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Rocker Arm Failure

I cannot imagine how the push rod would get like that if the rocker let loose first for simply being to old. I'm not onboard with the old age arguement. Flat tappet cam or roller?
 
I cannot imagine how the push rod would get like that if the rocker let loose first for simply being to old. I'm not onboard with the old age arguement. Flat tappet cam or roller?
That was the bent pushrod next to the one that got destroyed, which is weird,
 
IMO, the Pic has all the hallmarks of an extended timeframe Lubrication related failure.

Off topic....
but why 1.6's ?

Is the Camshaft lobe profile you selected designed to optimize faster ramps/lift ?
or,
targeting a strictly a "lift" @ Flow/rpm benefit ?

If you don't mind me inquiring how big is the engine under the Tf240's ?
 
E
IMO, the Pic has all the hallmarks of an extended timeframe Lubrication related failure.

Off topic....
but why 1.6's ?

Is the Camshaft lobe profile you selected designed to optimize faster ramps/lift ?
or,
targeting a strictly a "lift" @ Flow/rpm benefit ?
I'm also curious, everyone seems to be using 1.6 rockers.
I wonder about piston to valve clearance, and it seems like more stress on components.
 
IMO, the Pic has all the hallmarks of an extended timeframe Lubrication related failure.

Off topic....
but why 1.6's ?

Is the Camshaft lobe profile you selected designed to optimize faster ramps/lift ?
or,
targeting a strictly a "lift" @ Flow/rpm benefit ?

If you don't mind me inquiring how big is the engine under the Tf240's ?
I do not mind at all, The group here are awesome and want to help as usual. I have a Hughes/Howards F/T Solid that takes advantage of .904 lifters it's 242 /246 and with 1.6 around .600 lift. It's a 451 "B" engine. Makes acceptable vacuum for PB and really nice in the mid and really loves high gear keeps pulling till about 6200, Very pleased with Perf. I wonder if I would be better off/ for valvetrain stability with 1.5 and would I be giving up a bunch. Car has been on track 79 Magnum with 3.54 runs 11:60's @ 118 consistently so it's fun car LOL!!! and comfortable
 
I do not mind at all, The group here are awesome and want to help as usual. I have a Hughes/Howards F/T Solid that takes advantage of .904 lifters it's 242 /246 and with 1.6 around .600 lift. It's a 451 "B" engine. Makes acceptable vacuum for PB and really nice in the mid and really loves high gear keeps pulling till about 6200, Very pleased with Perf. I wonder if I would be better off/ for valvetrain stability with 1.5 and would I be giving up a bunch. Car has been on track 79 Magnum with 3.54 runs 11:60's @ 118 consistently so it's fun car LOL!!! and comfortable

Thx for that info.
The dedicated .904" profiles are indeed already utilizing the larger Lifter Diameter load carrying capabilities to get to higher Lifts sooner than their comparable Chev .842" and Ford .875" brethren...
but as far as I know those profiles are calculated/targeted to get there on 1.5 ratios ? and are already running elevated V/Spring Pressures(150# +seat) and rates to remain stable ?
Yours isn't pushing the envelope as hard as others are... .600" Lift with 1.6 ratio on a 242 pattern isn't 'extreme' as some others... but it's quicker than most any .842 I've seen.
No matter...
sounds like everything Lifter and Lobe-wise is happy with patent run in..... and now running well on the 1.6's so good for you ! You are far braver than I am on today's Oils.
That said,
It sounds like those poor old CRANE's may have lived a very full life long before they ever got re-utilized in that dedicated .904 Lifter environment ?
Aluminum work hardens.... maybe they were flexing severely before cratering ?

In this tough parts environment.... I don't think you'd lose much if anything going to 1.5's if that's all you can find ?
Might even see higher/lower Ft/Lbs Torque translate to a quicker 60 ft short times = lower ET ?
Stranger stuff has happened LOL
If you see quicker 60 fts don't be afraid to drop shift rpm's until you see the ET's come back or drop as well ?
 
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Can anyone tell me what ratio the following "Mopar .904" lobes are designed for?
0927211255.jpg
 
You might be aware but the mancini rockers made by harlan sharp have bushings. Never had the hughes. I wish T&d were affordable.

The MRE/HS set I bought a few months ago are not bushed (MRE57001-15-714K). Straight aluminum on steel shaft.

Chuck
 
So Basically the only 1.6 Steel rocker is PRW or RSA which RSA doesn't have any in stock. Comp has steel arms but in 1.5 ratio, Too bad there isn't any other choice. Tons of Aluminum but no Steel
 
Like 33 IMP said, "I wonder if the pushrod "escaped."" Might want to check your valve springs also, for peace of mind.
 
It broke the exhaust rocker. Cylinder pressure had no where to go. Excess load when the intake started to open. Result ; bent intake pushrod.
Doug
 
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