solid lifters on hydraulic cams??
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solid lifters on hydraulic cams??
Now I know this has been done to death.. but can solids work on a hydro cam and hydro's on a solid cam not??
I thought tha the hydro cams had a slightly faster ramp...... as there is "give" in the hydro lifter....
I thought tha the hydro cams had a slightly faster ramp...... as there is "give" in the hydro lifter....
- Piledriver
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Hydros could be used on a solid cam.
Not a good idea from a performance standpoint...
Solids should never be used on a hydro cam.
Likely to break things.
Not a good idea from a performance standpoint...
Solids should never be used on a hydro cam.
Likely to break things.
Addendum to Newtons first law:
zero vehicles on jackstands, square gets a fresh 090 and 1911, cabby gets a blower.
EZ3.6 Vanagon after that.(mounted, needs everything finished) then Creamsicle.
zero vehicles on jackstands, square gets a fresh 090 and 1911, cabby gets a blower.
EZ3.6 Vanagon after that.(mounted, needs everything finished) then Creamsicle.
- Piledriver
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Hydro cams have ~no ramps, the slop is taken up in the lifters.
With no ramps to gently take up the lash and get things started, opening the valves would be closer to opening them with a hammer. (Much more violent in any case)
Theh cam/lifters themselves might tolerate it for awhile, but something is likely to give after awhile.
With no ramps to gently take up the lash and get things started, opening the valves would be closer to opening them with a hammer. (Much more violent in any case)
Theh cam/lifters themselves might tolerate it for awhile, but something is likely to give after awhile.
Addendum to Newtons first law:
zero vehicles on jackstands, square gets a fresh 090 and 1911, cabby gets a blower.
EZ3.6 Vanagon after that.(mounted, needs everything finished) then Creamsicle.
zero vehicles on jackstands, square gets a fresh 090 and 1911, cabby gets a blower.
EZ3.6 Vanagon after that.(mounted, needs everything finished) then Creamsicle.
- Piledriver
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I think he needs more coffee, and to think about it.51MAN wrote:Well a UK engine biulder has catagoricaly stated that he knows best (I wont go into details... PM me if you really must know ). that you can use solids on hyrdo cam but not hydros a solid cam...
Theh laws of physics are against him.
(or he just got it backwards in a post, happens, brain<>finger disconnect)
Addendum to Newtons first law:
zero vehicles on jackstands, square gets a fresh 090 and 1911, cabby gets a blower.
EZ3.6 Vanagon after that.(mounted, needs everything finished) then Creamsicle.
zero vehicles on jackstands, square gets a fresh 090 and 1911, cabby gets a blower.
EZ3.6 Vanagon after that.(mounted, needs everything finished) then Creamsicle.
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No, really, Greg, I do think you have it the wrong way 'round. It's the hydro cams that have slower initial ramping to create the inertial reaction that opens the ball valve inside the lifter so it can admit a little oil before it gets loaded by the valve spring. Solid cams have quicker ramps. If you want to see the difference, take a look at the duration specs for hydro vs. solid cams; the difference in degrees between lift at fifty and advertised is a lot more on a hydro, typically about 45-70 on a hydro vs. 30-40 for a solid cam.
This has come up before but I've always figured you could run solid lifters on a hydro cam if you wanted to, but not vice versa. The solid lifter will like a slow ramp as well as a fast one, it might even wear more slowly, but a hydro has to have that ramp timing to adjust itself.
Hey while we're on the subject, I don't know if you guys noticed that Elgin has hydro T1 cams:
http://www.elgincams.com/c-vw2.html (I think his are regrinds, not sure)
and Engle also has them in their new catalog, under VW:HIGHLIFT 1.4-1.5 Rockers:
http://www.elgincams.com/c-vw2.html
Some interesting offerings. I'm itchin' to try one out from one of them.
This has come up before but I've always figured you could run solid lifters on a hydro cam if you wanted to, but not vice versa. The solid lifter will like a slow ramp as well as a fast one, it might even wear more slowly, but a hydro has to have that ramp timing to adjust itself.
Hey while we're on the subject, I don't know if you guys noticed that Elgin has hydro T1 cams:
http://www.elgincams.com/c-vw2.html (I think his are regrinds, not sure)
and Engle also has them in their new catalog, under VW:HIGHLIFT 1.4-1.5 Rockers:
http://www.elgincams.com/c-vw2.html
Some interesting offerings. I'm itchin' to try one out from one of them.
- Piledriver
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Thanks for the kind way you put that, but not the slightest doubt in my mind I am correct, I even did some Googling for you...
The reason hydros check so much longer is because... they have to be... to be the same effective duration at the valve.
Solids have GRADUAL ramps to take up the lash smoothly.
Hydros have practically NO ramps, likely so as to operate said little ball valve properly.
This is also why using hydros on a SOLID cam is a bad idea, but it won't lead to rapid destruction, just a possible case of runs-like-ass. (Unless set to almost full compression, which actually could be argued to be a feature in several ways, pushrod cup higher/lighter pushrod, and oil is lighter than steel... hmmm)
Every camshaft manufacturer on the planet will tell you the same, and typically has dire warnings to that effect.
Google for yourself, here's some reading to start with.
http://books.google.com/books?id=1ypb-B ... &ct=result
The reason hydros check so much longer is because... they have to be... to be the same effective duration at the valve.
Solids have GRADUAL ramps to take up the lash smoothly.
Hydros have practically NO ramps, likely so as to operate said little ball valve properly.
This is also why using hydros on a SOLID cam is a bad idea, but it won't lead to rapid destruction, just a possible case of runs-like-ass. (Unless set to almost full compression, which actually could be argued to be a feature in several ways, pushrod cup higher/lighter pushrod, and oil is lighter than steel... hmmm)
Every camshaft manufacturer on the planet will tell you the same, and typically has dire warnings to that effect.
Google for yourself, here's some reading to start with.
http://books.google.com/books?id=1ypb-B ... &ct=result
Addendum to Newtons first law:
zero vehicles on jackstands, square gets a fresh 090 and 1911, cabby gets a blower.
EZ3.6 Vanagon after that.(mounted, needs everything finished) then Creamsicle.
zero vehicles on jackstands, square gets a fresh 090 and 1911, cabby gets a blower.
EZ3.6 Vanagon after that.(mounted, needs everything finished) then Creamsicle.
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- Joined: Thu Nov 22, 2001 12:01 am
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Cheers Chris
Waded through that book info Piledriver... seems to contradict its self ... unless I read it wrong..
Let me try and see if I can explain how I understand the difference..
a cam for a hydro has a "kick" on the initial opening, to take up the "slack" in the lifter (the oil essentially acts as a damper as the ball shuts off etc so negating the "hammer")
if hydro lifters run on a solid cam this means it takes a lot longer to get the ball shut off and the damping effect isnt present really.. the valve doesnt open as far as quickly..
If solids are run on a hydro cam, then the "kick" at the start is effectively taking up the "clearance's" in lifter/pushrod/rocker/valve tip instantly.. like said "hitting with a hammer". where the solid cam would start off gently and accelerate fast when its got the valve train moving...
Does that make sense? or have I got it wrong? That wuld make a lot of sense with the 50thou lift degrees starting earlier... but I still dont get the "advertised and actual".. but thats another story
Waded through that book info Piledriver... seems to contradict its self ... unless I read it wrong..
Let me try and see if I can explain how I understand the difference..
a cam for a hydro has a "kick" on the initial opening, to take up the "slack" in the lifter (the oil essentially acts as a damper as the ball shuts off etc so negating the "hammer")
if hydro lifters run on a solid cam this means it takes a lot longer to get the ball shut off and the damping effect isnt present really.. the valve doesnt open as far as quickly..
If solids are run on a hydro cam, then the "kick" at the start is effectively taking up the "clearance's" in lifter/pushrod/rocker/valve tip instantly.. like said "hitting with a hammer". where the solid cam would start off gently and accelerate fast when its got the valve train moving...
Does that make sense? or have I got it wrong? That wuld make a lot of sense with the 50thou lift degrees starting earlier... but I still dont get the "advertised and actual".. but thats another story
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The engine man, he says this...
I'll tell you what I think too.. I've never got hydraulics to run on a solid cam but have seen loads of solids running on hydraulics withy no probs.
If you're serious about runnng 1.4:1 rockers, watch the cleacance of the push rod to the tube and make sure you have .090" possible further movement with the valve fully down. You'll be hittin the top of the guide.
I suggest solids, preferable second hand on an old cam with 1.25 rockers.
You'll also need type 1 13/15/1600 push rods. Old stock only, the new 'pattern' ones are crap.
If you use the rockers with the adjuster at the bottom, use lash caps or they'll wipe your valve tops out in time.
I'll tell you what I think too.. I've never got hydraulics to run on a solid cam but have seen loads of solids running on hydraulics withy no probs.
If you're serious about runnng 1.4:1 rockers, watch the cleacance of the push rod to the tube and make sure you have .090" possible further movement with the valve fully down. You'll be hittin the top of the guide.
I suggest solids, preferable second hand on an old cam with 1.25 rockers.
You'll also need type 1 13/15/1600 push rods. Old stock only, the new 'pattern' ones are crap.
If you use the rockers with the adjuster at the bottom, use lash caps or they'll wipe your valve tops out in time.
- fastback
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when a hydro lifter is fully pumped up. it act's as a mechanical right?
since fluid can not be compressed( basic of hydraulic systems)
and the theory about solid lifters on hydrocam not working sounds strange to me. Slow ramps, low lift and in my case much lighter lifters , should be good for any cam.??
I'll post some update on my combo CB hydrocam 2254 on scat lube-a-lobes.i will tare down my engine in fall/vinter.
since fluid can not be compressed( basic of hydraulic systems)
and the theory about solid lifters on hydrocam not working sounds strange to me. Slow ramps, low lift and in my case much lighter lifters , should be good for any cam.??
I'll post some update on my combo CB hydrocam 2254 on scat lube-a-lobes.i will tare down my engine in fall/vinter.
Last edited by fastback on Sun Jun 29, 2008 1:44 pm, edited 1 time in total.