideal. The rest will have more than.
2) use a checking (adjustable) pushrod, check all of the valves and find the one with the longest length to -0- lash, then add .015" to that and get a set of pushrods that dim.
3) get the OE 273 adj. rockers(& shafts) and mech. pushrods, then You can set each valve to the ideal preload, this is Your best choice by far.
 
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Gib Warnick said:
I am getting my mild 340-hydraulic cam ready to install in 65 Signet. Short block and J heads together. Have to get valve train set up- rockers/shafts/push rods/lifters- want to use stock steel rockers
I want to do it once right. Mopar Performance stuff is expensive...
Any recommendation of what you are using? Thanks in advance
Click to expand...

Careful with your set up with that cam. I had almost your exact set up with that cam except with 3.23 gears and it was a dog. Could hardly brake the tire loose with an open rear end while foot braking it. Tried a 2800 rpm converter = dog went to a 3400 rpm converter= worked
 
I meant using 273-318 adjustable rockers with push rods the correct length for hydraulic lifters. They will be ball and cup push rods same as the solid lifter push rods. But they are shorter. This is the way to go for durability and pre-load adjustment. This is the same rockers used on the T/A 340 but the intake rockers were at an angle for the relocated push rod holes in the TA heads. They came with Hydraulic lifters

The early 273-318's are iron rockers and they are adjustable. You can use the inferior fit adjusters they come with or tap them for the lock style.

This by far is the best bang for the buck when it comes to a adjustable rocker arms. Decking the block, cutting the heads, changing the head gaskets to a different thickness. Or Changing the cam. All these changes effect the pre-load on the lifters. Sure guys get away with cheap *** stamped steel rockers. But I have seen many push rods come through them. Then the lifter comes out of the hole and there goes the oil pressure. or the push rod falls into the motor and the cam makes a pretzel out of it.

You can usually pick these rockers up for around $150 to $200 push rods another $80 through summit . I paid over $1700 for my T&D's because of the spring pressure I use. I can't stress how important rockers are. We just finished a 340 motor for a customer. It received those 273 Rockers with a 557 lift Hyd. cam. I have a extra set of push rods if you need them just pay shipping. They won't work with Edelbrock heads because of the Diameter but will work with iron heads.

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Right, once more...
You need to "buy pushrods for adjustable rocker arms", the length would depend on what changes from stock have been if any. Otherwise, using the appropriate OE length
rods, hyd. or mech. will do. Edit time.............
The rule of thumb on them is the right length pushrod will only have the adjuster showing 1-2 threads out of the bottom of the rocker arm, & it's not a bad one. There are
lots of things to check & perfect geometry-wise if You want to go there, but for what You're running, You should be fine.
 
Old Man Mopar is your huckleberry. He has hooked you slam the hell up with great information......no surprises here.
 
Advance the 284 to 100-102 range in a 10:1ish 340. If it's any other than the 108 LSA model, use it as a doorstop. The 108 cam is the ONLY one to use. The wider lobe separation cams are GARBAGE!
 
Gib Warnick said:
Use with hydraulic lifters?
Click to expand...

If you want the push rods let me know. I have others that PM' me for them. They are free if you need them Just pay shipping. I have them left over from another build. They are 11/32 diameter they came with a rocker set but didn't fit with Edelbrock heads. we replaced them with 5/16.

I also have a set of rockers and shafts but no hold down hardware. shafts will need second oil hole drilled at 90 degrees. Let me know today or they are gone. Steve
 
Sorry to hijack, but like OMM advised I am planning on going factory adjustable rockes on 340 with x heads and solid cam.
My question...can I go with factory ball n cup push rods? Or will custom ones be required?
No milling has been done on heads or block.
Thanks
Steve
 
Also depends who did the valve job, I have had friends with issues on different valve tip lengths, where non adjustable rockers would pre load a lifter too much. So adjustable rocker arms helped.
 
4spdragtop said:
Sorry to hijack, but like OMM advised I am planning on going factory adjustable rockes on 340 with x heads and solid cam.
My question...can I go with factory ball n cup push rods? Or will custom ones be required?
No milling has been done on heads or block.
Thanks
Steve
Click to expand...

Maybe... It's best to mock it up and measure.

Different valve tip height on a mopar... yeah not good.

For the OP, the 273 rockers work well with correct length ball/cup pushrods and is the best for factory rockers. The 284 has been run a lot over the years with stock non adj rocker gear as well.
 
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