Converting 351W Non Roller to Roller lifters

LMH · #1 (**permalink**) 10-10-2012, 09:04 PM

Hey all
Has anyone had any experience with converting an older non roller cam block to a roller cam?
As I read about it, it appears that using production roller lifters is possible but the lifter bore needs to be ground flat for the dog bone and the center spider needs to be mounted. Sounds OK but then a small base circle cam has to be used. Any issues there?
How about linked after market roller lifters? More expensive but standard cams fit.
Thoughts or experience?
Larry

bobcowan · #2 (**permalink**) 10-10-2012, 09:30 PM

The issue is the height of the lifer bores in the block. When Ford developed the roller lifter, they essentially grafter a roller wheel on to the bottom of flat lifter - makeing it significantly taller. So, the cast the new block with a taller lifter bore. Problem solved.

You really have two easy options. You can use a standard cam, and link bar lifters. Kind of expensive, as the lifters run about $500 a set. But you have a greater selection of cams.

You can use stock Ford lifters, dog bones, and spider. And then use a reduced base circle cam. Somewhat cheaper, but just as effective.

Installing the spider in the lifter galley is pretty simple. Drill and tap two small holes. Do not do this with the cam bearings installed, as you could damage them if you drill too deep.

The dog bones are used to keep the lifters from rotating. Flat tappets need to rotate, or they develop flat spots. Roller lifters need to keep the roller wheel aligned with the cam. The dog bones need to sit flat on top of the lifter bore. Sometimes you need to do a little grinding to get everything to fit right. On my stock block, it only took a couple of minutes with a 4" grinder.

I would not choose to install a flat tappet cam in any windsor motor. It's too easy to convert to rollers, and there are some excellent benefits to be had.

Karl Bebout · #3 (**permalink**) 10-10-2012, 09:45 PM

Remember that you'll new new push rods since the roller lifters will be longer than your old flat tappets. There are different methods and tools for determining the ideal push rod length. Not real technical, but pretty important.

LMH · #4 (**permalink**) 10-10-2012, 11:36 PM

I'll have the engine builder install it and work out the pushrod length.
Is there a limit on the lift using production lifters? I have a set and the flat spots don't look like they can take a lot of lift.
Larry

blykins · #5 (**permalink**) 10-11-2012, 02:59 AM

Why would you want to? If the block is not ready for it, it's much easier to run a standard base circle cam and link bar lifters. Link bars are not bad at all...I use Morel lifters at about $375 a pop.

FWIW, I've run up to .640" lift on the OEM lifters/spider setup.

vector1 · #6 (**permalink**) 10-11-2012, 03:59 AM

i'm using link bar solid rollers in a non roller block now, no issues, checked the oil band before use to make sure everything was good on the base and at lift using a roller cam. i have heard and will perpetrate the fact or myth that some don't like the small base retro cams as they flex with the rumor of breaking. unless i already had and was set up for the spider/dog bone stuff i would probably use link bar, just looks better to me. bob has some good info above.

LMH · #7 (**permalink**) 10-11-2012, 12:05 PM

Hey Brent, is that the price you sell the Morel lifters for?
Larry

blykins · #8 (**permalink**) 10-11-2012, 12:06 PM

Yes sir....

Caprimaniac · #9 (**permalink**) 10-11-2012, 02:35 PM

Quote:

Originally Posted by blykins

Why would you want to? If the block is not ready for it, it's much easier to run a standard base circle cam and link bar lifters. Link bars are not bad at all...

X2

It's how most of the solid rollers are indexed too, and they can take alot of beating.

bobcowan · #10 (**permalink**) 10-11-2012, 10:23 PM

Quote:

Originally Posted by blykins

Why would you want to? If the block is not ready for it, it's much easier to run a standard base circle cam and link bar lifters. Link bars are not bad at all...I use Morel lifters at about $375 a pop.

FWIW, I've run up to .640" lift on the OEM lifters/spider setup.

Why? A couple of reasons to choose this option.

- The block "conversion" is really simple: drill and tap two holes, and make sure the dog bones sit flat.

- you can use factory Ford roller lifters. Inexpensive, easy to find, and will last just about forever. $126 at Summit racing.

- You can use a factory Ford spider and dog bones. $50 at summit Racing.

The down side is the cam shaft availability. There are fewer choices with a reduced base circle. But the choices are pretty darned good, and unless you have an odd requirement - like IR intake - then you'll probably be able to find one you like off the shelf.

Currently, I'm using Ford lifters, spider, and dog bones in a Dart Sportsman block, with a standard base circle, high lift, off the shelf cam. Works pretty darned good.

Life is full of trade offs and choices. Rarely do you find one choice like this that's always better than another.

LMH · #11 (**permalink**) 10-12-2012, 12:02 AM

Thanks guys for the info!
I'm going to talk to the engine builder about it but I'm leaning towards the link bar lifters.
It's more expensive but it just looks stronger and the cam I'm suggesting is a standard base circle cam. Appreciate the advice!
Larry

blykins · #12 (**permalink**) 10-12-2012, 05:49 AM

Quote:

Originally Posted by bobcowan

Why? A couple of reasons to choose this option.

- The block "conversion" is really simple: drill and tap two holes, and make sure the dog bones sit flat.

- you can use factory Ford roller lifters. Inexpensive, easy to find, and will last just about forever. $126 at Summit racing.

- You can use a factory Ford spider and dog bones. $50 at summit Racing.

The down side is the cam shaft availability. There are fewer choices with a reduced base circle. But the choices are pretty darned good, and unless you have an odd requirement - like IR intake - then you'll probably be able to find one you like off the shelf.

Currently, I'm using Ford lifters, spider, and dog bones in a Dart Sportsman block, with a standard base circle, high lift, off the shelf cam. Works pretty darned good.

Life is full of trade offs and choices. Rarely do you find one choice like this that's always better than another.

Not really a trade-off here. He doesn't have a Dart block. It will all be dependent on the labor that his machinist charges, whether or not it would be +/- for him.

I can grind cams with any base circle you want, but in a regular Factory block, I would feel more comfortable with a standard base circle and link bars.

Texasdoc · #13 (**permalink**) 10-12-2012, 08:46 AM

I also have a 351w non-roller. I used the dog bones and spider. No problems. The linked rollers look better but are much more $$$.

blykins · #14 (**permalink**) 10-12-2012, 01:57 PM

Just depends on what condition your block is in.

Considering the cam being the same price either way, you're looking at either $375 for a set of link bar lifters or $40 + $120 for a set of OEM lifters and a spider. The price difference would be eaten up quickly if the dogbones don't sit flat against the block and milling would have to be done in addition to the normal drilling/tapping.

Aftermarket blocks don't have that issue, but if you've ever had a Cleveland or Windsor block that needed work, you'd understand what I mean....haha