Got a stumper.

[Alvor315]

What is the maximum cam lift to travel ratio of a regular lifter cam? of a roller lifter cam? :roll:

Hehehe. And you thought the title was a joke!

Put another way: What is the greatest slope of camshaft lift to lobe surface distance before lateral stresses are detrimental?

Am I thinking just a bit too hard about how my engine is put together?


Thanks,
Allan

 

[rbohm]

8) ramp rates differ on flat tappet engines due to lifter diameter. early engines use small diameter lifters, and thus had slow ramp rates. mushroom lifters came along and allowed for much faster ramp rates, but still slow compared to roller lifters. you are however thinking too much on your engine build, unless you are building a race engine.

 

[Alvor315]

Right after I posted this, I started looking for 1 the terminology and 2 roller lifters that would work in our engines.

Ramp rate. #1 solved.

I read the post Mike made about getting roller lifters for our blocks. Why should roller lifters need the tie bars? If I'm not mistaken, I believe I read somewhere that the first roller lifter engines had guides cut into the lifter journals. Is it no longer possible to get those types of lifters, and machine the guides? Then you wouldn't need the tie bars for the lifter valleys 1 and 12.

 

[rbohm]

8) tie bar lifters are the easiest to do, and thus hte least expensive. that said, there is no reason that roller lifters with a built in guide that requires a groove cut in the lifter bore cant be used.

 

[Alvor315]

Boy, you're really good with this vocabulary stuff.

 

[StrangeRanger]

If you were to cut into the lifter bores for a guide, might not that upset the oiling pattern for the top end? Nothing that could not be fixed but still a consideration. The tie bars seem easier.

 

[Alvor315]

This is what I had in mind. Took forever to find these.
http://www.jeselonline.com/v2/index.php?categoryid=16

With a guide that small, I think the impact on the oil flow would be minimal.

Funny thing about me is that I can't stop until everything works better than it's ever supposed to.

In theory at least.

 

[StrangeRanger]

That type requires that lifter bores be opened up and a bronze bushing be pressed into each one. The bushing is slotted for the anti rotation key and cross-drilled and grooved as necessary to re-establish a correct oiling pattern to the pushrods and rocker arms.

You're trading a lot of precision machine work for some reduction in valvetrain inertia. If you're building a big budget NASTANK engine that has to live at 9000 RPM for 8 hours between re-builds, this makes a lot of sense. If you're building a low revving 300 for the street (or street/strip) not so much

 

[rbohm]

8) nice find on the jesel lifters. they have always been an innovator in the automotive aftermarket. as long as the keyway groove isnt too long, there is no interference in the oiling system.

as for the vocabulary, ah iss a publick skule gradgiate.

 

[Alvor315]

StrangeRanger, I believe you missed one of the lines directly after the link I provided.

Funny thing about me is that I can't stop until everything works better than it's ever supposed to.
In theory at least.

 

[Lazy JW]

...Am I thinking just a bit too hard about how my engine is put together?

Yup.

 

[Thad]

So what's the problem finding hyd roller lifters?
Crane pn X 1293-2

How many Ford engines used the same lifter as the 300? IIRC SBF and 385 series BBF And of those which later got factory hyd roller lifters? Difference between those engines and the 300? Spacing between lifter bores. So to retro fit/ use factory hyd roller lifters needs only to fab correct length tie bar and come up with some little spring thingie to retain tie bar in place.

Or do I over simplify?

 

[Alvor315]

I wasn't able to find the part you provided, but if they are the tie rod lifters, then they won't fit in the numbers 1 and 12 lifter valleys, because those valleys only fit 1 lifter each.

If they're the dog bone style lifters, then it would be difficult to bolt the dog bone retainer to the side of the lifter valley of 1 and 12 and on that note, I haven't seen any dog bone retainers that come in single installations. They have all been dog bones to hold down two lifters side by side.

Seems 1 and 12 are just a pain in the @$$.

 

[Gord]

Just a smidge more than a bit.

 

[Alvor315]

How about roller cam bearings too?
Variable valve timing?
Turbo charger?
Flex fuel tech?
ABS?
All wheel drive?

I'm on a roll now, can't stop thinkin'. I can guarantee that if the first four physically have room, they will be on the next engine I put in the car. Including the roller lifters I already mentioned. I already have a new block that I'm cleaning up. I'm saving for the new head now. By the time I'm done with my '60 bird it will be a modern car. And there's nothing you can do to stop me.

ABS is all over the place, it shouldn't be too hard to find a nice little system. I'll bet with a little tranny hump modification you can fit the Getrag 6mtl650 under the chassis.

8) Just a smudge more than a bit.

 

[Lazy JW]

With enough Cubic Dollars anything is possible
Have fun and post pictures.
Joe