Solid vrs roller cam on a street motor

[m.maxwell]

I have sacrificed an engine twice using a solid roller on the street, even with a street roller profile. I tried a different lifter brand the second time and got the same results. This was in a "driven" car. I am about thirty miles from the track with california's "always idling" freeways. I am certain that this was the major contributor to the lifter death. Some people tell stories of "years of driving" using solid roller lifters but that was not my experience. I am now using a solid flat tappet and making about the same power but the cam profile is quite a bit more radical than the roller to make the same power. Idle vaccum is 5 inches in gear@ 1000 rpm's. Car has power brakes and stops fine.

[Cammer]

Even with proper oiling, sustained idling in traffic can take out a solid roller camshaft.

Manufacturers should test their products on California freeways!

[PackardV8]

Greetings, All,

We've been through this a bunch of times, but is this a fair recap?

1. OEM hydraulic roller cams live long and prosper on the street. They can idle forever. Thus, the roller concept is OK on the street.
2. Aftermarket hydraulic roller cams of serious lift and duration seem to last pretty well, so CompCams and others know how to make them.
3. Are street roller cams really streetable? - CompCams states definitively they are. They say solid street roller cams with appropriately designed pressure-oiled lifters and moderate spring pressures will work - do they warranty them?
4. Rev kits seem to help by keeping the roller tight against the cam, thus rolling, rather than sliding or skidding.
5. So where is the fatal combination? What is the max spring pressure, lift rate, max lift which is safe to idle extensively? m maxwell and cammer indicate no solid roller is safe. what say the rest of us?

thnx, jv.

[Ed-vancedEngines]

Jack,
I will answer some of your post.

For years on my own personal cars, I ran both solid mechanical and solid roller lifters and I had no negative issues I knew about. All of my personal performance cars had clutches and 4 speeds. That tid bit of info I thin is what is important. Because they had clutches, my idle oil pressures were always up to 35# - 40# with free idling rpm # or 900 - 1000.

Not a long time after I begain building street engines for customers to use, I made some horrorifying discoveries. I was setting seat pressures in the 200# range as I had always done with my own with roller cams.

One cusatomer had a lifter go bad and wipe out his billet cam I had gotten from Crane. I took care of him and got the mess cleaned out of the oil galleries and the engine and bought him another cam just like the one that was damaged and two new lifters. He was running it and it seemd to be holding up ok, when I re-checked his lash adjustments in a couple of weeks. SB Chevy.

Not long after that incident, I did a BB Mopar with another Billet Roller and solid lifters. IT too ran ok. That is it did for awhile.

That first one cam back to me with a slight knock again. Checked valve lash , and not good. Checked the total lift in comparision to the others on the same head. Not good. Pulled intake, and lifters. Well I tried to pull lifters. One was stuck in lifter bore and it would go down but not up. Used a slide hammer and yanked it out. Bottom of lifter was spread, and roller was still there but minus the needle bearings. Cam was once again history.

While I had that SB Chevy down for the cam lifter issues, that Blasted Mopar came back with same problem again.

I was stumped and was veray mad. This was stupid. I had never had problems with cams or lifters before on my own cars and I had even ran as high as .700 lifts on the street.

I was fighting mad at Crane by now. They blamed me for using a solid lift roller in a street engine. According to them, it was the prolonged low oil pressure idle periods while idling in gear, that was probably getting the lifters. I did send those lifters to them at Crane for them to be diagnosed for problems. They wanted me to try reducing seat pressures down to 140# psi. I refused and we were done.

I ended up getting a Hydraulic Roller for both engines, with Hydraulic Roller Lifters too. I did get some help in paying for all that mess from the customers, So I didn't have to take the full hit of lifters too.

Guess what folks, Both of those were back before the year 2,000 and both engines are still running on the street.

Becuaee of some stroker issues, I came up with a need for a small base circle hydraulic roller cam for a street engine. Harold Brookshire and myself, equally came up with a Hydraulic Roller design that would still make some good power, by me adding some larger ratio rockers to the package. It was not Harold's fault or mine that we had to use the bigger rockers to get what we wanted. Part of it was on purpose but the rest of it was the Equipment that Lunati was using wasa Berco Cam rionder which needed an existing pattern to trace from. We combined existing lobe designs from other engines to get what we wanted. Or at least close to it.

With the Bigger rockers we ended up with a 245 deg intake and a 257 deg exhuast @ .050 with total lifts of .615 and ..595 on a 114 LSA. It was to be street driven and with nitrous when racing. iT also had all power and brakes. That engine believe it or has good idle vacuum for the brakes, and with the parts I used and valvetrain setup, it is comfortable at 6,900 rpm on revv limiter and is still running to this day 5 1/2 years later and has not one time had to have valve lash re-adjusted for any wear.

So, Since those two different failures becuase of the low oil presures at idling while in gear. I quit putting in solid rollers for street. Maybe we are giving up some power. Don't underestimate what a good cam designer can do now with a hydraulic roller though. They make lots of trouble free, maintenance free power.

Ed

PS
About Comp Cams advice givers or recommendations. I either ignore or pay little attention. That stupid few dollars cheaper black iron street roller cam is in my opinio n someone's idea of a joke.

If you follow their suggestions to get correct valvetrain geometry and were to have any serious cam you will eother blow something, or at the least will create too much side pressure on the valve during it's cycles.

IF you follow their advice and valve spring recommendations and spring setup, you will do good to get 6,200 to 6,300 rpm. No problem though. They can sell you a revv-kit to extent your rpm some.

I do like a lot of the Comp Products though. I use their cheaper Hydraulic Roller lifters, and with a seat pressure of 145# to 150# and an open of 360# appx, I have no issues getitng 6,900 rpm with no revv-kits. Like I said. I have just such a setup taht is still running and has been for over 5 1/2 years.

I think that means it is pretty reliable.

Ed

[bigjoe1]

I do NOt have any problems with solid rollers cams. I always tell the customer to NOT let the engine idle slow. (EVER) 15 to 1600 is the slowest I reccommend to everyone. Simple, but NO problems at all.

JOE SHERMAN RACING ENGINES

[PackardV8]

Greetings, Ed and Joe,

This is the stuff we need to put together a matrix to keep our customers from making bad decisions on street solid roller cams:

1. Everyone wants it all - bragging rights about long duration, high lift, fast action, but with comfortable idle, high vacuum and long lift. bigjoe1 says 1500 RPM idle is the key to solid rollers living on the street. This will wake up many less-than-serious racers and get them to go for a hydraulic roller.
2. Ed agrees low idle speed and concomitant low oil pressure is certain death. 1,000 RPM and 40 PSI are his minimums.
3. What about spring pressures? What are the maximum recommended pressures for engines which idle? I personally feel the necessararily high spring pressures are the real culprit.
4. Secondarily, the incredibly fast action of today's roller cam profiles take the roller on the lifter from no-load to punishing load to no-load so fast, the needles see a point loading. Maybe UDHarold could give us some general guidelines as to max recommended rates for idling.
5. Rev kits may not be about revs at all, but about keeping the rollers moving at the speed of the cam surface and keeping them lubricated. Can this be why hydraulic rollers live and solids die under the same profile and spring pressures?

Great stuff, guys. Lets get this all in one place and consider making the matrix a "sticky", because it comes up all the time in different ways.

thnx, jv.

[m.maxwell]

As I stated earlier, I have heard tales of people being successful with solid roller's on the street, I'm just not one of them. To suggest that a street car with an automatic can drive around in this california type traffic idling at 1600 rpm's in gear is a stretch. That would require a pretty loose converter. I run a 4000 rpm stall in my car and it remain's driveable with caution, but idle's in gear at 1000rpm's @ 40psi oil pressure. I think most of us with solid roller "real world" experience realize the financial risk involved. While hydraulic roller technology has improved as of late, there is still a shortcoming where ramp rate become's an issue. I don't think it has surpassed the potential of a solid flat tappet. This is only my opinion and I'm certainly no expert.

[Ed-vancedEngines]

I really do not think there is any disagreement here between BigJoe and me on this. I do kniw that he favors the Solid Roller cams though becuase the can produce more power. NO disagreement there at all.

I also know that even shelf stock hydraulic and hydraulic roller cams are hands above now, what they used to be with performance. I can not imagine me doing less than .590 lift stuff with anthing solid now except when the desired rpm will exceed the limitations of the hydraulic capabilities.

Most of this has much to do with the person who will be driving it. Joe and I both agree on that too.

The two guys I had my early bad experiences with, taught me to better qualify my customers.

The guy with that Mopar on the day he decided he had an engine knock, he called me on the phone to tell me what it was sounding like. I told him it could be several different things and he needed to get a wrecker to bring it to me. Appx 30 minutes later he drives up in the car telling me that he was only 22 miles away when it started knocking and he was talking to me on the phone, so it was a lot quicker to drive it than it was to wait on a wrecker. Can anyone say *Bad Decision*?

The first guy with the SB Chevy? Oh he was a champ. He called me on the phone from his house in Garland Texas and told me something was wrong becuase he had no oil pressure after all the previous was re-done and I had a hydraulic Roller in it by then. I asked him about the oil condition and of course it had been recently changed. I suggested he call a towe truck and bring it to me for me to check. About an hour later here he comes driving up in front of the shop with it. I go out there and ask him what the problem had been. His response was he didn't know that is why he was bringing it to me for me to check. He had driven it with zero oil pressure all the way from Garland Texas to Pnalo Texas which is appx 12 miles from where he lives with zero oil pressure. Oh' The problem? His oil filter was so full of trash and dirt it would not allow any oil to flow through it. Needless to say, He got a filter adapter with a By-pass put on it after I discovered that problem.

Now on the other side of this question, I have a few, and I mean a very few customers with really serious streetable engine with some really big cams that take very good care of the engines and even at a traffic light or a traffic jam will kick it into neutral or park to not let it idle. Those have no problems with solid cams or solid roller cams of even above .750 lifts (rollers).

So for me to give advice to here that who knows who will be reading about what to do with a street driven engine, I still will hold to the Hydraulic Roller with correct spring pressure settings, as I have earlier and often stated. I have some very strong daily drivers with them that will still rev to 7,000 rpm or to 6,800 rpm, depending on other things.

As I said in the beginning of thios post. I do not think I am arguing with Big Joe at all. The Hydraulic Roller is pretty much idiot proof.

Ed

[CamKing]

The biggest problem with Mechanical Rollers on the street, is most guys don't think they need the top of the line parts to run on the street.
To run Mechanical rollers on the street, you need the good $500 lifters, and most people figure they can get away with the cheeper stuff, because they're not turning as much RPM. You also need to make sure the cam profile is gentle enough for the street. The maintanance on a street engine is not going to be as often as a race engine, The lash opening up just a couple thousandths could do a lot of damage with an aggresive profile.

[PackardV8]

Greetings, Guys,

OK, we're getting there slowly, so lets continue to put some specifics, based upon experience, on a grid and agree/disagree on them as a guide for running solid roller cams on the street.

1. Idle speed - Ed's minimum 1,000 RPMs, but bigjoe1 says 1500 is better
2. Oil pressure - Ed's minimum 40 PSI at hot idle.
3. Lifter brands - what has worked for you? Isky Red Zone, Crower?
4. Spring pressures - what are the max seat/open you feel safe for extended street use?
5. Lift - what is the max lift you would recommend?
6. Rate - what is the max rate you would recommend? Does camshaft diameter and lifter diameter change your recommendations?
7. Duration/overlap/lobe separation/rocker ratio - what other cam variables affect street driving but not necessarily lifter life?
8. Rev kits - Y/N and direct experiences to back up the opinions
9. Oils/additives - do EOS or other additives or oil brands have any effect on roller lifter life span in street-driven engines?

thnx, jack vines

[Ed-vancedEngines]

Hey Jack,
You putting wordfs into my mouth , there, young man .

The 40 psi was what my own persoanl engine idled at around 1,000 to 1,200 rpm. That was with a clutch disengaged or the car in neutral though.

I would say though that me personally do not like to see anything lower than 30 psi if it has a solid cam. I don't ever want to see any of my engines idling below 20 psi with hydraulic or what even in gear if it is a street engine. If it is a race engine that better not get that low.

I agree completely with the prssure fed lifters or at the minimim, the pressure grooved lifters or grooved lifter bores with any solid on the street.

Also something else to know. Not only are solid lifters kmkilled by low rpm idling with low pressures, the valve springs don't like it either.

Idling a race engine is one of the harder tasks you are requiring it to do. Idling is harder on the valve springs than a full romp down the track. Idling is harder on lifters too.

For what it is worth going on the extreme side of things, I am currently developing a radical street engine for limited streetability, but still drivable that will be seeing .846 open intake lift and .799 exhaust. It is not hydraulic. It is using the best pressure fed lifter I use and they are in the .904 size.

Now that should give some fire to this discussion.

Ed

[MadBill]

Thanks for broaching this subject, crazy! Most timely for me, as my Rip Van Winkle 495 BBC, strictly street (7,200 RPM max) project is finally about to stir. A big solid roller and 'all the lift that will live' is a given, with a nice round 3/4" being the tentative target.

So far what I've gathered is that many feel needle roller skew and/or jerk is an issue, lots of oil flow is critical, low RPM idling is a killer, ditto wide lash/lack of maintenance, and pressure fed oiling is a huge plus. It would appear a rev kit would address several of these issues, as would a non-needle roller design, gentle and moderate lift lobes and low spring pressures. Obviously the last three are contra-indicated for my application!

After much pondering, my plan is to go with a stout-but-not-crazy-aggressive tight lash lobe, adequate-but-not-the-usual-massive-overkill spring pressures and Isky EZ-roll option Red Zone lifters. With my engine specs, a manual tranny and no freeway congestion within 100 miles, adequate idle speed should be a non-issue.

<EDIT> OK, started this right after Cam King's post, before Jack's or Ed's last posts, but if you snooze (or go for a coffee) ya lose! Nonetheless, much is in agreement.

[bigjoe1]

I am in agreement with everything so far. There is so much that the individual has to do with all this, I can NOT strees this enough.If the guy is NOT willing to put it in neautrall when he comes to a stop, HE should NOT have anything this radical. There is a fine line between a street driver racecar, and what is really a street car. My son Steve was a street racer for years, and he drove some serious race engine stuff on the street. I do feel that a rev kit is the best possible thing for this if they make one for your engine. Old man IIsky himself told me that they would increase the life of the roller bearings by 5 to 10 times normal street life.
It still comes down to the driver of the engine. some guys just know what to do, and some dont.

JOE SHERMAN RACING ENGINES

[MadBill]

Speaking of rev kits, seems to me that much less than the typical 30 to 50 lb. spring force would be enough to help rollers live. All that's truly needed is to eliminate the lash and thus prevent low RPM rotation start/stop, since the consensus is that higher RPM durability is not an issue.
Something as simple as a light spring between a seat wedged on the bottom end push rod taper (or a light press fit on a constant diameter one), pressing down on the lifter and so maintaining the roller contact, might suffice...
(Might even run quieter at low RPM, since the lash point would be buried in the valley, rather than up under a tin cover on the top of the engine...)

[PackardV8]

Hi, bill,

Not following you here on the effect of a rev kit on lash point. If the lifter and pushrod are held against the cam, wouldn't all of the lash slack be under the tin cover at the top between the pushrod and rocker?

thnx, jv.