ATK High Performance 350ci TBI engine for 1988-1995 Trucks from Jegs

Erik the Awful

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Starts taking the engine down and finds it's the most Frankenstein grab bag of miscellaneous mix and match parts that it's not even funny.
It's amazing how little it takes to have a good-running engine, and also amazing at how some people can dork it up.

I may order a flat tappet cam for now... I am not worried if I only get 30k miles out of it.
The issue with a flat-tappet cam is that you might get 0 miles out of it. Cam failure during break-in is a serious concern.
 

Hipster

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Sometimes opening one up is like opening a can of worms. No point in putting a cam into an engine that's thought to already be tired.
 

1997

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Did you call S&J see if they have any recommendations?

I'm kinda in the same boat, i suspect the 95's cam has lost some of it's already low lift.
Back in the day, SBC were know for being tough on cam lobes.
Would like to go roller but the options are expensive .....
 

Schurkey

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I would worry about it coming apart. The metal contamination can ruin every machined surface in that engine.
Hydraulic lifters are like miniature oil filters. The passage into the lifter is huge in comparison to the metal dust and sludge in the oil. But the passage for oil leaving the lifter is microscopic. Crap gets in...can't get out.

Would like to go roller but the options are expensive .....
Options are dirt cheap...if you're prepared to install a stock, used roller cam and used roller lifters. Buy a core roller-cam block, steal the cam, lifters, dogbones, spider, cam thrust plate/bolts, pushrods, and timing set. That's essentially what I did, a few years ago. Pulled the lifters apart ONE AT A TIME for cleaning. Even re-used the timing chain 'n' sprockets.

Maybe you find a broken-crank engine to steal the valvetrain out of for $50. I paid $300, I think...but I used the block, crank, rods, and seven of the pistons, too. I did need different pushrods, as I'm not using self-aligning rockers and stock pushrods will be destroyed by pushrod guideplates.
 

Donald Mitchell

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I'm not looking for an argument, but hydraulic lifters were used successfully for more years than most of you have been around. Oh, and I remember the look on my friends face when one of his rollers ate a cam lobe.
 

1997

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Hydraulic lifters are like miniature oil filters. The passage into the lifter is huge in comparison to the metal dust and sludge in the oil. But the passage for oil leaving the lifter is microscopic. Crap gets in...can't get out.


Options are dirt cheap...if you're prepared to install a stock, used roller cam and used roller lifters. Buy a core roller-cam block, steal the cam, lifters, dogbones, spider, cam thrust plate/bolts, pushrods, and timing set. That's essentially what I did, a few years ago. Pulled the lifters apart ONE AT A TIME for cleaning. Even re-used the timing chain 'n' sprockets.

Maybe you find a broken-crank engine to steal the valvetrain out of for $50. I paid $300, I think...but I used the block, crank, rods, and seven of the pistons, too. I did need different pushrods, as I'm not using self-aligning rockers and stock pushrods will be destroyed by pushrod guideplates.

wish i had that option, unfortunately, pretty much no inventory where i am.
i'm envious of the posts of "treasure yard" finds, haha.
Autowreckers around are terrible and definitely not cheap.
only real option would be a vortec parts truck (probably high mileage), which brings it's own challenges.
 

someotherguy

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I'm not looking for an argument, but hydraulic lifters were used successfully for more years than most of you have been around. Oh, and I remember the look on my friends face when one of his rollers ate a cam lobe.
Sure, but today's oil formulations lack the ZDDP that valvetrains depended on in the non-roller days. Can't be contaminating those catalytic converters.

Nobody said roller valvetrains are perfect. They're superior to flat tappet in many ways, but you can still fall victim to defective parts. All of the "big three" are no strangers to valvetrain failures, in big numbers, across a wide variety of modern engines.

Richard
 

L31MaxExpress

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Sure, but today's oil formulations lack the ZDDP that valvetrains depended on in the non-roller days. Can't be contaminating those catalytic converters.

Nobody said roller valvetrains are perfect. They're superior to flat tappet in many ways, but you can still fall victim to defective parts. All of the "big three" are no strangers to valvetrain failures, in big numbers, across a wide variety of modern engines.

Richard

Lack of ZDDP does not seem to bother my Imports. Also most of the TBI trucks had the GM hard faced lifters. I cannot say that I have ever seen a flat tappet lifter or cam failure with those lifters.
 

someotherguy

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Lack of ZDDP does not seem to bother my Imports. Also most of the TBI trucks had the GM hard faced lifters. I cannot say that I have ever seen a flat tappet lifter or cam failure with those lifters.
It was a response to the broad-strokes statement of "I'm not looking for an argument, but hydraulic lifters were used successfully for more years than most of you have been around. Oh, and I remember the look on my friends face when one of his rollers ate a cam lobe." He didn't specifically say "flat tappet" but then the opposing argument of a single example of a roller lifter failure seemed to imply it. Either way it was weak bait and I shouldn't have bothered.

Richard
 
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