roller camshafts

[Mike H.]

I read the thread from Aug. 2006 about roller camshafts. Have opinions changed since then? One advantage that was not discussed is roller camshafts don't wipe out cam lobes on start up. Are suitable grinds available now for BB 400hp.
CORDially Mike

[Joe L.]

Re: roller camshafts

I read the thread from Aug. 2006 about roller camshafts. Have opinions changed since then? One advantage that was not discussed is roller camshafts don't wipe out cam lobes on start up. Are suitable grinds available now for BB 400hp.
CORDially Mike

Mike------


In my often-stated opinion, hydraulic roller cams are the only way to go, especially for any engine originally equipped with a flat tappet hydraulic cam. PERIOD.

You will not find a roller hydraulic cam of the exact same grind as the L-36/L-68 cam but there are many suitable grinds now available. However, you have to use aftermarket roller lifters with cross bar anti-rotation feature since you cannot use a Gen VI type set-up with GM lifters. Theoretically, you could use a GM cam if you can retrofit a camshaft thrust plate to the front of your block. However, GM has only a few roller hydraulic cams available for big blocks so you have much better selection of cams if you go aftermarket.

Use only a camshaft which has a pressed-on, ductile iron distributor gear or one that uses a monolithic steel gear that is compatible with a GM melonized distributor gear (gear on the distributor). NEVER, EVER use a roller cam that is compatible only with bronze distributor gears---NEVER, EVER, EVER and no matter what anyone else tells you. For racing they are ok since racing engines are torn down frequently but NOT for a street engine.

[Stephen B.]

Re: roller camshafts

Mike
If you don't mind more horsepower,more torque,smoother low end performance,oh and did I mention no apprehension about loosing cam lobes then run to the nearest Comp Cam dealer and buy a new bump stick for your ride. I personally know several C-1 and C-2 owners that can't wipe the smile off their face after this installation.
I have two friends that are original owners of rare 60s Fords who lost motors recently do to lobe failure. one is a 66 turbo Shelby Mustang, the other is a 427 dual quad 66 Fairlane . Both are currently receiving rebuilds with rollers.
There's a reason way GM started installing roller cams in all their small blocks from 96 on,and it wasn't because they were cheaper.
Stephen Barrett (21558) 59,66,71,73

[Michael Y.]

Re: roller camshafts

I have installed a hydraulic roller in my 64 365hp, and I cannot say enough about it. It was easy to install, and it works flawlessly. I have no need to run special oil, and there is very little worry about rounding off lobes. The only disadvantage, I can see, is the initial cost.

[Tom P.]

Re: roller camshafts

I feel Joe and Mike's comments (#2 & 4) have provided you as much information as you will ever need.
The 4 main points are:
Better all around performance
Gear compatabilty
BIG initial cost
No worries about lobe wear.
Yes, WITHOUT QUESTION, a retro roller cam (for either BB or SB) is considerably more expensive than a flat tappet cam---------------------------------------until the day comes that you have to halfway tear down the engine to replace the cam/lifters!

Remember the old Fram commercials, "You can pay me now or you can pay me later"? That was the ONLY thing Fram EVER had that was any good!

[Stuart F.]

Re: roller camshafts

Am I to assume that all the roller cam installations referred to here also had roller rockers? or is that not a consideration?

Stu Fox

[Clem Z.]

Re: roller camshafts

remember in blocks originally equipped with a flat tappet cam you have to come up with a way to hold the cam back in the block. flat tappet cams have the lobes ground on a angle that causes the lifters to "push"
the cam rearward in the block. the best way is to braze a reinforcement inside the timing gear cover and use a needle bearing thrust bearing in the front of the cam and limit the "end play" to about .005/.010

[Jim T.]

Re: roller camshafts

remember in blocks originally equipped with a flat tappet cam you have to come up with a way to hold the cam back in the block. flat tappet cams have the lobes ground on a angle that causes the lifters to "push"
the cam rearward in the block. the best way is to braze a reinforcement inside the timing gear cover and use a needle bearing thrust bearing in the front of the cam and limit the "end play" to about .005/.010

Way back in 1968 I installed a "mild" hydraulic cam in my 1964 327/300. The cam and lifters were from Crower, bought directly at the manufacturers place of business. The cam kit came with a round piece of wood that was made to place in the front of the camshaft before putting on the timing cover. Do not know how long the wood would of lasted because I had to sell my 64 in 1969.

[Joe C.]

Re: roller camshafts

I read the thread from Aug. 2006 about roller camshafts. Have opinions changed since then? One advantage that was not discussed is roller camshafts don't wipe out cam lobes on start up. Are suitable grinds available now for BB 400hp.
CORDially Mike

Mike,

I wouldn't worry about cam/lifter wear if you continue with a blueprinted match for the original cam:

3883986: 1965-72 Hyd: .460I/.488E 213I/217E See Note 2

Note 2: 396 325/350hp L-34/L-35, 427 385/390/400hp L-36/L-68, 454
345/360/390hp LS-4/LS-5, good torque/HP

Those are VALVE lift dimensions (not lobe lift) for a theoretical 1.6 rocker ratio, which is, actually, somewhat less than actual @ POML.

Those are 0.050" durations.

This is a very mild cam, and Rotella or equivalent should supply plenty of phosphorous to protect the lobes/tappets.

The sole reason that I would go with a hydraulic roller, would be to get a more aggressive ramp rate and more lift, as well. Otherwise keep your hydraulic flat tappet cam and save your money.

[Clem Z.]

Re: roller camshafts

Way back in 1968 I installed a "mild" hydraulic cam in my 1964 327/300. The cam and lifters were from Crower, bought directly at the manufacturers place of business. The cam kit came with a round piece of wood that was made to place in the front of the camshaft before putting on the timing cover. Do not know how long the wood would of lasted because I had to sell my 64 in 1969.

if the flat tappet cam was ground correctly you do not need any thing to keep it in place. i had a flat head ford back in the 50 that i had to put stop in the front of the cam to keep it in place but nothing since then.

[Clem Z.]

Re: roller camshafts

Mike,

I wouldn't worry about cam/lifter wear if you continue with a blueprinted match for the original cam:

3883986: 1965-72 Hyd: .460I/.488E 213I/217E See Note 2

Note 2: 396 325/350hp L-34/L-35, 427 385/390/400hp L-36/L-68, 454
345/360/390hp LS-4/LS-5, good torque/HP

Those are VALVE lift dimensions (not lobe lift) for a theoretical 1.6 rocker ratio, which is, actually, somewhat less than actual @ POML.

Those are 0.050" durations.

This is a very mild cam, and Rotella or equivalent should supply plenty of phosphorous to protect the lobes/tappets.

The sole reason that I would go with a hydraulic roller, would be to get a more aggressive ramp rate and more lift, as well. Otherwise keep your hydraulic flat tappet cam and save your money.

i agree that the cam lobe wear was caused by the type of lobe design used on after market cams and cheap off shore lifters. if you use stock lobe design and stock tension rate springs you should have no problem.

[Stephen B.]

Re: roller camshafts

Am I to assume that all the roller cam installations referred to here also had roller rockers? or is that not a consideration?

Stu Fox

Stuart
This topic has been beaten to death on this forum and the opinions sometimes are very strong so hopefully we won't go there again.Having said that I will say that it's ONLY my experience and therefore opinion that every motor that I have anything to do with has at the very least roller tip rockers. I feel very strongly that it's short sighted to NOT use at least roller tip rockers in a roller cam motor. If you have the budget to consider a roller cam don't cheap out on the rockers.I have never experienced a problem nor has anyone I know.
Let me repeat this is only one persons opinion.
Stephen Barrett (21558) 59,66,71,73

[Stephen B.]

Re: roller camshafts

Clem
Just an opinion but, I have always thought it wise to buy a cam kit that included the same brand cam ,lifters,push rods,and timing chain.I also have always felt comfortable using the springs recommended by the manufacture for that cam. I never try to out think the engineers be they GM's or Comp Cam. I have always felt it very important to shim springs to obtain the recommended height and therefor uniform pressure. Just common sense to me,not rocket science.
Stephen Barrett (21558) 59,66,71,73

[Michael H.]

Re: roller camshafts

I think the REAL reason why roller lifters are now used in newer engines is being ignored here. This has been discussed here in the past and the reason is not because roller lifters consume less energy because of reduced friction. Roller lifters don't reduce friction.

All else being equal, there would be almost no measurable difference in power between a flat tappet cam/lifter and a roller cam/lifter.

[Duke W.]

Re: roller camshafts

If you want the engine to exhibit its OE idle and low speed operating characteristics, massaging the heads will give you more bang for the buck than an aftermarket roller cam, most of which have too much overlap that will screw up the idle and kill low end torque.

The OE cam is a very good design - similar to the L-79, but slightly milder, which makes huge torque right off idle in the longer stroke big block, and the head work will make usable power to about 6000. The actual .050" durations are 214/218 with a inlet POML of 110 and a LSA of 115.

If you want to trade a little low end torque for more top end power, install it five degree retarded, and if you want to restore the low end torque and then some, use a 454 crank and pistons with a target compression ratio not to exceed 10.25:1.

As far as the valve train is concerned, the OE components work fine, but make sure you use the second design dual valve springs that have been discussed here a number of times. The early single spring/damper design has a high failure rate.

You don't need special oil for any OE cam and valve spring setup. Any CJ-4 available at Walmart is more than adequate, and if you use replacement parts from Tier 1 OE suppliers like Federal Mogul and Dana Corp. it won't wipe out lobes like Comp Cams flat tappet cams are prone to.


Duke