[Half-Inch Stud]

Just throwing out the idea of a Roller Lifter Development for the OHC-6.

The technical case:
The cam Lobe slides across a stationary metal follower, and results in lobe wear. IF the Follower has a Roller, like the Modern valvetrains then cam (and engine) Reliability/life can be greatly improved. <-- well known.

The Biz case: (Market Analysis)
The Roller cam follower can be Similar-to, made from established Roller parts.
Only Custom part would be the Follower forging (or casting).
Some assembly required. (rebuildable).

Alternate: is there a modern follower (Lincoln 4.6L V8?) that can be adapted to the OHC-6?

Thoughts?

[TheSilverBuick]

I was looking at the Ford Cammer engine set up, as a guide since they are rollers, but the design is quite a bit different than the Pontiac's =/ On the same token, if you go roller, can a design be made to get more than 1.3 rocker ratio?

I was wondering how hard it would be for a machinist, or CNC'ist, to notch the top of a follower, about 1/4"(?) and drop a cylinder/small rod in it and with the oil hole on the cam lobe see if it got sufficient lubrication to "roll" inside the notch.

[Half-Inch Stud]

No real oil film float occurs. Steel-to-steel Wiping motion remain.

My thoughts remain on having a roller be the Lobe contact.

Only other opportunity is the desmo-dromic approach on the OHC-6. That would be "easy": A cam full of off-center rounds with 1-piece followers hung like shower rings. DANG! it would be super!

[boater bill]

Aren't there roller follers for a Ford Pinto 4 cylinder available?
IIRC they have a very similar follower size and shape.

[Cammer-6]

Ive done quite a bit of investigation on this years ago
heres a pic of the ford follower,OHC-6 follower and a roller lifter from a Detroit that could be used for a roller donor.
The specs are
Detroit roller .90 diameter,.55 wide
Ford roller .90 diameter,.50 wide
OHC-6 pad width .90 wide

the fulcrum point of the Ford is too short,only cure is to offset bush the lash adjuster hole in the OHC-6 head,install smaller diameter lash adjuster.
it will need a billet or forged cam.
Other ideas were tossed out there as using a hex shaft and keyed lobes and spacers
to make a modular cam
The GM OHC-6 4.2(TrailBlazer) used much smaller lash adjusters and cam retard.

[Half-Inch Stud]

Post #5 excellent: so it is a simple matter of having 1 custom cast/forged/billlt part machined. Throw the Roller, pin, needles in a bag and sell the kit as "some assembly required".

[Cammer-6]

OEM as cast cam is not compatible with a roller
at least from what I was told by Crane years ago.

[TheSilverBuick]

I can see why a conventional in block cam can't have roller lifters put on it because the cam lobes are ground with an angle to make the lifters spin and that would be bad for a roller lifter that wants a flat surface. But on these OHC setups, where the cam has to be square with the follower, I don't see why a roller wouldn't work on a standard regular ol' cam. What I'd really like to see as I mention above, is to see if a larger rocker ratio could be gained with out comprimising the contact with the valve stem.

[Jack Gifford]

Cammer-6: Is that pictured roller follower a Ford piece or an aftermarket item? The Esslinger 2.3L followers look quite different from that, as I recall.

In your "investigation" did you come across any full-roller followers? That is, rollers both at the cam and at the valve stem.

Half-inch: Why do you talk about desmodromic valve actuation and eccentric-circle cams in the same breath?

[Cammer-6]

Originally Posted by pontiac jack

Cammer-6: Is that pictured roller follower a Ford piece or an aftermarket item? The Esslinger 2.3L followers look quite different from that, as I recall.

In your "investigation" did you come across any full-roller followers? That is, rollers both at the cam and at the valve stem.

Half-inch: Why do you talk about desmodromic valve actuation and eccentric-circle cams in the same breath?

ford piece FIZZ-6564-A
never checked the full roller
got an ideas?

[Jack Gifford]

My "idea" concerns full-roller followers to use in building a DOHC hemi head (4-cyl). I've yet to find any to even consider using, so I might need to manufacture eight of them myself.

[Cammer-6]

is it really worth the effort to make a full roller?
you can use a lash cap on valve tip if your worried about wear.
keep us posted on what you come up with

[Jack Gifford]

Originally Posted by Cammer-6

is it really worth the effort...

I don't know that it's necessary, but it's very desirable to minimize side thrust on valves of what I consider an "extreme" engine. I'll be shooting for 4 HP/c.i. (blown alky); the simulations show that power will peak at 9,500 - 10,500 RPM. And it will need to run in that rev range for longer duration than a dragrace engine (land-speed racer).

[Half-Inch Stud]

Uhm, forgetabout the Valve-stem-tips. only OHC-6 concern are the cam lobes.

Consider Pseudo-Desmo-Dromic: Round Cam Lobes, off-center for lift.

The tough part: Cast Aluminum Follower has "Shower curtain ring" feature with Press-in sleeve bearing, Sliding(translating) is needed so ring would have a "flat" that slides along a Cast follower featuring a flat surface for ring slide. Not really DESMO-DROMIC but close.

Finally Cam's oiling system drilled to pressurize each ring (or HYD lash pumps).
Some cam tower assembly required. Imagine that. HIS
========================================
To be fully Desmo-dromic; No valve springs on Intake Valve, Hinged Follower.
Follower links to Ring with a single "chain link" on steroids.
Some impossible assembly required, so Cam tower may need to be a split block to allow 2-piece Cam-rings to be assembled like Rod-caps.

[TheSilverBuick]

Originally Posted by pontiac jack

I don't know that it's necessary, but it's very desirable to minimize side thrust on valves of what I consider an "extreme" engine. I'll be shooting for 4 HP/c.i. (blown alky); the simulations show that power will peak at 9,500 - 10,500 RPM. And it will need to run in that rev range for longer duration than a dragrace engine (land-speed racer).

Interesting. My plan is to clean up and mildly port the head, then cram as much boost with a turbo into the engine as possible. Using sequential EFI to balance the afr's in each cylinder and likely second stage methanol injection for detonation. I'm shooting first for 600Hp, but might try and see how far I can take the boost if I put good rods in the bottom end.

This will be street car that occassionally see's the strip, though if I can get at least 800HP out of it, I'll take it on Drag Week in the small block power adder class. (anyone here seen Huber and his 2.3L mustang?).

[Cammer-6]

may want to girdle the bottom end like the factory intended to do
and use a short throw crank(230).

Tom Langdon made some fixed lash adjusters to help with the hydraulics pump up issues.
This can be partially cured by using a needle valve and pressure regulator to control lash adjuster oil feed.

[Goatracer1]

The Mopar 2.2L and 2.5L four cyl.s used a hydraulic lash adjuster and a roller cam follower that was quite simple.

[Half-Inch Stud]

JUST occurred to me:

OHC-6 Cam lobes are so large(wide), that we ought consider putting the Roller into the Lobe. Stock Followers etc. Only difference would be the camshaft.

WHO's gonna do it?
======================================
Otherwise what'sa matter with the Roller Follower in Post#5?

[Cammer-6]

Originally Posted by Half-Inch Stud

JUST occurred to me:

OHC-6 Cam lobes are so large(wide), that we ought consider putting the Roller into the Lobe. Stock Followers etc. Only difference would be the camshaft.

WHO's gonna do it?
======================================
Otherwise what'sa matter with the Roller Follower in Post#5?

explain please
is it the paint fumes?

[Half-Inch Stud]

Originally Posted by Cammer-6

explain please is it the paint fumes?

No, it's the boredom. See the best approach is to have a Roller-Follower put into the OHC-6 camtrain (that assumes the fells has a good cam and desired durations). So still need a new cam with good lobe profiles.

Roller-cam Lobes would TRY to take advantage of all the spent cam cores with un-interesting Durations& lift. 12 roller lobes, with cam duration set by the Roller locations, would likely slap the followers, butt hey, an intentional design effort may get the Roller to meet the Follower just fine. Lobe basecircles don't wear like the Lobe, so the sliding Basecircle with roller lobe ought to be reliable, but potentially goofy.

Desmo-dromic is lost in the paint fumes.