i need help w/duster engine

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mopar melissa

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florida
its a 360
i need help finding out how much valve clearence to piston i have.

i have a 40 over 360 with Kieth Black pistons..#107
360 engine with stock original type heads..
2.02 valve intakes..
my dad machined the heads 2 times..2 layers off...
we had 185 psi in the compression test on all 4 cylinders.
i have crane gold rockers.. 1.5 to one..
i want to put a .600 lift roller cam in it..and dont know if i have
enough piston to valve clearence...or is the cut out in the piston big
enough....?
do any of you guys have this engine or these pistons?
will they work with this cam shaft?
my father is out of state working and i want to put it back to gether
before i get old...
i need help..
thanks..
Mel.
 
Do you have the cam specs.? This is what will make the difference in the valve to piston clearance. Centerlines, lift, and duration at .050.
 
Will you need to have the valve guides and seats machined to run the springs? Only way to check the clearance, now that the heads have been cut, is to install everything, and clay it.
 
we havent picked one out yet..
the old one is

Purple Shaft Cam & Lifter Kit
Adv. Duration: .292°/292°
Dur. @ .050'': 248°/248°
Lift: .509''/.509''
Centerline: 108°
Basic RPM: 2600-6000 RPM
Bolt Pattern: 1-Bolt

i have Doug Herbert roller lifters..was shopping his site..
but ...i dont know exactly what to get...
i really want to put a roller cam in it...
mel.
 
But you don't even know the clearance with that cam- the heads have been machined. And difference in duration, lift, ramp; change the clearances.
 
green1 said:
Will you need to have the valve guides and seats machined to run the springs? Only way to check the clearance, now that the heads have been cut, is to install everything, and clay it.
Click to expand...

the engine is together now...
well.....the heads arent off anyway..i have lifters in #1 piston..
no intake manifold is on it..but i put pushrods back in the #1 piston.
and did a rotation check.. 10 degrees before top center and ten degrees
after..and i pushed the valve down with the adjuster and a diag gauge on the spring retainer to see how far it would do down ..
i measured it...i can look for the numbers..
i ll have to call my dad ...to ask where the sheet is.
mel..
 
The theory is good, but I think it is impossible to calculate where the piston is, compared to where the valve is, trying to factor in duration.
This is why clay is used.
 
green1 said:
But you don't even know the clearance with that cam- the heads have been machined. And difference in duration, lift, ramp; change the clearances.
Click to expand...

this is exactly why i am asking....

if i had the clearence numbers of this cam..id have some idea.

this is what i have now
INTAKE VALVE (standard lenght 2.02 mopar)
.323" @ 10* btdc
.305" @ 10* atdc
.645" max lift to coil bind (with piston out of the way)
exhaust valve (standard length mopar)
.395 @ 10* btdc
.360 @ 10*atdc
.665 max lift to coil bind (with piston out of the way).


i put the crank at 10 drgrees then i loosend the adjuster so the valve was seated..
then i set up the dial guage..on the spring keeper. inline with the valve stem.
theni set it at zero..
i then just turned the adjuster until the valve hit the piston..and i wrote down the numbers..
infront of and after on both intake valve and exhaust valve.
now i need to know how much cam i can go with..
Mel.

edit . or should i say is this enough information to figure out how much cam i can put in it?
does this help..?
 
I dunno. I have always run 340 domed pistons with under .49 lift. If I went to .6, I would have to pull a head and use clay-cheaper than new valves and pistons.
Maybe someone with 360 experience will chime in.
 
oh Green1
i will need new springs to go with it...i am sure..
so if i can figure that out ...ill need to buy springs also..
Mel.
 
.600 lift on stock length valves and uncut guides will not work. The piston to valve clearance isn't your biggest worry yet. You will need to address the retainer to valve guide clearance and valvespring coil bind first before you can get to the piston to valve clearance. Which by the way is not going to be enough either if it even turns over.

That is way too much cam for that engine anyway, besides that you'll probably need to block the oil to the left bank lifter galley and tube the right bank galley and redrill the oil feed holes to the mains because roller lifters will uncover the holes used to oil hydraulic tappets (not needed on solid flat tappet and roller cams) causing a severe loss of oil to the crankshaft and the severe, nay, catastrophic engine damage that will ensue.

Those heads are probably not going to flow any more air past about .480 lift anyway so anything over that just screws up the air flow and you'll end up with severe exhaust reversion back into the cylinders and intake path. The engine will make less power and run like total crap.

If you need any more reasons not to install that cam just ask, I have plenty more.
 
is this a street car or race car....

gonna need alot to make that big roller work...beside valve to piston clearance...

gears..converter...
 
Guitar Jones said:
.600 lift on stock length valves and uncut guides will not work. The piston to valve clearance isn't your biggest worry yet. You will need to address the retainer to valve guide clearance and valvespring coil bind first before you can get to the piston to valve clearance. Which by the way is not going to be enough either if it even turns over.

That is way too much cam for that engine anyway, besides that you'll probably need to block the oil to the left bank lifter galley and tube the right bank galley and redrill the oil feed holes to the mains because roller lifters will uncover the holes used to oil hydraulic tappets (not needed on solid flat tappet and roller cams) causing a severe loss of oil to the crankshaft and the severe, nay, catastrophic engine damage that will ensue.

Those heads are probably not going to flow any more air past about .480 lift anyway so anything over that just screws up the air flow and you'll end up with severe exhaust reversion back into the cylinders and intake path. The engine will make less power and run like total crap.

If you need any more reasons not to install that cam just ask, I have plenty more.
Click to expand...


this is what i have now
INTAKE VALVE (standard lenght 2.02 mopar)
.323" @ 10* btdc
.305" @ 10* atdc
.645" max lift to coil bind (with piston out of the way)
exhaust valve (standard length mopar)
.395 @ 10* btdc
.360 @ 10*atdc
.665 max lift to coil bind (with piston out of the way).

i know we have the guides cut down..atleast enough to go .645" unless my proceedure was wrong..

i have a 9.99 cert duster..race only it goes 6.91 now but thats barely faster than my dragster was..
so i am looking to build it faster..
its got all the good stuff.. trans=brake. spool. 10.5 slicks
more if you need more info... the car can take it..i spent alot on it..
i just want to make this engine make it go faster..
2 similar cars i know of are faster..
i asked them what they had for camshafts and they are .600" or more.

this is what i am trying to do..
Mel
 
70aarcuda said:
is this a street car or race car....

gonna need alot to make that big roller work...beside valve to piston clearance...

gears..converter...
Click to expand...

its got an 8" 5k from Kenny Ford in ala.
I have a 4.30 in it now...with the 29" tire.
but i have 4.56 if i need it..?

the heads flow to .600" or lets say..they didnt drop off till after that..on
the flow sheet...my uncle ported them..they are ta/X cast iron heads..

mel.
 
i have to go to bed soon..
can you tell me what i should do....need to do
ill check back after school tomorrow..
thanks
Mel.

edit..
one last thing.i got the lifters already from Doug Herbert..their tech Guy said " i need to know what your piston to valve clearence is?"
and intake air flow was....
i asked him where i could research this stuff...
he told me to come online here...well go online anyway.....
he said they can build me a cam that won't uncover the oil passage in the lifter...with their lifters?
but i am only goin on his word? basically go with a smaller cam base ..
thanks.. Mel.
 
Well now that we have a little more information we can make a better determination. The problem I see is that getting a spring heavy enough for the roller will not allow that kind of lift with a standard length valve. This is the reason the long valve W2 was developed. All the later performance heads from Mopar have long valves for the 2" installed height valve spring as well. There are things you can do like special retainers to get close to that 2" height but I don't know if that will be enough. You still need .060 left before coil bind at max valve lift.

You will also still need to do the aformentioned block modifications to the lifter galleys so the engine will have to come out and apart anyway. Once you get the head situation correct and the block mods done you can do a mock up assembly of the #1 cylinder and measure your valve to piston clearance, or lack there of. I don't know of any other way to calculate the clearance you'll have even if you had every measurement needed, which you don't, other than an actual mechanical check. You will need to measure through a sweep of typically 10 to 25 degrees BTDC on the exhaust lobe and 10 to 25 degrees ATDC on the intake side. Measuring the cam you have now is futile and doesn't really tell you anything about how much clearance the new roller will have because the rate of lift, duration, open and closing timing events on the roller cam are going to be radically different.
 
Guitar Jones said:
Well now that we have a little more information we can make a better determination. The problem I see is that getting a spring heavy enough for the roller will not allow that kind of lift with a standard length valve. This is the reason the long valve W2 was developed. All the later performance heads from Mopar have long valves for the 2" installed height valve spring as well. There are things you can do like special retainers to get close to that 2" height but I don't know if that will be enough. You still need .060 left before coil bind at max valve lift.

You will also still need to do the aformentioned block modifications to the lifter galleys so the engine will have to come out and apart anyway. Once you get the head situation correct and the block mods done you can do a mock up assembly of the #1 cylinder and measure your valve to piston clearance, or lack there of. I don't know of any other way to calculate the clearance you'll have even if you had every measurement needed, which you don't, other than an actual mechanical check. You will need to measure through a sweep of typically 10 to 25 degrees BTDC on the exhaust lobe and 10 to 25 degrees ATDC on the intake side. Measuring the cam you have now is futile and doesn't really tell you anything about how much clearance the new roller will have because the rate of lift, duration, open and closing timing events on the roller cam are going to be radically different.
Click to expand...

newer roller lifters with solid bodies do not expose the oil galleries anymore...

springs are available for roller cams on standard heads also..
 
That's not what I see on the Doug Herbert web site. Hydraulic rollers, yeah sure, the wheel is much smaller in diameter than a mechanical roller is. And that's the only way you'll get a full bodied roller lifter in there. Same for the springs, hydraulic rollers yes, but if there are springs that are going to handle a radical mechanical roller cam at 1.65 installed height please show them to me. I'd like to see the lifters too if you know who sells them.
 
do you have to go .600+ lift ..? I mean are you hung up on that lift..or are you ok with a more aggressive
roller that is as tall as your current solid cam..but holds the valves events better...
a similar car as your solid for instance in a roller will make more power than what you are now..
and you may or may not need to do a whole lot of modification.
sans springs, pushrods and such.? just a thought
cheapst.
by the way ..6.91 is pretty fast....how fast was your dragster?
 
Besides those roller cams on the Herbert site are smaller than my flat tappet. Although they may make a little more power due to faster ramp speeds but still...
 
Guitar Jones said:
I take it she had a jr dragster.
Click to expand...

no i fugured that...but "not much faster" must have been a fast jr.?

you know i just noticed the heads flow you stated..They flowed to .600"..
what did they flow..? do you have a chart.i doubt they moved much air past the .590 mark...so again you might not need to even go that big..?

cheapst.
 
I don't want to hijack this thread, but as a novice engine builder, I made the mistake of bolting on my heads before I checked the valve-to-piston clearance, and had them torqued and didn't want to take them off, if I could find a way to check the clearance in some other way.

Here's what I did. I'd like to know if this is a viable way to do this...

I bought some very weak (VERY weak) "checking" valve springs and installed them on both valves, for one cylinder. I had already degreed the cam, so I positioned a dial indicator on a magnetic stand, over the retainer/rocker arm, and put a long breaker bar on the socket in the center of the crank, and turned the engine over VERY slowly, and when the crank position was getting close to where valve-to-piston interference might possibly occur, I set the dial indicator to zero, and used physical pressure (it didn't take much; the springs were very weak, as I said) to push the valve further down until it touched the top of the piston, noting the distance beyond where the cam had positioned it. Then, keeping minimal pressure on the valve, holding it gently downward, against the piston, I had someone else very slowly, turn the crank, and watched the dial indicator closely, to ascertain the minimum amount of valve clearance I'd have at ANY crankshaft position, on both sides of the cam lobe, and on both valves.

As it turned out, it had beaucoup clearance on both valves (dished pistons and a cam that only lifted .525"), but is there any reason why Melissa couldn't use this method, if she gets all her other problems ironed out?

I am asking... I am advocating nothing... just here to learn from others' experience. I have NO experience with this, beyond what I just told you, so any comments and advice will be welcome.

Thanks for listening.:read2:
 
You sure your a girl?.....will you marry me? :grommit:
mopar melissa said:
its got an 8" 5k from Kenny Ford in ala.
I have a 4.30 in it now...with the 29" tire.
but i have 4.56 if i need it..?

the heads flow to .600" or lets say..they didnt drop off till after that..on
the flow sheet...my uncle ported them..they are ta/X cast iron heads..

mel.
Click to expand...
 
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