Ram Jet ZL-1 lifter problems???
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Ram Jet ZL-1 lifter problems???
Has anyone heard of any problems with the stock GM solid roller lifters in the Ram Jet ZL-1 engines? A friend who has one said he had a lifter collapse while driving his car with the limited edition Ram Jet ZL-1 engine. First I've heard of this. Anyone else hear of such a problem?
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I'm referring to the Ram Jet ZL-1 454 limited edition engines......200 built. It uses a solid lift roller camshaft. Here's a link to it:
http://www.gmpartsdirect.com/results...umber=88961499
http://www.gmpartsdirect.com/results...umber=88961499
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Well, it's a solid roller lifter...they don't last forever. How many miles on it?
JIM
JIM
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Not sure.................he said it was within the first year he had the engine. He doesn't drive the car every day, so I'd guess under 5K miles, but that's strictly a guess. He said he was told that GM used low quality solid roller lifters, but I would "think" that on one of these limited edition engines, GM wouldn't want to risk bad pubicity by using low quality parts. But, again, that's a guess on my part.
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The 572's were using Crane stuff on cams and lifters...which was excellent. Not sure who did that cam though. It's a relatively high lift and short duration piece...which is tougher on parts.
Had he checked lash? Heard anything amiss? Did it die on intake or exhaust side?
For his next lifters tell him to get some that have pressurized oil to the rollers. Comp has them as well as Isky, Crower and Morel.
When you say collapse..you mean the roller wheel is all chewed up and gone? There's really nothing to collapse internally.
JIM
Had he checked lash? Heard anything amiss? Did it die on intake or exhaust side?
For his next lifters tell him to get some that have pressurized oil to the rollers. Comp has them as well as Isky, Crower and Morel.
When you say collapse..you mean the roller wheel is all chewed up and gone? There's really nothing to collapse internally.
JIM
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The 572's were using Crane stuff on cams and lifters...which was excellent. Not sure who did that cam though. It's a relatively high lift and short duration piece...which is tougher on parts.
Had he checked lash? Heard anything amiss? Did it die on intake or exhaust side?
For his next lifters tell him to get some that have pressurized oil to the rollers. Comp has them as well as Isky, Crower and Morel.
When you say collapse..you mean the roller wheel is all chewed up and gone? There's really nothing to collapse internally.
JIM
Had he checked lash? Heard anything amiss? Did it die on intake or exhaust side?
For his next lifters tell him to get some that have pressurized oil to the rollers. Comp has them as well as Isky, Crower and Morel.
When you say collapse..you mean the roller wheel is all chewed up and gone? There's really nothing to collapse internally.
JIM
Thanks,
Rex
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Did he stay solid roller? The Comps are good lifters..I have them in my 540.
Solid rollers require you to keep an eye on them. The performance comes with a little maintenance. Small blocks are a little easier due to lighter valvetrains, but BB's are tougher on things.
If he ever hears one tapping where it sounds a little unusual...he needs to check it immediately. NOT 50 miles down the road. They will quickly destroy stuff if one stops rolling or a rocker comes loose or whatever. Regularly checking the valves a couple of times a year allows you to keep an eye on things. The best practice is to pull the lifters and replace/rebuild them every year or two. Depends on miles and cam of course.
Hopefully he got a steel billet cam and not one of the austempered cast iron cores. If the part number ends with a -8...it's a cast iron one.
JIM
Solid rollers require you to keep an eye on them. The performance comes with a little maintenance. Small blocks are a little easier due to lighter valvetrains, but BB's are tougher on things.
If he ever hears one tapping where it sounds a little unusual...he needs to check it immediately. NOT 50 miles down the road. They will quickly destroy stuff if one stops rolling or a rocker comes loose or whatever. Regularly checking the valves a couple of times a year allows you to keep an eye on things. The best practice is to pull the lifters and replace/rebuild them every year or two. Depends on miles and cam of course.
Hopefully he got a steel billet cam and not one of the austempered cast iron cores. If the part number ends with a -8...it's a cast iron one.
JIM
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He put a Comp hyd roller in his engine and it sounds great, plus, he says it runs better than the GM solid roller. I too have one of these engines and even though mine has less than a hundred miles on it, his unfortunate incident has made me a little worried about mine. We both had our cars at a show yesterday..................it was neat to have 2 of the 200 limited edition Ram Jet ZL-1 engines there.
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He should be OK...just keep RPM down below 6500 rpm or so to be safe. Still ought to check and see what core that HR cam is made on and how much spring pressure.
That IS cool to have two of those engines side by side. How does the sound compare between the two? It would be interesting to hear exactly what cam he installed and what he likes better about it.
JIM
That IS cool to have two of those engines side by side. How does the sound compare between the two? It would be interesting to hear exactly what cam he installed and what he likes better about it.
JIM
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Since it used on the street and not the track, I would have used the flat tappet cam...Roller camshafts are good shafts but for a competition engine where ever its used needs a rev kit which is to keep the heavy lifters on the shaft...RPM protection so your not beating the rollers off the ramps of the cam...427, 454, or larger, it makes no difference....many get away with out the kit but the rollers come apart and can destroy parts in a hurry...A high maintenance engine that is better served with a solid lifter flat tappet cam and not the roller for the street....
You may not get bragging rights on a "roller", but there just as quick and last a lot longer and go farther between tear downs...I run my LS-7 and 88 almost exclusively on the street as the Detroit dragway is no longer available and as you know they are not roller engines but however are a couple of points higher in compression with bigger heads...
BTW, i put 28K street miles on the 88...worn and tired at that point it required almost everything but is alive again and probably better then it was new....There nice engines as many here already know..
Otherwise, if you insist on the roller, schedule tear downs in your appointment book to make sure it stays together...
You may not get bragging rights on a "roller", but there just as quick and last a lot longer and go farther between tear downs...I run my LS-7 and 88 almost exclusively on the street as the Detroit dragway is no longer available and as you know they are not roller engines but however are a couple of points higher in compression with bigger heads...
BTW, i put 28K street miles on the 88...worn and tired at that point it required almost everything but is alive again and probably better then it was new....There nice engines as many here already know..
Otherwise, if you insist on the roller, schedule tear downs in your appointment book to make sure it stays together...
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
On a new motor with solid roller cam the you have to keep an eye on them. THese are not plug and play motor for guys that don't want to take the intake off every year to check everthing and the valve covers shoud come off ever few thousand to check lash to make sure nothing is going south. If you are not willing to do this then there are alternatives 
BTW which comes first, the big hood or the big air cleaner ?
BTW which comes first, the big hood or the big air cleaner ?
