Lifter Valley Screen Kits??
#41
Charter Member #601
Charter Member
Thread Starter
Ben,
I can see your point.. my Merlin block is 11.665" deck, but the cam is also raised .400". The part I dont get is the engine ran fine for 70hrs with the Schubeck lifters. The cam was in beautiful shape. The reason I changed out the Schubecks, was because I found two that were cracked and the crack started at the edge of a machined slot that had a sharp edge on it. Both cracked at the same spot. Now the wheels on those lifters was ceramic and if I had pounding on the lobes, I would think I would have shattered a wheel, or seen some damage to the cam. So in my opinon, the valve train was stable with the Schubecks, but not with the Isky's. The fact that the Isky's were much heavier, is what I suspect was the change that caused the problem. Now I was also running T&D Shaft rockers, had bushed lifter bores by LSM. All I changed was the lifters and a touch shorter push rod.
Now my problem might not have been an oiling issue, but if the spray bar reduces temps on lifter wheels, etc.. It might be of help, I dont know. If I reassemble this engine, I think I would add one, just to see if it helps. I guess I would know in 15hrs or so, then time for a rebuild..
bob, I see what you mean, I cant compare my setup to yours with the Big Chief heads.. whole different animal.. Thanks for the info though.
Learning a lot here. Love this kind of disscusion. Thanks to everyone.. keep it going, please.
I can see your point.. my Merlin block is 11.665" deck, but the cam is also raised .400". The part I dont get is the engine ran fine for 70hrs with the Schubeck lifters. The cam was in beautiful shape. The reason I changed out the Schubecks, was because I found two that were cracked and the crack started at the edge of a machined slot that had a sharp edge on it. Both cracked at the same spot. Now the wheels on those lifters was ceramic and if I had pounding on the lobes, I would think I would have shattered a wheel, or seen some damage to the cam. So in my opinon, the valve train was stable with the Schubecks, but not with the Isky's. The fact that the Isky's were much heavier, is what I suspect was the change that caused the problem. Now I was also running T&D Shaft rockers, had bushed lifter bores by LSM. All I changed was the lifters and a touch shorter push rod.
Now my problem might not have been an oiling issue, but if the spray bar reduces temps on lifter wheels, etc.. It might be of help, I dont know. If I reassemble this engine, I think I would add one, just to see if it helps. I guess I would know in 15hrs or so, then time for a rebuild..
bob, I see what you mean, I cant compare my setup to yours with the Big Chief heads.. whole different animal.. Thanks for the info though.
Learning a lot here. Love this kind of disscusion. Thanks to everyone.. keep it going, please.
#42
Charter Member #40
Charter Member
Dick, the cam I used in the Big Chiefs that worked was a Crower cam, 420 lobe, .714 at valve lift, 294/302 adv duration, at first used Isky Golds at 240# at 2.050"/490# at nose and then went to the 9385+ in at 2.100" with around 235# at seat and 575# at nose. Later I went to an even milder ramp according to Crower. Not a bunch different than your specs?? I do keep my lash tight, and like CCando, have bushed lifter bores, Jesel belt, spring spray bars etc.. I had heard the Schubeck was a good idea except when the lobe cracked and came apart you would be in for a world of hurt. Sounds like you were fortunate there and didn't go down that road!
#44
Platinum Member
Platinum Member
Bob,
All the the Crower lifters in the one engine were from an early 2007 batch. The other engine showed no lifter wear. Dave Crower admitted at the 2007 PRI Show that they had a problem with the roller needle bearings. He said he gave direction to his staff to notify the customers of a "recall"....they didn't and MRE was a direct Crower customer. Crower knew of the problem in January an we destroyed an engine in September. This ending up being an $18,000 problem.
When it was over, Dave reneged on his commitment to "help" given at the PRI Show, ending up paying more $ and lost a customer. I was so angry with his behavior, we risked $6,000 to collect $12,000.
If you want a spare set of Crower .937 lifters, they are "tested" with only 12 hrs!...I am done with Crower.
Many/most in the HP industry are bully's and assume the customer will do nothing. It did help my attitude some to give them a haircut.
All the the Crower lifters in the one engine were from an early 2007 batch. The other engine showed no lifter wear. Dave Crower admitted at the 2007 PRI Show that they had a problem with the roller needle bearings. He said he gave direction to his staff to notify the customers of a "recall"....they didn't and MRE was a direct Crower customer. Crower knew of the problem in January an we destroyed an engine in September. This ending up being an $18,000 problem.
When it was over, Dave reneged on his commitment to "help" given at the PRI Show, ending up paying more $ and lost a customer. I was so angry with his behavior, we risked $6,000 to collect $12,000.
If you want a spare set of Crower .937 lifters, they are "tested" with only 12 hrs!...I am done with Crower.
Many/most in the HP industry are bully's and assume the customer will do nothing. It did help my attitude some to give them a haircut.
#45
Charter Member #601
Charter Member
Thread Starter
bob,
You are right, I was lucky I never had one of the wheels break, and I was fortunate to find the cracks in the two bodies that I did. But the fact remains, the Schubecks lasted 70hrs, no cam or wheel damage. The Isky's lasted 20hrs and 5 of the lifters and lobes were eaten up. And there wasnt that much difference in setup between the two. Different lifter bushings, installed by the same company, .200" shorter push rods, same make, style, etc and the lifters.
Those are some serious heads on that motor.
Ben,
Love the haircut you gave them. Too bad it cost so much in grief..
You are right, I was lucky I never had one of the wheels break, and I was fortunate to find the cracks in the two bodies that I did. But the fact remains, the Schubecks lasted 70hrs, no cam or wheel damage. The Isky's lasted 20hrs and 5 of the lifters and lobes were eaten up. And there wasnt that much difference in setup between the two. Different lifter bushings, installed by the same company, .200" shorter push rods, same make, style, etc and the lifters.
Those are some serious heads on that motor.
Ben,
Love the haircut you gave them. Too bad it cost so much in grief..
#46
Banned
Join Date: Oct 2006
Location: Bradenton Florida
Posts: 5,927
Likes: 0
Received 0 Likes
on
0 Posts
Why are those rockers offset like that, just asking ,never seen that. Cool though.
Are those Jessel ? they kind of look like mine ,but mine are not offset.
Whats your spring press. again ?
And can to much spring press damage the cam , without destroyng the rollers ?
Are those Jessel ? they kind of look like mine ,but mine are not offset.
Whats your spring press. again ?
And can to much spring press damage the cam , without destroyng the rollers ?
#48
Banned
Join Date: Oct 2006
Location: Bradenton Florida
Posts: 5,927
Likes: 0
Received 0 Likes
on
0 Posts
Just talked to my engine builder,,,,,,he sayd , for a merlin block you need "tallbar lifters" ? or the cam will slam the rollers.
Also he sayd make shure that the oilrestrictors are out in the back of the block.
Those are the only 2 things he can think of, everything else ,,,,,,all the # you providet on cam spec and spring press. is fine.
Maybe you whant to check that ?!
PS.: he also said the spraybar will not resolve that problem you have.
Also he sayd make shure that the oilrestrictors are out in the back of the block.
Those are the only 2 things he can think of, everything else ,,,,,,all the # you providet on cam spec and spring press. is fine.
Maybe you whant to check that ?!
PS.: he also said the spraybar will not resolve that problem you have.
#49
Charter Member #601
Charter Member
Thread Starter
Ben,
LSM gets a pretty penny for their lifters.. they wouldnt tell me how long they would last. He said he as a boat running them, but would not guess as to how long they live. The way he said it was not very convincing.
I am attempting to sell this block, heads, intake combo and start over. I just dont want to pass on a problem to the next guy. Lunati had the idea of a long duration cam with .670" lift.. real easy ramps. I would think that would do it, with lighter springs, maybe. If someone wanted it, I would let it go. I think it would look very cool in a 55 chevy somewhere!
LSM gets a pretty penny for their lifters.. they wouldnt tell me how long they would last. He said he as a boat running them, but would not guess as to how long they live. The way he said it was not very convincing.
I am attempting to sell this block, heads, intake combo and start over. I just dont want to pass on a problem to the next guy. Lunati had the idea of a long duration cam with .670" lift.. real easy ramps. I would think that would do it, with lighter springs, maybe. If someone wanted it, I would let it go. I think it would look very cool in a 55 chevy somewhere!
#50
Charter Member #40
Charter Member
Daredevil, from what I know of the big chief head, the valves are angled at 14 deg., the intakes are equally spaced, the runners are more symetrical/equal length if you will rather than having a couple longer than the other two, the exhaust ports are what 2"+ higher than a stock config? These heads flow lots of air/fuel but like to be up over 6000 rpm or feed large displacement motors. Maybe someone that actually really knows this head will chime in.