[Half-Inch Stud]

What Cam lifter springs combo is proven to endure 11 hour highway rides, yet run the 1/4 mile into the 11s (3850 Lbs & iron heads)?

I presently have per 12.2 Signature ( Springs probably tired).
Still wary of Stout Roller combos due to Req'd Springs specs and how they might relax to ZERO by breakage, or relax too much for Strip RPMs.

Comes down to Mild Roller combo or proven HYD & Flat Lifters?

[Formulajones]

Doubt you'll find many here that drive the classics as much as we do, since we daily drive them.

I've criss crossed the country with them, more than 11 hours. Flat tappet and roller. Been on some pretty long cruises with big roller big spring stuff as well without problems. I set up dad's current hydraulic roller with a typical 150 lbs. seat pressure and 420 lbs. open. We just did Goodguys tour and 2 trips to Phoenix and back that are 200 miles a piece in 2 days. We had about 6 or 7 hours of drive time and well over 500 miles, it ran perfectly flawless, and went 10.87 at the track 3 weeks ago. My Chevelle is a roller with similar springs and it's been going for more than 15 years now and thousands of miles. I've never had a valve cover off since and I don't even think about it, runs mid 11's at a 4100 lbs. race weight.

The hot rod drag and power tour guys do it all the time and take things to extremes.

I'm not real sure what your concern is. If things are done properly a typical 150 lbs seat hydraulic roller spring should last many trouble free years.

[Cliff R]

There are many flat cams that will make the grade in a 455 build and get you into the 11's.

Being able to run 11's in going to be as much a part of how the car is set-up to effectively use the power. A good converter can be worth 1/2 a second at the track with no other changes. So can tires, DOT's will make the car a LOT quicker than most "street" tires.

If you have concerns with roller profiles, high spring pressures and long term durability I feel your pain.

I went with Crower HIPPO lifters on my HR cam back in 2009 for that reason. Lashed at .005" it's been dead solid reliable, whisper quiet and next to zero maintenance.

If going with a flat cam I'd do three things. Avoid super-quick ramps and excessively fast seating velocities that require a lot of spring pressure. I'd also put USA made Hylift Johnson lifters on it, and I'd send the cam out to be "coated".........Cliff

https://www.ionbond.com/

[Formulajones]

Like Cliff said, if you want to go flat tappet, there are plenty of hydraulic cams that will move a car into the 11's if the rest of the car is set up properly to harness it. They typically don't requires more than 120-130 lbs. seat pressure. I've been nitride coating the last couple of flat tappet cams I've done, along with the EDM holes on the lifter faces for extra oiling, and if you want to go to extremes you can have your springs cryo treated.

One of our current daily drivers is a solid flat tappet, nitride coated, EDM holes on the lifter faces, 120 lbs. seat pressure, and in the last 3 years I've logged 30,000 miles on it and it's been flawless. The lash hasn't budged.

[leeklm]

"I went with Crower HIPPO lifters on my HR cam back in 2009 for that reason. Lashed at .005" it's been dead solid reliable, whisper quiet and next to zero maintenance."

My experience as well- been running for three seasons with a stud girdle and the lash has stayed spot on! I have not done anything major like the power tour, but do have a few 300 mile round trip cruises on it, along with a few trips to the track each year.

Sent from my SM-G965U using Tapatalk

[shaker455]

I would think the most common is Comp 995 spring.

[Johnny406]

I'm certainly not the key expert on this but with similar aspirations, I'm going to take the 463 in my signature and freshen it up and move it to my 81 T/A to replace the 406. With that said, I am going to keep that Lunati Voo-Doo cam in it with the Rhoads V-Max lifters (now with a super lube groove option) and go back to iron heads (milled 6X-8 ported by Jack Ferris) with a Crosswind intake I bought from ACE @ PPR years ago. After reading Jim Hands book many years ago, I decided to try the Rhoads lifters but went with the V-Max race series and my car runs quite strong. That Lunati cam works good with nitrous too, I'm 3-1 racing Hellcats with a 170 shot.

[Half-Inch Stud]

Suppose my present HYD could do it. Did a thorough by-the-book cam break-in. Suppose all thst engine needs to check Spring pressures. ...and a rear seal.

As for the spare engine; the 0.442" lobes probably doesnot meet the grand touring goal.

[Formulajones]

I would guess it depends on the lobe profile and how aggressive it is, and what spring pressure is required to control it.

We are running .390" hydraulic roller lobes on the street with the spring pressures I mentioned above. .643 lift with a 1.65 rocker. They are a mix of Voodoo lobes on the intake and an older Ultradyne lobe on the exhaust, and duration in the 260's at .050. No issues, I don't even consider it a concern..

Before that we were running a solid roller with a .440" lobe which has been done successfully by many, as long as spring pressures are kept reasonable on a street car. Which they were at a typical 240 lbs. You'll find that's a pretty typical range to be in with a solid roller in a street car. Actually less pressure can be worse than too much. It ran perfectly for a few years and several thousand miles, and a few long distance trips, however one lifter did fail. It was Crowers bushed lifters with pressurized oiling, and these were used specifically due to the fact that the entire goal of the engine was primarily street car first, race car a distant second. According to Crower, there was no explanation for the failure, as so many others report success. I know of quite a few solid rollers in this range on the street still working, but usually engines built to that extreme aren't used on 10 hour road trips by the normal enthusiast. You do however see that done for things like Hotrod drag week.

[Johnny406]

I was looking around on the Isky site and I saw this, needle free bushing roller lifters.

http://www.iskycams.com/downloads/IS...ixFlyer119.pdf

[Steve C.]

My Crower Cutaway Severe-Duty solid roller lifters were converted to bushed bearing.

https://www.crower.com/rebuilt-your-roller-lifters

.4300" lobe lift w/ 1.65 intake and 1.6 exhaust
PAC-1243 valve spring rated 240 @ 1.900"

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[Formulajones]

Yep, that's exactly what we were using on the solid roller I mentioned above. Crower bushed rollers with pin oiling.

They still failed. Crower had no explanation but it looked to me the bushing just locked up the roller, turned the wheel into an egg shape and ate the lobe as a result.

Just one did it, rest were fine. Springs were perfect and lash was spot on.

[Half-Inch Stud]

Well, i just revisited the heebee geebees from the past 4 Posts

Flat HyD : Most likely Failure mode is an Exhaust Lobe wiping out.
Roller : Most likely Failure Modes are Busted Lifter, Spent Dizzy Gear, Busted Exhaust Spring, Busted #2 Exhaust Lifter Bore, maybe a bent pushrod, maybe a valvehead parts ways...we all got good Roller Rockers & Valve Retainers.

Almost sorry for asking, but im stuck thinking the wholes Roller valvetrain takes on cubic dollars to attain Reliable. The Flat HYD al least keeps driving with first aid.

[Steve C.]

And as a positive example it was not long ago HWYSTR455 posted how many thousands and thousands of trouble free driving with his solid roller combinations.


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[HWYSTR455]

Yes, solid roller, with 'street-friendly' lobes. They were not very aggressive, had a soft landing closing ramp, and lower than expected spring loads. I would have to go back and look, but believe the seat was 160, open 290. Crower standard roller HIPPOs.

Pretty sure I've posted that cam card several times, I had almost 90k miles on it, sold it to a board member, he ran it with no issues. Power brakes and AC car.

I would drive that thing hard all day, in road-race type conditions, thru the mountains, never a hiccup. Long trips all up & down the east coast, and several states to the west.

I checked lash almost every oil change, but only the 1st few checks required any adjustments, I wrote it off as typical new-engine/valvetrain break-in.

This time around, on the 535 build I'm doing, my builder recommended the Comp Endure-X severe duty lifters with pin oiling, builder has extensive experience with them, and assures me they will last in an high effort street/strip engine. We will see, he has yet to steer me wrong.

I will do a build thread on that car as soon as it gets rolling, and post specifics on the engine.


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[Formulajones]

Those seat pressures are what you typically see on hydraulic rollers, and the open pressure, even less. With pressures like that I wouldn't be concerned with a solid roller longevity.

[Steve C.]

I've had the same set of PAC valve springs on this engine for about 8 years. They are Pacaloy material, a proprietary spring alloy developed by PAC Racing to serve the high performance spring market. Like many, limited street use and not raced. Taken to the track a few times in the past only for interest. We check the spring pressure and valve lash generally once a year, maybe twice if it's in the shop for something else. With my .4300" lobe UltraDyne cam Bullet suggested if limited street use only, no racing, and at my lower 6000 peak power rpm then for the most part they said ok to 220-225 seat pressure. Any lower then change the springs.

Years ago on the Comp XE street solid roller cams the spring pressure was around 180 lbs on the seat.


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[steve25]

For a solid roller Cam kicking Titainum valves up to 6500 rpm or more I concider 180 psi on the seat the minimum!

[HWYSTR455]

I know those spring pressures I posted seem incredibly low, but no joke, that is very close to what it called for.

I found the cam card, but it doesn't show spring requirements. But I did find a previous post with info closer to when I installed it, and I quoted even lower seat pressures.

https://forums.maxperformanceinc.com...rower+cam+card

That was 6 years ago:

"It's a Crower custom, based on the 60451 grind, 247/254, .612, on a 114 LSA. I would have to dig the card up for the lobe patterns, but they are what some call 'slow ramp' lobes, and use moderate spring pressures. I think the springs are like 420 lbs max, but at max lift, it's I think in the 290 range. Seat I think is like 130. Again, would have to look it up, my memory isn't what it used to be."

I believe I have the head setup info, pretty sure the springs were Crower 68369, but think support specifically gave me a 'softer' set since it was going to be a street/strip:

https://www.crower.com/valve-springs...oy-dual-1.html

Granted, it shows a value of 215lbs at 1.950, but I don't think that was the actual value, it was lower. Those values are inflated, or I had a different set. That's just what the off the shelf cam calls for.

Since I wanted a wider LSA, due to the lobes used in the off the shelf profile, they had to use different lobes to get the desired LSA.

I had another solid roller, a smaller one, in a 455 in the 80s. It was a Comp 224/232 on a 112, with Lunati solid rollers, and that engine went 220k miles, one valve job around 120k miles. That too had lower than expected spring rates, and yes, I have notes that show the mileage. Pretty sure that was like in the 140 seat/260 open range.

Post 52, from 2008:

https://forums.maxperformanceinc.com...am+card&page=2

No rev limiters on either, second is a manual car, and I RPM'd them as far as the cam profile allowed.

As I mentioned, using the right profile makes a big difference, and with certain ones, you don't need big spring pressures, and that makes them live long on the street.

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[HWYSTR455]

That cam card has the job number on it, Crower could look up lobes and spring requirements using that.

Comp usually has a habit of an aggressive opening & closing ramp, slamming the valve shut. That's hard on parts, springs, seats, guides. Due to the closing ramp aggressiveness, they require higher spring psi. But they do have a number of lobes that are 'easy on parts'.


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