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Hemi problems again.. valve to valve clearance #585908
01/17/10 07:38 PM
01/17/10 07:38 PM
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Rock Springs
Bob_Coomer Offline OP
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Finally got everything mocked up, short block together etc. Despite some trouble with with the rotating assembly, (actually a rod bearing issue).
Well
I talked with a few of some very helpful people on this board, so I decided to do some checking for possible valve to valve issue's. I measured the distance between the valves with the valves on the seat, and didnt like what i found.. Mopar calls for .280-.300 for cams above .700 lift. I had right at .255-.260 or so. So I knew this might be a problem..
Well this cam is has wide lobe centers of 112 LSA, I degree'd and checked the cam and installed it at a 109-110 ICL so its advanced a hair.

Well I was checking piston to valve clearance which is fine By the way...
Anyways
I was checking piston to valve clearance and noticed that the valves during overlap was very close, you can see the valve events pretty good looking through the intake port..How close..Well they didnt touch rotating the engine in the correct direction. But as I rotated the engine back words, I guess the slop in the timing chain etc retarded the cam, or changed the valve events enough that the valves clipped each other...They physically hit one another.. I had those light checker springs installed etc, so I didnt bend any valves etc. Luckily..
So now, I want to run this cam, so I must address the valves/heads to correct this issue. I know I can sink the valves, Should I sink just one valve like .050 or sink them both like .025? The valves are on diff angles so maybe I can gain more by sinking one valve compared to sinking the same amount off the other?

Can the valves them self's be back cut any to gain any radial clearance??
Even if I can take as little as .008-.010 off each valve diameter would help..

Thanks in advise
Bob Coomer




[color:"red"]65 Hemi Belvedere coming soon [/color]
[color:"#00FF00"]557" Indy engine 1.07 60ft 144mph in the 8th 2100 lbs package [/color]
Re: Hemi problems again.. valve to valve clearance [Re: Bob_Coomer] #585909
01/17/10 08:22 PM
01/17/10 08:22 PM
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Bend,OR USA
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Clipping the valves is usally better than sinking the valve seats. Are these new valves? If so maybe grinding the valves a little first may solve the problem, if there real thick at the seat


Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
Re: Hemi problems again.. valve to valve clearance [Re: Cab_Burge] #585910
01/17/10 08:39 PM
01/17/10 08:39 PM
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Boynton Beach, Fl
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Before getting too excited about them hitting i would set the valves up with the intended springs you are going to use, set with lash and then check again (going the correct direction). There will be a bit of deflection in the pushrods and the rest of valvetrain, big cams are a lot of times real close on valves missing each other, but if you do have to adjust i would cut the exhaust valve down slightly.


93 Dodge Stealth - Supercharged 526ci Hemi
93 Dodge Daytona Top Sportsman injected 588 Hemi - plus a lil NOS
67 Hemi GTX (may the 4speed with you!)
Re: Hemi problems again.. valve to valve clearance [Re: Rapid588] #585911
01/17/10 08:51 PM
01/17/10 08:51 PM
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Rock Springs
Bob_Coomer Offline OP
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Quote:

Before getting too excited about them hitting i would set the valves up with the intended springs you are going to use, set with lash and then check again (going the correct direction). There will be a bit of deflection in the pushrods and the rest of valvetrain, big cams are a lot of times real close on valves missing each other, but if you do have to adjust i would cut the exhaust valve down slightly.



My machist actually told me the same thing.

During the time that they were hitting. There was NO head gasket, the valve lash was set to zero. I dont think the head gasket would matter, but the valve lash might make a diff.
But even MP knew it might be problem with large lift and large duration cams..And Ma Mopar called for .300 between the valves with them on the seat...I know for fact I have only .255-.260 max..Si its close. If two years down the road, and I have some valve guide wear..kaboom..its too close for comfort for me really.
I couldnt measure it, but at the closest point it was only .020 inch .025 tops.

Last edited by Bob_Coomer; 01/17/10 08:52 PM.

[color:"red"]65 Hemi Belvedere coming soon [/color]
[color:"#00FF00"]557" Indy engine 1.07 60ft 144mph in the 8th 2100 lbs package [/color]
Re: Hemi problems again.. valve to valve clearance [Re: Bob_Coomer] #585912
01/17/10 09:00 PM
01/17/10 09:00 PM
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Eighty Four, PA
B G Racing Offline
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I would cut a little off each valve first,drop the seats a little second or a little of both.

Re: Hemi problems again.. valve to valve clearance [Re: B G Racing] #585913
01/17/10 09:27 PM
01/17/10 09:27 PM
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Rock Springs
Bob_Coomer Offline OP
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Quote:

I would cut a little off each valve first,drop the seats a little second or a little of both.




I was hoping you would chime in Bob..
I dug out my Old MP engine book, and according to this, are you referring to cutting some off the margin?

Also I wrote down some notes you told me and some angled for cutting...
Quote:

Chrysler recommends .265 for cams in the .600 lift range and .300 for cams in the .700 lift range.Cut the exhaust valve parallel to the stem and cut the intake 29 degrees to valve stem ,or sink the valves.This is what I like about the Indy Legend head with the moved exhaust valve. I would still use a steel gage,the valve can easly cut quite a few .000s into the aluminum.








[color:"red"]65 Hemi Belvedere coming soon [/color]
[color:"#00FF00"]557" Indy engine 1.07 60ft 144mph in the 8th 2100 lbs package [/color]
Re: Hemi problems again.. valve to valve clearance [Re: Bob_Coomer] #585914
01/17/10 10:32 PM
01/17/10 10:32 PM
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Boise
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Moparteacher Offline
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Yea..install the actual springs, set zero lash, pull your pistons and rods, leave the crank, assemble and install both heads on the block.

Now confirm actual v-v clearance with a feeler gauge up reaching through the bottom.

Re: Hemi problems again.. valve to valve clearance [Re: Moparteacher] #585915
01/17/10 10:42 PM
01/17/10 10:42 PM
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Rock Springs
Bob_Coomer Offline OP
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Quote:

Yea..install the actual springs, set zero lash, pull your pistons and rods, leave the crank, assemble and install both heads on the block.

Now confirm actual v-v clearance with a feeler gauge up reaching through the bottom.




I dont think I need too...I know they need work..The Mopar Jury has reached a decision.
If I had .280 between the valves yea..maybe...But Im almost .050 from recommended minimal valve to valve clearance LOL


[color:"red"]65 Hemi Belvedere coming soon [/color]
[color:"#00FF00"]557" Indy engine 1.07 60ft 144mph in the 8th 2100 lbs package [/color]
Re: Hemi problems again.. valve to valve clearance [Re: Bob_Coomer] #585916
01/17/10 11:54 PM
01/17/10 11:54 PM
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moderncylinder Offline
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hey bob i run .900 lift and .260 valve to valve,,,, ma mopar must have missed the boat on me.... the mopar jury must not apply to me..

do not go on assumption.... check your actual clearance with springs, lash up through the bottom of the cylinder,, if you have .025 run it

and pretty much noone runs .300 valve to valve anymore,, unless you are running a 426 with a cam from 1970

Re: Hemi problems again.. valve to valve clearance [Re: moderncylinder] #585917
01/18/10 07:53 AM
01/18/10 07:53 AM
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Great Neck,LI,new york
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Quote:

hey bob i run .900 lift and .260 valve to valve,,,, ma mopar must have missed the boat on me.... the mopar jury must not apply to me..

do not go on assumption.... check your actual clearance with springs, lash up through the bottom of the cylinder,, if you have .025 run it

and pretty much noone runs .300 valve to valve anymore,, unless you are running a 426 with a cam from 1970


Priceless info right there!!I would never have thought......


HEMI-ITIS has no cure.
My condition is fully BLOWN!!
Re: Hemi problems again.. valve to valve clearance [Re: Bob_Coomer] #585918
01/18/10 08:47 AM
01/18/10 08:47 AM
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Charlotte, NC
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Check all the valve to valve measurements on the seat on each chamber. Note the chamber with the closest measurement, pull that piston/rod out and mock up the head/actual valvetrain on that cylinder. See that you have the minimum of .025" as Jeff said at valve overlap. I would leave the intakes alone, and sink/clip the exhausts to get your clearance.

Careful about following the mopar "bible" too much, that info is way outdated.

Re: Hemi problems again.. valve to valve clearance [Re: LSP] #585919
01/18/10 08:57 AM
01/18/10 08:57 AM
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Norwich CT USA
Defbob Offline
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Quote:

Check all the valve to valve measurements on the seat on each chamber. Note the chamber with the closest measurement, pull that piston/rod out and mock up the head/actual valvetrain on that cylinder. See that you have the minimum of .025" as Jeff said at valve overlap. I would leave the intakes alone, and sink/clip the exhausts to get your clearance.

Careful about following the mopar "bible" too much, that info is way outdated.




it says the purple cam is the most powerful cam for a 440

Bob, I would listen to ModernCylinder

Re: Hemi problems again.. valve to valve clearance [Re: Defbob] #585920
01/18/10 09:08 AM
01/18/10 09:08 AM
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Eighty Four, PA
B G Racing Offline
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You can very easily check the clearence with a wire gage through the intake or exhaust port.Listen to whoever,I would look for a minimum of .035.

Re: Hemi problems again.. valve to valve clearance [Re: B G Racing] #585921
01/18/10 02:32 PM
01/18/10 02:32 PM
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sweden
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Are you saying that the int and ex valves in the same cylinder are hitting each other when you turn the motor over only in one diretion?????
How the %#!" is that possible???
Is the cam twisting in one direction?

Re: Hemi problems again.. valve to valve clearance [Re: Bob_Coomer] #585922
01/18/10 03:05 PM
01/18/10 03:05 PM
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Lansing, MI
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MuscleMike Offline
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FYI: odds are you will have intake pushrod clearance issues on #1 &#8. The way they machined those old Mega blocks the intake pushrods hit the block.

Mike @MM

Re: Hemi problems again.. valve to valve clearance [Re: MuscleMike] #585923
01/18/10 03:43 PM
01/18/10 03:43 PM
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B G Racing Offline
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With close center long duration camshafts it is advisable to have a minimum of .280/.290 between the valves on the seat.Jeff may be getting away with .025 at the valve to valve intersecting point and only have .260 between the valves on the seat with the design of cam he is using.I would not and never recommend you use his numbers with that cam I gave you.The slightest deviation could spell disaster, a loose guide,slight varaying position of a guide center,or a side loading of the valve from unstabe or poor geometry.Even a pushrod bind can cause enough deflection in a long valve with a 5/16 stem to cause concern.I'am not doubting Jeff's claim,after all he is the head guru for race applications and especially SS/AH Hemis,and he would know better than any of us.If your that confident in his recommendation go for it,what do you have to loose?I stand buy what I said,I would rather be conservative and safe than be sorry later.Bob your not building a SS/AH granade and trimming or sinking those valve won't kill a 100hp for sure and you will sleep better.What ever you decide,good luck. P.S.FYI, Jeff it is an early style cam.

Last edited by B G Racing; 01/18/10 08:02 PM.
Re: Hemi problems again.. valve to valve clearance [Re: sshemi] #585924
01/18/10 03:58 PM
01/18/10 03:58 PM
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Quote:

Are you saying that the int and ex valves in the same cylinder are hitting each other when you turn the motor over only in one diretion?????
How the %#!" is that possible???
Is the cam twisting in one direction?


Cam does not twist, it is a physcical contact on the overlap of the valves, not unusual with bigger cams on the 426 hemi motors, be very careful when setting the cam up and make sure to check them like what has already been said to do the bigger the lift(.700+ and duration (286+)the more likely you can have a problem


Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
Re: Hemi problems again.. valve to valve clearance [Re: Bob_Coomer] #585925
01/18/10 03:59 PM
01/18/10 03:59 PM
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Besides clipping the valves for clearance, no one mentioned(or I missed it) anywhere about cutting the exhaust valve to 1.900. I agree with BG..old school cams should be set up the old school way. I run a Crane R290 in my 477 and it's clipped with 1.900 exh valves. It wouldn't work(clear) any other way even with moving the cam timing around.

Re: Hemi problems again.. valve to valve clearance [Re: Cab_Burge] #585926
01/18/10 04:13 PM
01/18/10 04:13 PM
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Quote:

Quote:

Are you saying that the int and ex valves in the same cylinder are hitting each other when you turn the motor over only in one diretion?????
How the %#!" is that possible???
Is the cam twisting in one direction?


Cam does not twist, it is a physcical contact on the overlap of the valves, not unusual with bigger cams on the 426 hemi motors, be very careful when setting the cam up and make sure to check them like what has already been said to do the bigger the lift(.700+ and duration (286+)the more likely you can have a problem




But only when turning it over in one direction???

Re: Hemi problems again.. valve to valve clearance [Re: Cab_Burge] #585927
01/18/10 04:16 PM
01/18/10 04:16 PM
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Good luck with it but if it were me I would mock it up as it is going to be run, lash, springs and all. Then see what you get. BTW the comment about the block and pushrod clearance is spot on, it is gonna need some grinding, even my World block needed a little with an appropriately sized pushrod.


"I am not ashamed to confess I am ignorant of what I do not know."

"It's never wrong to do the right thing"
Re: Hemi problems again.. valve to valve clearance [Re: 52savoy] #585928
01/18/10 04:32 PM
01/18/10 04:32 PM
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Quote:

Besides clipping the valves for clearance, no one mentioned(or I missed it) anywhere about cutting the exhaust valve to 1.900. I agree with BG..old school cams should be set up the old school way. I run a Crane R290 in my 477 and it's clipped with 1.900 exh valves. It wouldn't work(clear) any other way even with moving the cam timing around.





Hi,
I ran the old R290 (I still have it)years back also, I assembled the motor with out pistons and rods, with everything just the way it would run and checked it that way, I back cut the intakes and clipped the exh diameter till I had about .050 between the valves at full overlap.
Russ

Re: Hemi problems again.. valve to valve clearance [Re: old_racer] #585929
01/18/10 05:57 PM
01/18/10 05:57 PM
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Bob_Coomer Offline OP
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Quote:

Quote:

Besides clipping the valves for clearance, no one mentioned(or I missed it) anywhere about cutting the exhaust valve to 1.900. I agree with BG..old school cams should be set up the old school way. I run a Crane R290 in my 477 and it's clipped with 1.900 exh valves. It wouldn't work(clear) any other way even with moving the cam timing around.





Hi,
I ran the old R290 (I still have it)years back also, I assembled the motor with out pistons and rods, with everything just the way it would run and checked it that way, I back cut the intakes and clipped the exh diameter till I had about .050 between the valves at full overlap.
Russ




Yep
Thats what were are shooting for at least .040+ I know guys run them closer, I also know those guys service there engine a bunch more frequent also. I bet they dont go season, after season without refreshing the heads etc...Being a bracket engine, a few seasons with hundreds or runs..Guide clearance gets loose .003-.004 or so, and the bottom see's .008-.010 movement..kaboom. Its probably no big deal to those guys, if they kill a piston, or knock the head off a valve..they have deep pockets..I dont however..

The heads and valves are over to the machine shop now. He said the margins on these new valves were super thick and were +.080..He is going to gauge the clearance, then cut the margin down to about .040-.050 backcut the valve again, and see what he gained by doing this..If he gets a desent return he will do them all. I will then mock it back up and measure actual clearance between the valves during over lap.. We are looking for .040 minimal, or he will sink the exh valve some to achieve what I want...


The one cam I have is probably a 1970 Crane grind that has a narrow 104 LSA..I might try it in this long stroke engine just too see what and how it runs, just for experience. As for the .290-.300 I may not be able to get those margins, but I wished I had them. If it worked back then, it will work now..no matter how out dated it is. I have several intakes,cams, and I plan to just have fun, and test some parts out..


[color:"red"]65 Hemi Belvedere coming soon [/color]
[color:"#00FF00"]557" Indy engine 1.07 60ft 144mph in the 8th 2100 lbs package [/color]
Re: Hemi problems again.. valve to valve clearance [Re: Bob_Coomer] #585930
01/18/10 06:19 PM
01/18/10 06:19 PM
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Eighty Four, PA
B G Racing Offline
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Quote:

Quote:

Quote:

Besides clipping the valves for clearance, no one mentioned(or I missed it) anywhere about cutting the exhaust valve to 1.900. I agree with BG..old school cams should be set up the old school way. I run a Crane R290 in my 477 and it's clipped with 1.900 exh valves. It wouldn't work(clear) any other way even with moving the cam timing around.





Hi,
I ran the old R290 (I still have it)years back also, I assembled the motor with out pistons and rods, with everything just the way it would run and checked it that way, I back cut the intakes and clipped the exh diameter till I had about .050 between the valves at full overlap.
Russ




Yep
Thats what were are shooting for at least .040+ I know guys run them closer, I also know those guys service there engine a bunch more frequent also. I bet they dont go season, after season without refreshing the heads etc...Being a bracket engine, a few seasons with hundreds or runs..Guide clearance gets loose .003-.004 or so, and the bottom see's .008-.010 movement..kaboom. Its probably no big deal to those guys, if they kill a piston, or knock the head off a valve..they have deep pockets..I dont however..

The heads and valves are over to the machine shop now. He said the margins on these new valves were super thick and were +.080..He is going to gauge the clearance, then cut the margin down to about .040-.050 backcut the valve again, and see what he gained by doing this..If he gets a desent return he will do them all. I will then mock it back up and measure actual clearance between the valves during over lap.. We are looking for .040 minimal, or he will sink the exh valve some to achieve what I want...


The one cam I have is probably a 1970 Crane grind that has a narrow 104 LSA..I might try it in this long stroke engine just too see what and how it runs, just for experience. As for the .290-.300 I may not be able to get those margins, but I wished I had them. If it worked back then, it will work now..no matter how out dated it is. I have several intakes,cams, and I plan to just have fun, and test some parts out..





Your astute wisdom reflects your age Gather all the information and make the best decision that will serve your purpose.

Re: Hemi problems again.. valve to valve clearance [Re: Bob_Coomer] #585931
01/18/10 07:52 PM
01/18/10 07:52 PM
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I wouldn't even try that Crane with that LSA, it will make the EGT go sky high and loose a lot of the intake charge and compression out the exhausts I did try a Crane R292-R296 (marine grind )on 108 LSA in a 12.5 to 1 comp. ratio 426 cross ram motor with Bauman SS Carbs and that rascal wouldn't start to run until 4400+ RPM, not good for a bracket motor or a street motor I tried to talk the customer out of using that cam but he had to have try it


Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
Re: Hemi problems again.. valve to valve clearance [Re: B G Racing] #585932
01/18/10 10:32 PM
01/18/10 10:32 PM
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moderncylinder Offline
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i know its an old cam bob,, something for a 426 sized motor,, with a 3.75 stroke,, i know its totally the wrong cam for bob but i think he got it for free or something like that..


you DO NOT need that much overlap with a sroker motor due to the less dwell at tdc respective to stroke travel, more overlap helps to scavange intake charge while the piston is moving about tdc, higher rod ratios need more overlap due to more dwell time for their respective stroke. i dont know what your cam is,, i forgot but i though it had like 72-74 degrees of overlap at .050,,, you would be better with 60 or so,,, maybe even 55 with a 572

"it worked back then so it will work today",,, sure the engine will start and run,, will it be the best cam, or close to it,, not even close,, you will "waste" alot of charge out the exhaust due to overscavaging cause,,,,,,,,, drumroll please.... what cab said.... it has too much overlap,, and if you had less overlap, youd have more valve to valve and youd be fine,, if you had the appropriate cam for your combo...

i understand getting things for free, and wanting to learn yourself that when you do what people tell you to it runs faster,,, im sure it wont be much of a headacche to just clip the margins,, i would not face them,, airflow would be better if you clipped them

Re: Hemi problems again.. valve to valve clearance [Re: moderncylinder] #585933
01/18/10 10:44 PM
01/18/10 10:44 PM

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bob, get rid of the cam and get the correct one, look at the big picture! its not really free when you have to go through all of this to get it to work, plus the cam isnt the right one for your application.
listen to jeff.

Re: Hemi problems again.. valve to valve clearance [Re: moderncylinder] #585934
01/18/10 10:53 PM
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Jeff, what sort of LSAs are they running now in SS/AH? I've heard something around 112, but that was a few years back.


Floyd Lippencott IV
Re: Hemi problems again.. valve to valve clearance [Re: Bob_Coomer] #585935
01/18/10 11:07 PM
01/18/10 11:07 PM
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bob it has always been that you need .250 between the valves so they dont hit each other.

Re: Hemi problems again.. valve to valve clearance [Re: moderncylinder] #585936
01/19/10 04:17 PM
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Quote:

i know its an old cam bob,, something for a 426 sized motor,, with a 3.75 stroke,, i know its totally the wrong cam for bob but i think he got it for free or something like that..


you DO NOT need that much overlap with a sroker motor due to the less dwell at tdc respective to stroke travel, more overlap helps to scavange intake charge while the piston is moving about tdc, higher rod ratios need more overlap due to more dwell time for their respective stroke. i dont know what your cam is,, i forgot but i though it had like 72-74 degrees of overlap at .050,,, you would be better with 60 or so,,, maybe even 55 with a 572

"it worked back then so it will work today",,, sure the engine will start and run,, will it be the best cam, or close to it,, not even close,, you will "waste" alot of charge out the exhaust due to overscavaging cause,,,,,,,,, drumroll please.... what cab said.... it has too much overlap,, and if you had less overlap, youd have more valve to valve and youd be fine,, if you had the appropriate cam for your combo...

i understand getting things for free, and wanting to learn yourself that when you do what people tell you to it runs faster,,, im sure it wont be much of a headacche to just clip the margins,, i would not face them,, airflow would be better if you clipped them




Jeff, No one was trying to undermine your wisdom.

I never said and I don't believe anyone else did either that "it worked back then so it will work today",,, . It was just trying to get Bob on the right track with that old cam profile. I do think his best choice is like you and a couple others have said...buy a new cam profile for a motor that size. But I take him at his word that he wants to use it and know how to set it up.

peace brothers

Re: Hemi problems again.. valve to valve clearance [Re: 52savoy] #585937
01/19/10 05:12 PM
01/19/10 05:12 PM
Joined: Jul 2005
Posts: 1,162
s e mich
ro23car Offline
super stock
ro23car  Offline
super stock

Joined: Jul 2005
Posts: 1,162
s e mich
id buy a bigger rubber band

Last edited by ro23car; 01/19/10 05:13 PM.
Re: Hemi problems again.. valve to valve clearance [Re: 52savoy] #585938
01/19/10 08:23 PM
01/19/10 08:23 PM
Joined: Nov 2003
Posts: 6,293
Rock Springs
Bob_Coomer Offline OP
master
Bob_Coomer  Offline OP
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Rock Springs
I just dont think the cam is way off in left field for the engine..I wished it was about 5 deg smaller on both the intake and exh side as for as duration goes...I like the 112 LSA etc.

The cam is 290°@.050 on the intake and 300°@.050 on the exh looks like overlap is about 71 deg or so. I degree'd the cam in at 109.5-110 LSA which worked out to be exactly what the cams valve events written on the cam card. I liked the fact that the lift at the valve retainer was .775 for the intake and .755 for the exh.

I would love to know how much they can move this cam on a regrind. They probably couldnt tell me unless it was sent in and they knew things like hardness depth etc. Id say .010-.015 would be max they could move whats there including the base circle. Anyone know for sure or have any cam experience?
Looking at Comps Master Cam lobe library..I still would be looking at numbers in the mid 280's on the intake and low to mid 290's on the exh, with about the same LSA give or take a degree or so.

probably a DR or XR intake Lobe and a XCX or JX exh lobe.

Yep
Its a money thing now, buying parts twice is what has hurt me...Changing directions during the build, and not doing my home work has cost me time and money.
Things like Cam, lifters, valve springs,retainers, spring cups, cams, intakes, and even valve covers. But one way or another, the engine will be finished and running well. Even if things are optimal for my combo..They can be changed, I never cared to work on my stuff. I have even been known to take apart good engines for no apparent reason..just too have a look. So labor around here doesnt cost about $0.25 per/hour.


[color:"red"]65 Hemi Belvedere coming soon [/color]
[color:"#00FF00"]557" Indy engine 1.07 60ft 144mph in the 8th 2100 lbs package [/color]
Re: Hemi problems again.. valve to valve clearance [Re: Bob_Coomer] #585939
01/19/10 09:47 PM
01/19/10 09:47 PM
Joined: Aug 2009
Posts: 2,042
Mooresburg, Tn
'
'72CudaRacer Offline
top fuel
'72CudaRacer  Offline
top fuel
'

Joined: Aug 2009
Posts: 2,042
Mooresburg, Tn
Quote:


So labor around here doesnt cost about $0.25 per/hour.



Bob,
I never said I was going to work on your engine. (thats what my wage works out to be)
Brian

Re: Hemi problems again.. valve to valve clearance [Re: Bob_Coomer] #585940
01/20/10 11:14 AM
01/20/10 11:14 AM
Joined: Dec 2005
Posts: 4,231
State of retirement
5
52savoy Offline
master
52savoy  Offline
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5

Joined: Dec 2005
Posts: 4,231
State of retirement
Quote:

I just dont think the cam is way off in left field for the engine..I wished it was about 5 deg smaller on both the intake and exh side as for as duration goes...I like the 112 LSA etc.

The cam is 290°@.050 on the intake and 300°@.050 on the exh looks like overlap is about 71 deg or so. I degree'd the cam in at 109.5-110 LSA which worked out to be exactly what the cams valve events written on the cam card. I liked the fact that the lift at the valve retainer was .775 for the intake and .755 for the exh.

I would love to know how much they can move this cam on a regrind. They probably couldnt tell me unless it was sent in and they knew things like hardness depth etc. Id say .010-.015 would be max they could move whats there including the base circle. Anyone know for sure or have any cam experience?
Looking at Comps Master Cam lobe library..I still would be looking at numbers in the mid 280's on the intake and low to mid 290's on the exh, with about the same LSA give or take a degree or so.

probably a DR or XR intake Lobe and a XCX or JX exh lobe.

Yep
Its a money thing now, buying parts twice is what has hurt me...Changing directions during the build, and not doing my home work has cost me time and money.
Things like Cam, lifters, valve springs,retainers, spring cups, cams, intakes, and even valve covers. But one way or another, the engine will be finished and running well. Even if things are optimal for my combo..They can be changed, I never cared to work on my stuff. I have even been known to take apart good engines for no apparent reason..just too have a look. So labor around here doesnt cost about $0.25 per/hour.




I considered regrinding my R290 a couple years ago but after seeing what Crane wanted to do it, a new cam was cheaper(way).

Re: Hemi problems again.. valve to valve clearance [Re: Bob_Coomer] #585941
01/20/10 11:54 AM
01/20/10 11:54 AM
Joined: Jun 2009
Posts: 705
Michigan
H
Hemiroid Offline
super stock
Hemiroid  Offline
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Posts: 705
Michigan
Quote:

I just dont think the cam is way off in left field for the engine..I wished it was about 5 deg smaller on both the intake and exh side as for as duration goes...I like the 112 LSA etc.

The cam is 290°@.050 on the intake and 300°@.050 on the exh looks like overlap is about 71 deg or so. I degree'd the cam in at 109.5-110 LSA which worked out to be exactly what the cams valve events written on the cam card. I liked the fact that the lift at the valve retainer was .775 for the intake and .755 for the exh.

I would love to know how much they can move this cam on a regrind. They probably couldnt tell me unless it was sent in and they knew things like hardness depth etc. Id say .010-.015 would be max they could move whats there including the base circle. Anyone know for sure or have any cam experience?
Looking at Comps Master Cam lobe library..I still would be looking at numbers in the mid 280's on the intake and low to mid 290's on the exh, with about the same LSA give or take a degree or so.

probably a DR or XR intake Lobe and a XCX or JX exh lobe.

Yep
Its a money thing now, buying parts twice is what has hurt me...Changing directions during the build, and not doing my home work has cost me time and money.
Things like Cam, lifters, valve springs,retainers, spring cups, cams, intakes, and even valve covers. But one way or another, the engine will be finished and running well. Even if things are optimal for my combo..They can be changed, I never cared to work on my stuff. I have even been known to take apart good engines for no apparent reason..just too have a look. So labor around here doesnt cost about $0.25 per/hour.




Bob, I hear ya about money concerns. That being said, I'd really consider a new cam if I were you. It seems really strange that you'd use the wrong cam and go to a lot of trouble(and some $$) in a $20,000+ engine to save $300??

I wish you the best in whatever you decide to do. Love the car and look forward to seeing it make laps some day

Re: Hemi problems again.. valve to valve clearance [Re: Hemiroid] #585942
01/20/10 01:41 PM
01/20/10 01:41 PM
Joined: Dec 2008
Posts: 1,607
KYbywayof WV
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Frito Offline
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KYbywayof WV
Bob, I know you like to go fast, BUT remember, this is a bracket motor not SS/AH. Approach the build as such. I need to get over and look at this baby soon.

Re: Hemi problems again.. valve to valve clearance [Re: Frito] #585943
01/20/10 02:45 PM
01/20/10 02:45 PM
Joined: Nov 2003
Posts: 6,293
Rock Springs
Bob_Coomer Offline OP
master
Bob_Coomer  Offline OP
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Rock Springs
Quote:

Bob, I know you like to go fast, BUT remember, this is a bracket motor not SS/AH. Approach the build as such. I need to get over and look at this baby soon.




Exactly, Thank you..
I know how 10-20 HP will effect a time slip at this level of the game.....There is NO Magic Camshaft or cam selection Voodoo...people might want you to believe so but..If the cam is in the ballpark, how much power...or let me say how much of a diff E/T wise will one see on the time slip? And knowing 15-20HP hardly even changes the slip..well maybe .02-.03 tops


[color:"red"]65 Hemi Belvedere coming soon [/color]
[color:"#00FF00"]557" Indy engine 1.07 60ft 144mph in the 8th 2100 lbs package [/color]
Re: Hemi problems again.. valve to valve clearance [Re: Bob_Coomer] #585944
01/20/10 03:37 PM
01/20/10 03:37 PM
Joined: Dec 2005
Posts: 4,231
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52savoy Offline
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Bob, hopefully this post has lost steam

I talked to Jack Moore(Moore&Moore) over the weekend at the Columbus swap met. He said, he actually ran as good if not better with an old profile cam(R296) in his 572incher.

ain't say'n no'mo

Fred

Re: Hemi problems again.. valve to valve clearance [Re: 52savoy] #585945
01/20/10 07:23 PM
01/20/10 07:23 PM
Joined: Mar 2006
Posts: 9,910
Eighty Four, PA
B G Racing Offline
master
B G Racing  Offline
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Eighty Four, PA
Quote:

Bob, hopefully this post has lost steam

I talked to Jack Moore(Moore&Moore) over the weekend at the Columbus swap met. He said, he actually ran as good if not better with an old profile cam(R296) in his 572incher.

ain't say'n no'mo

Fred





You would be surprized at what those old cams will do if you are dead set on using them.I sent 3 to Bill Stiles a few years back when he was restoring his old P/S car.We had one 528"Hemi that we put in at 101/102 centerline and WOW!!!you think that i wheelstand now and not that my Hemi Dart is anthing close to the new SS/AH techonology nor even competetive,but for a untouched car that was raced last in 1984/85 when it ran the best of 9.97 and still today in it's 1985 old techonolgy with a similar old school cam can still rip of some respectable low 10s with the 30 year old sparkplugs.I respect Jeff's and others knowledge,but I also respect those who can't afford all the new and latest parts,and would be carefull of the advise or information that I gave them.As I have said before,no one is wrong here,just different schools of thought.Bob was given the specs on various cams and he posted them here for everyone's comments and with the information in hand,he made his choise,right or wrong.

Last edited by B G Racing; 01/20/10 07:49 PM.
Post deleted by Defbob [Re: 52savoy] #585946
01/20/10 11:24 PM
01/20/10 11:24 PM

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Re: Hemi problems again.. valve to valve clearance #585947
01/21/10 06:05 AM
01/21/10 06:05 AM
Joined: Mar 2006
Posts: 9,910
Eighty Four, PA
B G Racing Offline
master
B G Racing  Offline
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Eighty Four, PA
Quote:

Quote:

Bob, hopefully this post has lost steam

I talked to Jack Moore(Moore&Moore) over the weekend at the Columbus swap met. He said, he actually ran as good if not better with an old profile cam(R296) in his 572incher.








I still run a 70's Crane it's been in my last 3 motors. I think maybe that the rate of lift in the older grinds was much more severe at lower lifts and could have caused the valve clearance problems.
my cam card

PART 66R000424 ENGINE TYPE: MECHANICAL ROLLER

SPECIAL

GRINDN R-288/4714-2S-10

ENGINE 1966-1971 PLYMOUTH-DODGE V8 HEMI 426 CU.IN.

(THREE BOLT GEAR)

VALVE SETTING: .026 EXHAUST .026 HOT

INTAKE @ CAM
4714 @
740 ROCKER ARM

INTAKE @ CAM
480 @
730 IN 1.57/EX 1.52 ROCKER ARM

LIFT: EXHAUST @ @

ALL LIFTS ARE BASED ON ZERO LASH AND THEORETICAL ROCKER RATIOS

CAM
OPENS
CLOSES
ADVERTISED

.0162 EXHAUS INTAKE 56.0 BTDC 92.0 ABDC 328 ° °



TAPPET LIFT EXHAUS
98.0 BBDC 54.0 ATDC 332 °

SPRING
RECOMMENDED RPM

RANGE WITH

TRIPLE DUAL OUTER MATCHING

PART
99877 MINIMUM RPM 4500

LOAD CLOSE
220 LBS 2.000 O 2" MAXIMUM RPM 9000

OPEN:
592 LBS 1.320 VALVE FLOAT 9600

CAM
OPENS
CLOSES
MAX LIFT
DURATIO

@ .050 INTAKE
37.0 BTDC 71.0 ABDC 105 ° ATDC 288 °

TAPPET LIFT EXHAUS
79.0 BBDC 33.0 ATDC 115 ° BTDC 292 °

IMPORTANT!
Crane Cams continuously improves and upgrades its cam designs. In some cases this may mean that two
Crane Cams with the same part number may actually be different grinds. You must check the GRIND
NUMBER stamped on the front of the camshaft and check it against the Grind Number near the top of the
Spec Card.




Fred is that the cam we put in your 588"?

Post deleted by Defbob #585948
01/21/10 12:26 PM
01/21/10 12:26 PM

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Re: Hemi problems again.. valve to valve clearance #585949
01/21/10 01:43 PM
01/21/10 01:43 PM
Joined: Nov 2003
Posts: 6,293
Rock Springs
Bob_Coomer Offline OP
master
Bob_Coomer  Offline OP
master

Joined: Nov 2003
Posts: 6,293
Rock Springs
Quote:

Quote:

Bob, hopefully this post has lost steam

I talked to Jack Moore(Moore&Moore) over the weekend at the Columbus swap met. He said, he actually ran as good if not better with an old profile cam(R296) in his 572incher.








I still run a 70's Crane it's been in my last 3 motors. I think maybe that the rate of lift in the older grinds was much more severe at lower lifts and could have caused the valve clearance problems.
my cam card

PART 66R000424 ENGINE TYPE: MECHANICAL ROLLER

SPECIAL

GRINDN R-288/4714-2S-10

ENGINE 1966-1971 PLYMOUTH-DODGE V8 HEMI 426 CU.IN.

(THREE BOLT GEAR)

VALVE SETTING: .026 EXHAUST .026 HOT

INTAKE @ CAM
4714 @
740 ROCKER ARM

INTAKE @ CAM
480 @
730 IN 1.57/EX 1.52 ROCKER ARM

LIFT: EXHAUST @ @

ALL LIFTS ARE BASED ON ZERO LASH AND THEORETICAL ROCKER RATIOS

CAM
OPENS
CLOSES
ADVERTISED

.0162 EXHAUS INTAKE 56.0 BTDC 92.0 ABDC 328 ° °



TAPPET LIFT EXHAUS
98.0 BBDC 54.0 ATDC 332 °

SPRING
RECOMMENDED RPM

RANGE WITH

TRIPLE DUAL OUTER MATCHING

PART
99877 MINIMUM RPM 4500

LOAD CLOSE
220 LBS 2.000 O 2" MAXIMUM RPM 9000

OPEN:
592 LBS 1.320 VALVE FLOAT 9600

CAM
OPENS
CLOSES
MAX LIFT
DURATIO

@ .050 INTAKE
37.0 BTDC 71.0 ABDC 105 ° ATDC 288 °

TAPPET LIFT EXHAUS
79.0 BBDC 33.0 ATDC 115 ° BTDC 292 °

IMPORTANT!
Crane Cams continuously improves and upgrades its cam designs. In some cases this may mean that two
Crane Cams with the same part number may actually be different grinds. You must check the GRIND
NUMBER stamped on the front of the camshaft and check it against the Grind Number near the top of the
Spec Card.




That looks real close to my cam specs..Matter of fact overlap is the same..Its the diff between 110 vs 112 LSA...
I recall the youtube video of the Duster...and wow it sounds killer..


[color:"red"]65 Hemi Belvedere coming soon [/color]
[color:"#00FF00"]557" Indy engine 1.07 60ft 144mph in the 8th 2100 lbs package [/color]
Re: Hemi problems again.. valve to valve clearance #585950
01/21/10 10:17 PM
01/21/10 10:17 PM
Joined: Mar 2006
Posts: 9,910
Eighty Four, PA
B G Racing Offline
master
B G Racing  Offline
master

Joined: Mar 2006
Posts: 9,910
Eighty Four, PA
Quote:

Quote:

Fred is that the cam we put in your 588"?



yes not just same grind it was same cam and it was in the 484 " motor when I bought the car back in 1997 then used in the 572 and now your 588" [/quot

Keep in mind Fred you are using Indy Legend heads with the moved exhaust angle and don't have the clearence problem.

Re: Hemi problems again.. valve to valve clearance [Re: B G Racing] #2642022
04/06/19 05:30 PM
04/06/19 05:30 PM
Joined: Jan 2003
Posts: 17,844
S.E. Michigan
ZIPPY Offline
I Live Here
ZIPPY  Offline
I Live Here

Joined: Jan 2003
Posts: 17,844
S.E. Michigan
This was a helpful thread to me many years later, I have .040" measured from the bottom and it seemed
Fine, but I was questioning it.

Thanks for the knowledge shared here.

Zombie thread alert.

Last edited by ZIPPY; 04/06/19 05:31 PM.

Rich H.

Esse Quam Videri




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