from the Howard Catalog

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Wyrmrider

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pg 306 this is wrong for a stock rocker and very wrong for the roller rocker shown
many other grinders are the same
for a much better analysis go to the B3RacingEngines.com and read the tech reports
VALVE TRAIN GEOMETRY Valve Train geometry is when the rocker arm tip moves from the intake side of the valve stem tip, across the center of the tip (at approximately mid lift), to the exhaust side of the valve stem tip (at full lift) and back.
After you have estimated the required pushrod length using a Pushrod Length Checker, use this guide to check for proper alignment.
1) The first step is to install a solid lifter and an adjustable pushrod. Mark the tip of the valve with a machinist dye or ink.
2) Install your rocker arm and set it up with zero lash.
3) Rotate the crankshaft clockwise several times. Take off the rocker arm.
The pattern of the rocker tip will be where the ink has been wiped away from the valve tip.
The pattern should be centered on the valve tip. If not, adjust the pushrod length to center the pattern
 
page 298
I notice that howard has some .936 rollers with a .850 wheel (BBC)
for a MOPAR you can bore for .936 (or 1" or 1.030 etc) to clean up worn lifter bores and not bush- but often you have to bush anyway to get a longer travel
now find the lifters for MOPAR SBM will be harder than BBM as top fuel uses the large lifters
 
pg 289 in the paper catalog or 287 Online see the "Direct Lube" hyd lifters
also available from other vendors
But look closely at the flat to the right of the oil hole below the band
this is really easy to do with a v-block on a magnetic chuck grinder
before edm we did it for both hyd and solid FT lifters
it works
 
Take a look at the cam recommendation form on pg 285 online
please gather all the data from this for, or others
I use Jones Racing Cams forms
B4 asking for cam recommendations or calling a camgrinder
will save both of you a lot of time

I was looking at Howard to check on some springs
you can tell a lot about a cam by seeing what springs are recommended
no try and find that information in the Lunati catalog
Voodoo engineering

observation
It looks like howard lets their profiles go a little higher before rolling over for the down side.
Makes the lift look better,
but do you spend enough time, as many degrees up there to make a difference?
and does the sharper pointy lobe which is going to take a bigger spring make a difference?
 
Tnx wyrm...... emphasis on what is wrong is in the last sentence:

"The pattern should be centered on the valve tip. If not, adjust the pushrod length to center the pattern"
 
Wyrmrider said:
Take a look at the cam recommendation form on pg 285 online
please gather all the data from this for, or others
I use Jones Racing Cams forms
B4 asking for cam recommendations or calling a camgrinder
will save both of you a lot of time

I was looking at Howard to check on some springs
you can tell a lot about a cam by seeing what springs are recommended
no try and find that information in the Lunati catalog
Voodoo engineering

observation
It looks like howard lets their profiles go a little higher before rolling over for the down side.
Makes the lift look better,
but do you spend enough time, as many degrees up there to make a difference?
and does the sharper pointy lobe which is going to take a bigger spring make a difference?
Click to expand...
Wyrm.. do you think the pointy lobe is the cause for a heavier spring.... or for the maximum steepness of the ramps? I tend to think the latter (setting the spring at the max acceleration point to avoid severe internal spring vibrations) but am open to info & thoughts. Tnx.
 
valve float over the nose
I know the Jones Motorhome cam gets up to around 300 cam lift and then dwells there- he could have made it a higher lift cam
the 440 heads stock do not flow any more over 450 or so so no use stressing springs
I've posted elswhere where the Jones has 50% more duration at .275 than the longer DC 260 cam- figure where the piston is where this dwell is around the ICL

I've posted before where setting the rocker shaft low causes the perpendicular to the valve stem to be low and that is where the maximum ratio is and the maximum leverage/ acceleration- just where the grinder is trying to slow down the valve so he can start closing it.
With proper geometry you can use less spring or make the spring the camgrinder recommended work
Harvey Crane is simplistic when he says to open immediately and close immediately
he's trying to make a point
The other important design factor IMHO is the close so there is no valve bounce
but there is more to it than just putting in a bigger spring
Actually the intake charge has mass and velocity which you want to make last as long as possible after bottom dead center where the piston is stopped.
If you hold the valve open too far as the piston is coming up you loose your velocity, you want the close ramp to work for you
and a long rod engine ha the piston come up faster, in earlier degrees, than a short rod engine
back to your comment
you do not need the bigger spring till you start to slow the valve down before you go over the nose and when you go over the nose you have to have enough pressure all the way down
 
With the weight of the air/fuel charge, it should still be rushing in after the piston is at BDC on its way up. It gets way more complex than that simple, “What it should be doing” statement.

Funny Wyrmrider mention Harvey Crane.

Your idea of a bigger lift bore to use a greater diameter roller wheel is a bit beyond normal guys wallets and plans I think. Not knocking the idea. I just wonder where it stops?

Wyrmrider, why did you short explain the pushrod length issue and the rocker tip description?
IE;

Where the tip should be to start.
Direction of travel on to long or short of a pushrod.
Etc....
 
Rob
given you have a worn out block and need lifter bore work just drilling out the lifter bores is cheaper than bushings
at least for the chevies and fords
too bad the large olds lifters are not readily available

see B3's 4th tech tip for a discussion of pushrods
with the angle of the SBM lifter bore longer pushrod is even more important

Harvey Crane really shookup the small click of LA Camgrinders
remember when he offered to "computer smooth" competitors masters
all tough in cheek inferring that that the grinders who were mostly doing no r&D were selling jerky cams
And he was right
Early Howards and some others (Ak Miller) were BRUTAL
others like ISKY were really long and gentile and hid the duration by using high checking numbers like .009 and 010 for hyd cams Isky did not like failures, returns
Many times he gave us replacement cams no questions asked- kept the customers happy
Isky's later Megacam series revs really well, and lasts and uses a different checking height on the opening ramp than the closing ramp- go figure
we sold a lot of them
Racer Brown, Winfield, Clay Smith, Bill Jenks (Potvin) new what they were doing) Chet Herbert was smart, Crower always had quality
Nobody any better than Dick Jones

On the flowing ABDC makes a big difference between WOT race motor and street
Looks like VVT is finally here
but my point was you do not want to pop the intake open immediately, rapidly or close it as late as possible and slam it shut- you get more flow mataching header and piston demand on the opening and energy/ velocity/ mass on the close
cheer
I'm gone for awhile
 
LMAO! I do remember when Crane ran that “computer smooth” advertisement! Oh man! Memories!

But I figured you would expand on the pushrod length issue more than just way to read this **** over here and have your head exploded! LOL

I think going to a larger litter bore, as it seems you were advocating to do, is a bit much for the average guy much less the budget fellas.
 
the lifter bore thing is for two needs
one is one who needs to fix block
the other is someone is some class that is heads up where every advantage is needed
 
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