Hydraulic Cam // Solid Lifters

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Saltcityslant

Saltcityslant

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Me again,

Hi,

I built a slant 6, 225. I bought a comp cam, which came with new hydraulic lifters, as it's a hydraulic cam. The rebuild kit I bought came with new solid lifters, and as this is a budget build, I installed the new solid lifters with the hydraulic cam. I understand that the "ramp" on the hydraulic cams can be steeper as they live with zero lash, but I don't have a hydraulic style/pushrod lubricating valve train, that's not how my year of slant was built. I don't want to buy that other head, though, because it's not really a requirement of the build.

Question is, if I run tight enough lash, but loose enough it's not constant contact, and check after the first heat cycle, will this work out alright? It's not a super aggressive cam, it lifts at .440 while the factory lifts at .405. I've lashed the engine at .006 intake and .009 exhaust. I've lubed the whole system with Moly prelube, and I plan to pre-pressurize the oil system with comp break in oil before I actually do my cam break in procedure.

Feeling paranoid, but super thorough. I didn't degree the motor when assembled but I did double check tdc and valve closure as cams can be incorrectly stamped. I need advice from guys that have mixed these before, I've built engines myself, but this is a bit of an experiment. I am pretty stoked that it'll be stable at high rpms as I balanced the crank and all the rods. The hydraulic system has a tendency to float, so I'm hoping this thing rips. (In my light *** truck)
 
Saltcityslant said:
Me again,

Hi,

I built a slant 6, 225. I bought a comp cam, which came with new hydraulic lifters, as it's a hydraulic cam. The rebuild kit I bought came with new solid lifters, and as this is a budget build, I installed the new solid lifters with the hydraulic cam. I understand that the "ramp" on the hydraulic cams can be steeper as they live with zero lash, but I don't have a hydraulic style/pushrod lubricating valve train, that's not how my year of slant was built. I don't want to buy that other head, though, because it's not really a requirement of the build.

Question is, if I run tight enough lash, but loose enough it's not constant contact, and check after the first heat cycle, will this work out alright? It's not a super aggressive cam, it lifts at .440 while the factory lifts at .405. I've lashed the engine at .006 intake and .009 exhaust. I've lubed the whole system with Moly prelube, and I plan to pre-pressurize the oil system with comp break in oil before I actually do my cam break in procedure.

Feeling paranoid, but super thorough. I didn't degree the motor when assembled but I did double check tdc and valve closure as cams can be incorrectly stamped. I need advice from guys that have mixed these before, I've built engines myself, but this is a bit of an experiment. I am pretty stoked that it'll be stable at high rpms as I balanced the crank and all the rods. The hydraulic system has a tendency to float, so I'm hoping this thing rips. (In my light *** truck)
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Shane did that, documented tight-lashing solids on His hydraulic, His Member Name is @dart19666.....hasn't been on here for a good while.
More importantly, the quality/accuracy of new lifter faces has been poor, having them checked/corrected is recommended.
 
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Rollers yes. Flat tappet no. I’ve never seen it successfully done with flat tappets. Doesn’t mean it can’t, it just means I’ve seen em fail. I’d personally lash em tighter than that though, I’d only leave enough lash so that when the engine is up to operating temp the lash is damn near zero. Come to think of it, what I’d do is buy the correct camshaft.
 
Many folks, including myself, have run solid lifters on hyd cams, flat tappet & roller, & have had zero problems. The Comp Cams Max Area lobes are designed for use with sol or hyd lifters. I would ensure the lash [ hot ] is 0.006" for int & exh.
 
I wouldn't do it on a slant 6. They oil differently than a conventional engine. I'd run hydraulic lifters on the hydraulic cam, or get a solid cam and run solid lifters. Either way though, I'd have the new lifters resurfaced by a competent machine shop.
 

RustyRatRod said:
I wouldn't do it on a slant 6. They oil differently than a conventional engine. I'd run hydraulic lifters on the hydraulic cam, or get a solid cam and run solid lifters. Either way though, I'd have the new lifters resurfaced by a competent machine shop.
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Thanks for the advice, the solid lifters that I have were resurfaced. I got them through the machine shop in a kit and had them do it. Had trouble with solid lifters on a Toyota a few years back.
 
Bewy said:
Many folks, including myself, have run solid lifters on hyd cams, flat tappet & roller, & have had zero problems. The Comp Cams Max Area lobes are designed for use with sol or hyd lifters. I would ensure the lash [ hot ] is 0.006" for int & exh.
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Thanks for the advice. It's sounding like it's at my own peril, could work, won't if I'm not meticulous and careful.

I had the cam in the first place from a friend, even though it's not the right solid cam for this engine. That's where the issue starts from, I can't decide between sending it, and redoing the motor, sinking a thousand more into it. I figured it would be totally fine, but the more reading I do, the more paranoid I become.
 
Killer6 said:
Shane did that, documented tight-lashing solids on His hydraulic, His Member Name is @dart19666.....hasn't been on here for a good while.
More importantly, the quality/accuracy of new lifter faces has been poor, having them checked/corrected is recommended.
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I couldn't find that thread, but I looked. Seems pretty split, it's not super wise but not impossible? I just need to decide what I'm going to do. I just feel like it's pretty unlikely I'll be able to get someone to buy this cam off me, or sink another grand into the motor (which isn't really high power anyway) which makes me want to send it. But I also don't want catastrophic engine failure, because main and rod bearings are expensive which makes me not want to do it.

Decisions decisions
 
Saltcityslant said:
I couldn't find that thread, but I looked. Seems pretty split, it's not super wise but not impossible? I just need to decide what I'm going to do. I just feel like it's pretty unlikely I'll be able to get someone to buy this cam off me, or sink another grand into the motor (which isn't really high power anyway) which makes me want to send it. But I also don't want catastrophic engine failure, because main and rod bearings are expensive which makes me not want to do it.

Decisions decisions
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He has a YT Channel, I think it's Slant Garage Daily, or Slant Daily Garage or similar.....it would've been linked in one of His last posts on here.
 
Saltcityslant said:
Had a hard time finding those components for this. It's an early year slant, but I am not sure exactly what year.
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Doesn't make any differance on the year of the head. The only difference is the rear rocker shaft mounting bolt. Use the correct bolt for the head. Make sure you use the hydro shaft. It is different from the solid shaft.
PS: You also need the matching pushrods
 
Saltcityslant said:
I built a slant 6, 225. I bought a comp cam
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That often doesn't work out as well as the buyer would like to hope. There are widely-known sources for better (and less expensive) Slant-6 camshafts.

Saltcityslant said:
came with new hydraulic lifters, as it's a hydraulic cam. The rebuild kit I bought came with new solid lifters, and as this is a budget build, I installed the new solid lifters
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That was the wrong thing to do.

Saltcityslant said:
I don't have a hydraulic style/pushrod lubricating valve train, that's not how my year of slant was built. I don't want to buy that other head
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You don't need to replace the cylinder head to run hydro lifters on a Slant-6 originally built with solid lifters. The hydro-lifter components (pushrods, rockers…) can be directly installed on any Slant-6 head. Then you just need to make sure you've got adequate oil to the top end – the hydro-lifter setup needs more oil than the solid setup, so the rearmost cam journal should be 360° grooved to supply it. If it is not, that's a Comp Cams fuсkup.

Saltcityslant said:
Feeling paranoid
Click to expand...

That's the voice you should listen to, telling you you've made a mistake that needs fixed.

Saltcityslant said:
but super thorough. I didn't degree the motor when assembled
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These two things can't both be true at the same time. And using the wrong kind of camshaft for the rest of the valvetrain (or vice versa) also can't be counted as thorough.

Saltcityslant said:
this is a bit of an experiment.
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So is using Cheez-Whiz instead of frosting on a chocolate cake. In both cases, a negative outcome can be dependably predicted.

Saltcityslant said:
The hydraulic system has a tendency to float
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{{citation needed}}
 
slantsixdan said:
That often doesn't work out as well as the buyer would like to hope. There are widely-known sources for better (and less expensive) Slant-6 camshafts.



That was the wrong thing to do.



You don't need to replace the cylinder head to run hydro lifters on a Slant-6 originally built with solid lifters. The hydro-lifter components (pushrods, rockers…) can be directly installed on any Slant-6 head. Then you just need to make sure you've got adequate oil to the top end – the hydro-lifter setup needs more oil than the solid setup, so the rearmost cam journal should be 360° grooved to supply it. If it is not, that's a Comp Cams fuсkup.



That's the voice you should listen to, telling you you've made a mistake that needs fixed.



These two things can't both be true at the same time. And using the wrong kind of camshaft for the rest of the valvetrain (or vice versa) also can't be counted as thorough.



So is using Cheez-Whiz instead of frosting on a chocolate cake. In both cases, a negative outcome can be dependably predicted.



{{citation needed}}
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Got smoked...

Sucks to have fucked up, but I'd rather it work. Thanks for the input, Dan.
Since I don't have to replace the entire cylinder head, from the posts above I need to 1. Use the new hydrualic lifters that I have; swap to oiling pushrods, rockers, and a rocker shaft, with the rear oiling bolt. Do I have that correct? Should be able to do it without pulling the head off.

Rusty, it's not that I want to do it wrong, it's that it sucks that I have to spend a bunch of money and go backwards. If that's what needs to be done I'll do it.

Dan, I checked photos that I have of the camshaft, and it does have the oil groove that goes all the way around. Fingers crossed they didn't send me trash, I guess?

To continue,

Push Rods: SBI 1901450 or 1901449 (7.500 or 9.985 respectively, not sure which is correct yet)

Rocker Arms: SBI 1801078 (right) & 1801077 (left)

Here's what I can find that's available new, which leaves just a hydraulic rocker shaft and the bolt with the oil galley. (I'm not treating this section as the "wanted" forum I'm just observing.)

Do I have this correct? Thanks again to everyone for all the criticism, only makes me and the build better in the long run.
 
Warning Will Robinson, warning. Not sure on the pushrods, as I would have to measure the correct length. The rocker arms listed are for a small block not a slant six. My sugeation would be to post a wanted ad on the site, looking for good used rocker arms, shaft, and pushrods for a 1981 and newer hydraulic slant six.
PS: use the rear rocker shaft bolt that is on your current valve train/head. In some applications it is necessary to enlarge (drill) the lower rear hole on the rocker shaft to be able to use the early head/bolt.
If you are getting confused, and want some clarification, send me a DM, and I will give you my phone number.
 
Charrlie_S said:
Warning Will Robinson, warning. Not sure on the pushrods, as I would have to measure the correct length. The rocker arms listed are for a small block not a slant six. My sugeation would be to post a wanted ad on the site, looking for good used rocker arms, shaft, and pushrods for a 1981 and newer hydraulic slant six.
PS: use the rear rocker shaft bolt that is on your current valve train/head. In some applications it is necessary to enlarge (drill) the lower rear hole on the rocker shaft to be able to use the early head/bolt.
If you are getting confused, and want some clarification, send me a DM, and I will give you my phone number.
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Warning Will Robinson... I had to look that up, before my time.

Sounds good. I'll post in wanted.
 
Saltcityslant said:
Warning Will Robinson... I had to look that up, before my time.

Sounds good. I'll post in wanted.
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Why not just get the correct solid cam for Your mill, & sell the Comp to somebody with a late model w/hydraulics, skip all the conversion/monkey-motions.
The money You're tossing out to convert isn't worth it IMO to have an inferior valvetrain system, put that $$$ into a Oregon Cam Grinders solid & roll..
 
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