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Discussion Starter · #1 ·
Building a mild 454 with stock 702 closed chamber heads. Have decided on a Howards CL120115-12 cam and lifter kit. I still have a few questions as all of this cam conversion stuff i new to me.

1) Do I have to have a special timing set to work with a thrust button or will any standard double roller set work?

2) What valve springs do I need? Is there a kit? How do I know what pressures and whatnot that I need?

3) Is a Manley 42133 a good way to measure pushrod length?
 

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No, you don't need a special timing set, just any standard double roller is fine. I would suggest a lock plate to serve as a retainer, but once the timing cover is installed there is no way for the cam button to come out of place.

Contact Howards Cams, they can tell you needed spring specs, or even supply the kit with the correct valvesprings.
I would expect to see something like 125-145 lbs seat, 375-450 lbs open pressures

The Manley checker is about worthless, kinda-sorta only works with stock rocker arms....doesn't work at all for setting up roller rocker arms.

Correct method for roller rockers
Push Rod Geometry for Engines - YouTube

Did you by chance mistype the Howards cam #....I could not find 120115-12??....but could find 122115-12.
#122115-12 is 278/288° advertised duration, 225/235° @.050 duration, .595/601" valve lift, 112° Lobe separation, 108° intake centerline.
That the cam you have in mind?
 

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Discussion Starter · #3 ·
No, you don't need a special timing set, just any standard double roller is fine. I would suggest a lock plate to serve as a retainer, but once the timing cover is installed there is no way for the cam button to come out of place.

Contact Howards Cams, they can tell you needed spring specs, or even supply the kit with the correct valvesprings.
I would expect to see something like 125-145 lbs seat, 375-450 lbs open pressures

The Manley checker is about worthless, kinda-sorta only works with stock rocker arms....doesn't work at all for setting up roller rocker arms.

Correct method for roller rockers
Push Rod Geometry for Engines - YouTube

Did you by chance mistype the Howards cam #....I could not find 120115-12??....but could find 122115-12.
#122115-12 is 278/288° advertised duration, 225/235° @.050 duration, .595/601" valve lift, 112° Lobe separation, 108° intake centerline.
That the cam you have in mind?
Sorry about that - the cam I am looking at is the CL120225-12. Should be good for 9.5:1-ish compression and lots of low end torque with a strong mid range?

I will put a call in to Howards on Monday about springs.

Thank you for all your help.
 

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Watched your video about pushrod length, that's way easier than I thought.

One more question, what's a good quality budget friendly set of roller rockers?
Ok, 120225-12, that's a good low end power and midrange cam, should fit what you plan nicely.

For budget rockers, cheap as I'll go is Scorpion....I don't bother with the ebay no-name stainless but have heard of guys having no trouble with the PRW stainless body roller rockers...they are imported however if that changes your feelings about them.
Scorpion is made in the USA and guaranteed.
Scorpion also makes the Howards aluminum rockers for them.

Avoid the rocker type that looks stock but has a roller tip....the rollers need to be in the pivot a lot more than the tip, so you are just wasting money with those type.

The Comp Cams High Energy Die Cast rocker would also be a decent option for your build, since it isn't a full race deal needing billet aluminum or stainless steel.
 

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Discussion Starter · #6 · (Edited)
One thing I didn't hear in the video was how much length to add to the push rod measurement for a hydraulic lifter - how far should the lifter be collapsed?

Also, to degree the cam in I just need a piston stop, degree wheel, and dial indicator, correct?

If you can't tell, this is my first real engine build...
 

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Hydraulic lifter is replaced with a solid if you do enough of these to have some old ones laying around. Tou van solidified a hydrauluc by sliding the innards out and putting washers into the base till the innards install and are held in the anticipated operating position. That would be full up minus the linear dimension that the number of turns you make below the full up against the retainer would make. This is the adjusting screw thread pitch per inch divided by one inch times the number of preload turns you intend to run.

Bogie
 

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Discussion Starter · #8 ·
Hydraulic lifter is replaced with a solid if you do enough of these to have some old ones laying around. Tou van solidified a hydrauluc by sliding the innards out and putting washers into the base till the innards install and are held in the anticipated operating position. That would be full up minus the linear dimension that the number of turns you make below the full up against the retainer would make. This is the adjusting screw thread pitch per inch divided by one inch times the number of preload turns you intend to run.

Bogie
How many preload turns would you suggest?
 

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Ordered everything but the cam - cam is back ordered until the end of February. Is there a comparable make and part number of cam you would recommend?
Virtually every cam company is in the same situation....covid shutdown related manufacturing and shipping delays.....nobody has cam cores to grind because there were only a couple of core suppliers.

If it isn't something they have inventory of on the shelf, you are just SOL until it becomes available again.

The high performance industry in general is really hurting at the present time, parts are in short supply all over.

You could try Jones Cam Design for a custom grind, he is very good.
 
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