Low Cost Camshaft Options - Need Opinions

[Schurkey]

I have seen non-roller blocks with so much wear that the cam actually scores the rear block plug

Yes. There are occasional issues with the non-thrust-plate blocks--ESPECIALLY when using a thrust button that hasn't been properly clearanced--where the timing gear digs into the iron of the block, gouging the block and screwing-up the fore/aft placement of the cam.

This looks REALLY bad when the block is pulled apart for rebuilding.

However, any decent machine shop can cut the gouged metal out, and press-in a bigass hard valve seat insert large enough to go around the cam bearing. The insert is machined to match the face of the block, if needed (but if the machinist does his measuring and cutting properly, there'd be little need.)

Once there's a huge valve seat insert in there, just TRY to wear-out that section of the block again.

Another method--preventative rather than restorative--is to drill a tiny hole from the front of the block into an oil gallery, so that pressurized oil is squirted onto the back-side of the cam gear thrust surface.

You must be registered for see images attach

This "shouldn't" be needed, because that surface is already lubed by the oil bleeding out of the front of the front cam bearing. OTOH, a little more can't hurt.

 

[Hipster]

Yes. There are occasional issues with the non-thrust-plate blocks--ESPECIALLY when using a thrust button that hasn't been properly clearanced--where the timing gear digs into the iron of the block, gouging the block and screwing-up the fore/aft placement of the cam.

This looks REALLY bad when the block is pulled apart for rebuilding.

However, any decent machine shop can cut the gouged metal out, and press-in a bigass hard valve seat insert large enough to go around the cam bearing. The insert is machined to match the face of the block, if needed (but if the machinist does his measuring and cutting properly, there'd be little need.)

Once there's a huge valve seat insert in there, just TRY to wear-out that section of the block again.

Another method--preventative rather than restorative--is to drill a tiny hole from the front of the block into an oil gallery, so that pressurized oil is squirted onto the back-side of the cam gear thrust surface.

You must be registered for see images attach

This "shouldn't" be needed, because that surface is already lubed by the oil bleeding out of the front of the front cam bearing. OTOH, a little more can't hurt.

It was a one time deal I ran into, cam was too far back causing lifter /cam alignment issues., the machinist's solution was to machine clearance for a thrust bearing on the block side and drill a oil galley plug to feed/splash the back of the cam gear to provide better oiling, never an issue. It worked for a street engine. I see what you posted this as a similar but better fix. I was looking at far more damage than drilling a hole could conpensate for. Lots of oil mods can be done pre-emptively, after the fact not so much after the damage has been done.

 

[Majoraslayer]

To revist the second part of my question, would an LT1 block use different thrust plate mounting bolts than my truck block? My block's a roller block obviously as there are holes for the plate mounting bolts and bosses for the lifter spider, but the thrust plate bolts I borrowed out of my LT1 bottom out long before the thrust plate is tight on my truck block. If they're supposed to be the same bolts that work in both blocks, I'm curious if those holes aren't fully drilled and tapped on my block. They do use different thrust retainer plates (my block uses a much wider plate than the LT1), but Summit and other sites all seem to list part number 14093637 that supposedly works in a multitude of blocks.

 

[Hipster]

To revist the second part of my question, would an LT1 block use different thrust plate mounting bolts than my truck block? My block's a roller block obviously as there are holes for the plate mounting bolts and bosses for the lifter spider, but the thrust plate bolts I borrowed out of my LT1 bottom out long before the thrust plate is tight on my truck block. If they're supposed to be the same bolts that work in both blocks, I'm curious if those holes aren't fully drilled and tapped on my block. They do use different thrust retainer plates (my block uses a much wider plate than the LT1), but Summit and other sites all seem to list part number 14093637 that supposedly works in a multitude of blocks.

If you got both blocks there not understanding why you don't have access, or a means to measure. To my knowledge L31 max is one of the most notable members familiar with the differences. Schurkey on his game too. You want to mix and match not up to everyone else to do your legwork.

 

[Majoraslayer]

Wow, you're just full of criticism today lol

This is my first engine build, forgive me for seeking help.

 

[Schurkey]

Drilling the oil gallery plug is often described as a way to oil the timing chain. In truth, it's done by the factories to rapidly bleed air from the gallery at startup, so it doesn't have to push through the lifters, causing noisy lifters.

The oil sprayed out of the oil gallery plug would be flung outward by the cam gear--it wouldn't help with lubing the cam-gear-to-block interface.

To revist the second part of my question, would an LT1 block use different thrust plate mounting bolts than my truck block?

No idea. Measure your bolt hole depth, cut the screws down to fit. Or buy shorter screws. Be careful with the head size--if the head sticks up too far it might interfere with the cam gear. Kinda thinking the original screws are button-head.

See post 16 for photos.

 

[Hipster]

Drilling the oil gallery plug is often described as a way to oil the timing chain. In truth, it's done by the factories to rapidly bleed air from the gallery at startup, so it doesn't have to push through the lifters, causing noisy lifters.

More about the abundance of oil and splash effect than little oil with no bleed from no hole.