Why a roller?
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Why a roller?
My machinist told me that I should not put a roller cam in when I rebuild my 351w (I MAY stroke it to a 396). He says money is better spent in heads (I agree), but everyone else seems to think that roller cams are so much better than any hyd. flat tappet. Are there any negatives (besides $$$) to using a roller cam? This is going in a daily driver EB. If going with a roller cam is that much better, does it really make a difference if I use a roller block or not (I know that it would need to be converted) or would any block w/ a conversion work just as well???
ANY help would be truly appreciated, as I would like to get this thing going....
ANY help would be truly appreciated, as I would like to get this thing going....
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Joined: Jun 2001
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Converting a non roller block to roller is not a big deal but cost a couple extra dollars.
These assume you have a non roller block.
One method, purchase the spider retainer, "H" bars, factory roller lifters for a roller 302, they are listed as 302/351. You will then need to have two holes drilled and tapped in the center of your oil valley. Then you will need to purchase a reduced base circle cam. Problem here, your gonna have a hard time when you try to resale the reduced base circle cam. As it will not work in standard roller applications.
Second method, doesn't get much easier. Purchase retro-fit roller lifters that connect two lifters with a bar. Simple you install these as you would any lifter, install a roller camshaft and measure the pushrods for proper geometry, as you should in the first method as well, your done. The problem here is the price of the retrofit lifters they run $350-400 but you would have better luck selling the camshaft as it would be a standard piece. However, the retro lifters are stronger by design as compared to the stock pieces in the upper rpm, or so I have been told, it makes sense. Just looking at the two you will see how much stronger the retro fit lifters look compared to the stock unit.
In both cases when you switch to a roller cam you will need to change the gear on the distributor in most cases, some cams do not require it but most do, check with the manufacturer of the camshaft. The first method with be a couple of hundred cheaper, potentially, but the second is stronger and very easy and you have the benefit of using any standard roller cam new or used.
As far as power, a hydraullic cam is fine, the benefit to the roller is you can have a more aggressive cam design yet smoother idle. Better cam profile, blah blah blah, do you need one to make a lot of power and be dependable, no. It is really up to you, I can't think of a negative reason not to go roller besides the price. Put the money you would invest on roller cam install on a little nitrous oxide system then the benefits of the roller would be dwarfed by the output of the nitrous oxide. Just kidding. Hope this helps, later
These assume you have a non roller block.
One method, purchase the spider retainer, "H" bars, factory roller lifters for a roller 302, they are listed as 302/351. You will then need to have two holes drilled and tapped in the center of your oil valley. Then you will need to purchase a reduced base circle cam. Problem here, your gonna have a hard time when you try to resale the reduced base circle cam. As it will not work in standard roller applications.
Second method, doesn't get much easier. Purchase retro-fit roller lifters that connect two lifters with a bar. Simple you install these as you would any lifter, install a roller camshaft and measure the pushrods for proper geometry, as you should in the first method as well, your done. The problem here is the price of the retrofit lifters they run $350-400 but you would have better luck selling the camshaft as it would be a standard piece. However, the retro lifters are stronger by design as compared to the stock pieces in the upper rpm, or so I have been told, it makes sense. Just looking at the two you will see how much stronger the retro fit lifters look compared to the stock unit.
In both cases when you switch to a roller cam you will need to change the gear on the distributor in most cases, some cams do not require it but most do, check with the manufacturer of the camshaft. The first method with be a couple of hundred cheaper, potentially, but the second is stronger and very easy and you have the benefit of using any standard roller cam new or used.
As far as power, a hydraullic cam is fine, the benefit to the roller is you can have a more aggressive cam design yet smoother idle. Better cam profile, blah blah blah, do you need one to make a lot of power and be dependable, no. It is really up to you, I can't think of a negative reason not to go roller besides the price. Put the money you would invest on roller cam install on a little nitrous oxide system then the benefits of the roller would be dwarfed by the output of the nitrous oxide. Just kidding. Hope this helps, later
Last edited by jwtaylor; Dec 8, 2003 at 08:10 AM.
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From: Atlanta, Georgia, USA
The biggest difference I noticed when switching from flat tappet to roller is the overall smoothness improvement of the motor. It will idle and accelerate more smoothly, and it will not require a break-in. Flat tappet cams do wear down, even if broken in properly, which will contribute to the metal in your oil. These benefits may be almost negligible, as flat tappet engines have been built for decades and most live long happy lives, but you can typically expect another 30-40 ft*lbs of Torque at any RPM due to the reduced drag.
BTW, I used method 3 to convert: Get a roller block from the get-go, and then use boneyard spider plates and H-bars, with new Motorsport roller lifters ($109 @ Jeg's). If you use a stock roller cam with Ford heads, you can just use stock pushrods and not worry about the geometry so long as you don't have the block or heads shaved. TK
BTW, I used method 3 to convert: Get a roller block from the get-go, and then use boneyard spider plates and H-bars, with new Motorsport roller lifters ($109 @ Jeg's). If you use a stock roller cam with Ford heads, you can just use stock pushrods and not worry about the geometry so long as you don't have the block or heads shaved. TK
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Thnks for your replies. I have an '85 block already in my Bronco. I have been on the lookout (not to serious) for a roller block, but as you know, they can get a little pricey. I really like the idea of installing one when I rebuild my motor. I would like the smoothness and off-idle torque (going in a '68 Bronco), a little reduced friction would not hurt either. The lifters with b ar-links really seem the way yo go, but you are right, they are quite pricey. Are ther any durability concerns with a reduced base cam?
