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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Joined: Dec 2003
Posts: 1,401 Wi.
old_racer
pro stock
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pro stock
Joined: Dec 2003
Posts: 1,401
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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
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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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Joined: Nov 2003
Posts: 6,293 Rock Springs
Bob_Coomer
OP
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Posts: 6,293
Rock Springs
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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]
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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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Joined: Mar 2006
Posts: 9,910 Eighty Four, PA
B G Racing
master
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master
Joined: Mar 2006
Posts: 9,910
Eighty Four, PA
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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.
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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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Joined: Aug 2003
Posts: 43,285 Bend,OR USA
Cab_Burge
I Win
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I Win
Joined: Aug 2003
Posts: 43,285
Bend,OR USA
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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)
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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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Joined: Oct 2004
Posts: 1,752 detroit area
moderncylinder
top fuel
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top fuel
Joined: Oct 2004
Posts: 1,752
detroit area
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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
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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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Anonymous
Unregistered
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Anonymous
Unregistered
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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.
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Re: Hemi problems again.. valve to valve clearance
[Re: moderncylinder]
#585934
01/18/10 10:53 PM
01/18/10 10:53 PM
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Joined: Jan 2003
Posts: 3,505 DFW
mr_340
master
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master
Joined: Jan 2003
Posts: 3,505
DFW
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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
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Re: Hemi problems again.. valve to valve clearance
[Re: moderncylinder]
#585936
01/19/10 04:17 PM
01/19/10 04:17 PM
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Joined: Dec 2005
Posts: 4,254 State of Fascism
52savoy
master
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master
Joined: Dec 2005
Posts: 4,254
State of Fascism
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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
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Re: Hemi problems again.. valve to valve clearance
[Re: 52savoy]
#585938
01/19/10 08:23 PM
01/19/10 08:23 PM
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Joined: Nov 2003
Posts: 6,293 Rock Springs
Bob_Coomer
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Joined: Nov 2003
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Rock Springs
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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]
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Re: Hemi problems again.. valve to valve clearance
[Re: Bob_Coomer]
#585939
01/19/10 09:47 PM
01/19/10 09:47 PM
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Joined: Aug 2009
Posts: 2,051 Mooresburg, Tn
'72CudaRacer
top fuel
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top fuel
Joined: Aug 2009
Posts: 2,051
Mooresburg, Tn
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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
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Re: Hemi problems again.. valve to valve clearance
[Re: Bob_Coomer]
#585940
01/20/10 11:14 AM
01/20/10 11:14 AM
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Joined: Dec 2005
Posts: 4,254 State of Fascism
52savoy
master
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master
Joined: Dec 2005
Posts: 4,254
State of Fascism
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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).
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Re: Hemi problems again.. valve to valve clearance
[Re: Bob_Coomer]
#585941
01/20/10 11:54 AM
01/20/10 11:54 AM
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Joined: Jun 2009
Posts: 705 Michigan
Hemiroid
super stock
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super stock
Joined: Jun 2009
Posts: 705
Michigan
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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
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Re: Hemi problems again.. valve to valve clearance
[Re: Bob_Coomer]
#585944
01/20/10 03:37 PM
01/20/10 03:37 PM
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Joined: Dec 2005
Posts: 4,254 State of Fascism
52savoy
master
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master
Joined: Dec 2005
Posts: 4,254
State of Fascism
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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
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Post deleted by Defbob
[Re: 52savoy]
#585946
01/20/10 11:24 PM
01/20/10 11:24 PM
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Anonymous
Unregistered
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Anonymous
Unregistered
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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
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Joined: Mar 2006
Posts: 9,910 Eighty Four, PA
B G Racing
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master
Joined: Mar 2006
Posts: 9,910
Eighty Four, PA
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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"?
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