Boss 429 broken roller lifter

Looking for suggestions?
I broke a solid roller lifter in my Boss 429 several weeks ago, and have been trying to decide what I want to do to put it back together. The car is mostly street driven.

Here are some of the basic engine specs: A460 block, 4.560 bore 4.3 stroke (562 CI), 6.8 rod, 10.25 compression, Kaase heads, 258/264 @ .050 .718 lift, standard needle bearing .875 lifter diameter.

Number 6 intake lifter failed. Looks like the wheel quit rolling and formed a flat spot and then cracked from the heat. It was in 4 pieces in the bottom of the pan. The other 15 lifters appear fine.

Looking for comments or suggestions? Go to a .903 lifter (bigger wheel)? Switch to a bushing lifter? Change brands (there are only 3 companies I know that make Z-Bar lifters)? Do Moral or Jesel make a Z-Bar lifters? Switch to hydraulic roller? Does a hydraulic roller in the Boss 429 also require a Z-Bar? Who makes them? and are any available in a larger diameter then .875?

Thanks.

Craig

cfb289 wrote:Looking for suggestions?
I broke a solid roller lifter in my Boss 429 several weeks ago, and have been trying to decide what I want to do to put it back together.  The car is mostly street driven.

Here are some of the basic engine specs: A460 block, 4.560 bore 4.3 stroke (562 CI), 6.8 rod, 10.25 compression, Kaase heads, 258/264 @ .050 .718 lift, standard needle bearing .875 lifter diameter.

Number 6 intake lifter failed.  Looks like the wheel quit rolling and formed a flat spot and then cracked from the heat.  It was in 4 pieces in the bottom of the pan.  The other 15 lifters appear fine.

Looking for comments or suggestions?  Go to a .903 lifter (bigger wheel)?  Switch to a bushing lifter?  Change brands (there are only 3 companies I know that make Z-Bar lifters)?  Do Moral or Jesel make a Z-Bar lifters?  Switch to hydraulic roller?  Does a hydraulic roller in the Boss 429 also require a Z-Bar?  Who makes them? and are any available in a larger diameter then .875?

Thanks.

Craig

lash too loose, Or too soft of springs will do this, We run comps with needles for years at a time, still never a problem

Don't switch to a hyd roller.

not cracked from the heat Ill bet, but cracked from the cam hitting it as the spring was tryin to push it back to the cam

Rich has actually seem my car, and would probably agree that there is nothing typical or ordinary about a full tube chassis stretched wheel base 71 Pinto, with a 562 Inch Boss 429 in it. I just went back and looked it was finished in 2011, so has been together for 5 years (hard for me to believe it has been that long). One thing I didn't do was write down the mileage when I put the Boss engine in, but it has to be between 3000 and 5000 miles on it now.

Our shop has been open since the early 70's but this is the only Boss 429 we have ever built, so I was hoping to gain some knowledge on what has worked for others, who may have built a few more of these than I have.

I thought that I remembered a post from several years ago, that hydraulic rollers could be problematic in a BBF, but that the higher pushrod seat was actually beneficial in the Boss engine (better pushrod angle). If a hydraulic roller in the Boss doesn't require a Z-Bar lifter then Isky makes a bushed hydraulic roller lifter for the BBF rated to 7500 rpm. Might be worth a try.

Back to a solid roller, Crower, Crane, and Comp are the only 3 companies that I know of that offer a Z-Bar lifter for the Boss engine. Crower is the only one who's catalog shows a larger diameter .903 lifter, with a .810 wheel. They also offer bushed lifters now. So in theory a Crower bushed .903 lifter should be the best lifter offered for the Boss engine. Unless someone else offers something that isn't listed in their catalog.

Craig

Lash was kept at .010 cold (which = .018 Intake and .020 exhaust hot). When I took it apart the other 15 lifters where still at .010 cold. On the broken one, lash adjuster was still torqued, rocker shaft to head was torqued, pushrod is still straight. Obviously I didn't check the lash often enough to catch this one before it failed.

Valve spring pressure was 250 on the seat, 590 open.

Craig

Sounds like it was simply that particular lifter that failed, perhaps the fracture point was lower than on the rest.
But I think you found your answer in the Crower bushed lifter with the larger wheel.
They are very strong, you cant go wrong with Crower stuff!!

Were these  Comp lifters?

I switched to Crower bushing lifters awhile back and feel theyre a wise choice for any large street driven solid roller.

No they where not Comp.  They are Crower with the high pressure oiling to the needles.  I pressed the axle out of the other lifter of the pair.  Every thing looks good.  I can see which side of the axle was down and had the load on it, put can't pickup any difference with a mic.  If there is any wear it is less than .0001

I have exchanged several PMs with Rich about the possibility of not enough oil.  Block restrictors, Pass Front .063, Pass Rear .028, Driver Front .020 (to oil the distributor gear).  Every lifter has a .030 hole feeding the needles, and a .080 hole feeding the pushrod.  The .080 feed hole is open to the lifter oil galley for about half the lifter travel, at about half the travel it gets reduced to a .015 slot.

Craig

In my opinion you need to open up the oil to the valve train. These days I'm putting 1/16" at the front and rear even on drag race only engines with A460 blocks.

More oil or less oil leakage/loss? Do we really need an .080 oil feed to every pushrod?

Craig

This .080" hole....is it the edge orifice of the lifter, a hole in a lifter bore bushing or what?

My block does not current have any lifter bushings in it. It is an oil hole straight in the side of the lifter, which feeds the pushrod seat. There is also a .015 slot from the lifter oil band up to this oil hole. When placed in the block with the red dots facing the center as Crower's instructions state. The .080 hole is open to the lifter oil galley, until about half the cam lift. Then the hole gets covered up by the lifter bore, but still gets fed oil from the .015 slot to the oil band.

The Kaase pushrods have a .085 hole through them.

If the intake and exhaust lifter were swapped, and the red dots were facing the out side of the block, the .080 hole would be covered by the lifter bore all the time, but would be continuously fed oil by the .015 slot to the oil band. Should be the same as running a .015 restrictor in all the pushrods. This would eliminate a lot of oil loss through the pushrods and rockers, leaving more oil for the roller needles. The question is .015 enough oil to keep from burning up pushrod ends, and rockers?

Craig

The lifter edge orifice should be on the same side as the tie bars. The tie bars should be turned toward the center of the engine.

Boss 429 Z-bar lifter. Intake the bar faces the outside of the block, Exhaust the bar faces the center of the block. The 2 lifters are drilled differently. The pushrod oil feed hole on both of them faces the lifter oil galley (the outside of the block). The oil feed hole is perpendicular to the center line of the block.

Craig

Zbar...got it. At any rate the edge orifice / feed hole should not be turned into the oil gallery. Some of comps stuff has the holes 90* from the gallery....crower/crane/morel are turned 180* from the gallery toward the center of engine.

Refer to the pictures below:

The first picture shows the red dots which they tell you to face to the center of the block.  The oil hole visible is just a bind hole .090 deep, it doesn't go anywhere.

The second picture shows the other side which faces the outside of the block and the lifter oil galley.  See the white wires I put through the oil feed to the pushrod. Just below the white wire is the .015 slot from the oil band to the .080 feed hole.

The Third picture shows the #6 pair.  The intake is the one that broke.  The exhaust I pressed apart to look at the axle and needles.

what did you end up doing with your lifters?crower will redo your liters with bushings,cheaper than new ones.
also you don't want the .080 lifter hole in the oil galley,it will fill the valve covers pretty quick.i know,i did that once on my 509 boss,and after a few minutes of run time the pressure would drop from 75 to 20.redid the lifters right and it was back to what it should be,and i had external drains on it as well.
love the car.do you street drive that?

Still working on it. I talked to Crower, Isky, Jesel, Kaase, and Straub Technologies at the PRI show in early December. It's funny was talking to two guys from Crower, and one said stick with the needle bearings, and the the other said no go with the bushing lifters. They each had different reasons for their suggestions. Kaase, said I'm not the only one to have this problem, and that he didn't think it was lack of oil. Final decision right or wrong, is that I'm going to try a new .903 diameter Morel hydraulic roller lifter. They are suppose to be good to about 800 lbs open pressure, and can be run on solid roller cam profiles. The new cam from Straub and lifters should ship this week.

Yes the car is driven on the street, 5000 miles on it when the lifter failed.

Cheers.
Craig

So, what kind of load are the springs you have?

250 lbs on the seat, 590 lbs open.

Craig

I thought I would post this up just to help clarify for any newbies on here to better understand what everyone is discussing. I took a screen grab of the Ford blueprint that shows a cross section of a lifter bore and erased a bunch of clutter. Then colored in the oil passages (red), lifter bore (green).