Roller CAM -FE

[patrickt]

Originally Posted by decooney

What's amazing to me about this thread is many have been chatting right here on ClubCobra for at least eight to ten years solid back and forth (look back through threads) about FE hydraulic vs. solid lifter setups, related problems, advancements, here we are approaching 2010 and vendor-x now coming out with yet another new redesigned prototype roller lifter with oil hole/groove technology for FEs to try and get it to last a little longer and work better.

Remind me again why a roller is better than a solid, flat tappet cam?

[RICK LAKE]

patrickt it's about what kind of sex you want to have. Just like what camshaft and lifter you want to run in your motor. 8,000 rpms solids win out, street motor with a 6,200-6,500 limit making alot of torque, hydro rollers. If you have the money, Schubecks in aluminum and any size camshaft and spring combo you want. I believe a hydro roller with proper maintain ance will last 100K miles. In the old days a solid motor would last 70-80K miles with todays cheap metals, mileage is less, some because of the oil and lack of zinc and other needed sliding materials needed. What works for some doesn't work for others. You like solids and I see no problem. Only lash is your enemy and how much lash is in the valve train. Rick L.

[patrickt]

... the sound. Solids, be it flat or roller, just sound so much better than hydros. For a Cobra, you just gotta have that sound, IMHO. And adjusting the lash is really a joy. I can take all day adjusting valve lash (in fact, as slow as I work, it does take me all day to adjust 16 valves...).

[767Jockey]

Originally Posted by patrickt

... the sound. Solids, be it flat or roller, just sound so much better than hydros. For a Cobra, you just gotta have that sound, IMHO. And adjusting the lash is really a joy. I can take all day adjusting valve lash (in fact, as slow as I work, it does take me all day to adjust 16 valves...).

Patrick,
I can't agree with you more. To me, the sound of solid lifters tapping away in close knit syncopation is the soundtrack of my youth. It still gives me goosebumps when I hear a raucous idle and solids tapping in the back round. Certainly hydraulic rollers, for most FE's, make a lot more sense. However, to me a Cobra is not a car that makes a whole lot of sense, instead it's a visceral, joyful experience. This is the only reason my engine (if it ever runs) is equipped with a solid roller cam. I can't wait to hear it. Keith Craft, who speced out the whole engine and supplied all the technical parts, is predicting in excess of 625 HP and over 600 Ft. Lbs of torque. With that on tap, I can't wait to feel it, either!

[afret]

Patrick,
I can't agree with you more. To me, the sound of solid lifters tapping away in close knit syncopation is the soundtrack of my youth. It still gives me goosebumps when I hear a raucous idle and solids tapping in the back round. Certainly hydraulic rollers, for most FE's, make a lot more sense. However, to me a Cobra is not a car that makes a whole lot of sense, instead it's a visceral, joyful experience. This is the only reason my engine (if it ever runs) is equipped with a solid roller cam. I can't wait to hear it. Keith Craft, who speced out the whole engine and supplied all the technical parts, is predicting in excess of 625 HP and over 600 Ft. Lbs of torque. With that on tap, I can't wait to feel it, either!

If you don't mind me asking, what are specs on your solid roller and what springs are you going to run? Thanks!

[767Jockey]

Originally Posted by afret

If you don't mind me asking, what are specs on your solid roller and what springs are you going to run? Thanks!

Nah, I don't mind at all. The specs are 255/262 at .050 with .383 lobe lift and a 112 lobe separation. It will be installed at 4 degrees advanced at 108. This cam should give .674 lift on both the intake and the exhaust before lash with 1.76 rockers.
As far as springs, I don't know! I bought the Stage II heads from Keith, and he installed the proper matching springs on the heads with titanium retainers. I never did ask him for the spring specs. The cam, as you can see, is big enough to make lots of power, yet small enough to not be too difficult. Should be fun. The rest of the valve train and intake is a set of Harland Sharp roller rockers and stands, and a port matched Performer RPM with all the markings and logos ground off and bead blasted for a more original look, with a Quick Fuel 950 carb, all original gold color, with LeMans bowls. Should run good and look good too. If I can only get a darned block now......

[decooney]

Originally Posted by patrickt

Remind me again why a roller is better than a solid, flat tappet cam?

I can't provide first hand experience, as I still have a solid flat-tappet cam in my last three FEs in different cars, against my short block engine builder's 1st recommendations. However, I keep studying this topic along with all of you. If I do a future FE build with a different block, i'll be shooting for a hydraulic roller myself.

[afret]

Nah, I don't mind at all. The specs are 255/262 at .050 with .383 lobe lift and a 112 lobe separation. It will be installed at 4 degrees advanced at 108. This cam should give .674 lift on both the intake and the exhaust before lash with 1.76 rockers.
As far as springs, I don't know! I bought the Stage II heads from Keith, and he installed the proper matching springs on the heads with titanium retainers. I never did ask him for the spring specs. The cam, as you can see, is big enough to make lots of power, yet small enough to not be too difficult. Should be fun. The rest of the valve train and intake is a set of Harland Sharp roller rockers and stands, and a port matched Performer RPM with all the markings and logos ground off and bead blasted for a more original look, with a Quick Fuel 950 carb, all original gold color, with LeMans bowls. Should run good and look good too. If I can only get a darned block now......

Thanks for the info. Are you looking to get a new Al or iron block? I'm pretty happy with the Genesis iron block but a lot of people like the Pond and Shelby blocks. I just like iron blocks.

I've been running solid rollers on my street car for awhile now. I ran 3 different ones in my 428 and have a Lunati roller very similar to your cam in my new motor. 256*/264*, .3965 lobe lift, 110* LSA. I think it's just right for my car. I had a 264*/270*, 108* LSA roller in my 428 and it was little bit radical for driving around.

I think the pin oiling feature in a lot of the new solid roller lifters is helpful. The Comp lifters have that feature now. All the Cranes had it and it's optional on the Crowers. I used to run the Crane Ultra Pro lifters before but am running the Crowers with pin oiling now.

The hydraulic roller cams for the FE still require a bronze gear. Crane had a special steel gear for use with steel roller cams but Crane is no longer there...
I use a bronze gear and have had no problems with it. I've got several thousand miles on it and it has a bit of wear but is still fine. You just have to check it every so often. Just make sure the gear is located correctly on the distributor shaft so it doesn't bind on the thrust surface of the block.
I have one of those steel Crane gears but haven't used it.

[Chaplin]

Originally Posted by patrickt

Remind me again why a roller is better than a solid, flat tappet cam?

Ok, see my first post on this link.

http://clubcobra.com/forums/search.php?searchid=952333

[patrickt]

Originally Posted by Chaplin

Ok, see my first post on this link.

http://clubcobra.com/forums/search.php?searchid=952333

OK, I read it, and after I read it, remembered it from the first time I read it (it's copied below for everyone's convenience). I think I would tend to agree that rollers are better than non-rollers if, and only if, they have conquered the limited lifespan and distributor gear issue. You know as well as I that you can get a ridiculous amount of power out of a solid flat tappet cam in an FE. If we just skip over the "I'm afraid to break the cam in" issue then the increased potential power from a roller would have to be such that it offsets the limited lifespan/distributor gear issue (if those issues still exist). Would you agree with that?

I don't know if I agree with that. Because of the cam lobe profiles of a roller cam are much more aggressive and open and close the valves faster (whether solid or hyd roller) than a flat tappet cam, you will get better performance from a roller than you will from a flat tappet cam with similar or even slightly greater duration. The aggressive lobe shape of the roller cam effectively opens and closes the valves faster (as compared to a flat tappet cam) which allows the valves to stay open longer, thereby creating more "area under the curve" which provides the cylinders more time to fill at any given duration as compared to a flat tappet cam with the same duration. Or put another way, you can run a smaller duration roller cam (which means better throttle response and better idle quality, i.e., more streetable) but still have as much if not more power than you could get out of a flat tappet cam of the same duration or even slightly larger duration.

IMO, hyd roller is the way to go for a street cruiser. You eliminate the break-in problems associated with flat tappets, don't have to worry about roller bearings in solid rollers, and because of the cam lobe profiles, can run a smaller cam with better street manners without sacrificing performance of a larger flat tappet. Needless to say, I am having one installed in my motor as we speak.

__________________

[767Jockey]

OK, so I'm a thick headed Italian and it takes me a while to get things through my skull. I'm still confused a bit. If I understand correctly, the cam mounted gear that drives the distributor gear on a hydraulic roller is harder than that same gear on a solid roller????? Why?

As an aside, I distinctly remember some small cam company somewhere that had a setup that mounted their flat tappet cams in an electric motor driven device of some sort, and mounted the lifters in their proper position, and loaded the lifters down with springs. They then spun this contraption and broke in the cam on it before they sent it to you. Obviously, you would have to keep track of which lifter went onto which lobe, but that shouldn't be too difficult. Does anyone remember who this company is and if the technique works? I don't see whay it wouldn't be successful, and if it is why isn't everyone with a flat tappet cam doing it? It rather the lobes, if bad, went flat on the break-in machine than inside my engine.....

[Chaplin]

Jockey-
I think you are thinking of Cam Research. And just as an FYI, I know if at least one person who had them break-in their cam as you describe prior to delivery and they still wound up wiping a cam lobe. There are no guarantees.

Patrick- Fair 'nuf ;-)

[patrickt]

Originally Posted by Chaplin

Patrick- Fair 'nuf ;-)

So then you would agree that if one felt he could get sufficient horsepower for himself from a solid, flat tappet cam then a solid, flat tappet would be superior to a roller, for that person, if there was any additional maintenance required for the roller's distributor gear or if there was any shortened life of the roller's lifters, no matter how small that might be, correct?

[Chaplin]

Originally Posted by patrickt

So then you would agree that if one felt he could get sufficient horsepower for himself from a solid, flat tappet cam then a solid, flat tappet would be superior to a roller, for that person, if there was any additional maintenance required for the roller's distributor gear or if there was any shortened life of the roller's lifters, no matter how small that might be, correct?

As Jamo says, sounds like you've asplained it to your satisfaction.

Kidding aside, I don't necessarily agree. I will agree that if someone is willing to deal with the potential break-in issues because they prefer a solid flat-tappet, there is nothing wrong with running a solid flat tappet cam, as there can be no argument that they can make more than sufficient power.

However, remember, we're talking hyd roller, not solid roller. Production cars have been using hyd rollers with no issues for years in cars that see more mileage in their lifetime than your average 10 Cobras will see combined. Crane is making (or at least was making before they closed down and were bought out) a steel distributor gear to use with FE hyd roller cams that is advertised to wear like a factory steel- i.e, last 100k plus miles. I have one of their new steel gears on my dist now and will let you know how it works out (so far about 1500 miles and no issues at all (knock on wood)). But, even if Crane were not making the new steel gear and you had to replace the distributor gear periodically, that is a much easier (and faster) task than adjusting the valves. With the right tools and an asspert techinician you can change a dist gear on the side of road! Just ask Jamo. Try adjusting your valves on the side of the road. So for that reason, and the others mentioned, I still say a hyd roller is superior to a solid flat tappet for general street duty.

But if you like solid flat tappets, there aint nothing wrong with them at all.