1966 poly 318 2bbl car engine, how does the chain get oiled? This car will be stock and driven a lot in summer.

The top right bolt hole for cam plate is a blind hole and all bolts are solid, no oil hole bolt like what mopar performance sells for LA engines.

No oil trough in there like the photo from 1978 service manual . Also the 1978 manual shows the cam plate has a oil slot in it. Should any upgrade be done or put it together in stock form?

Don’t know why the photo is upside down, sorry.

on my LA engine the passenger side top cam retainer bolt passes through to the valley. That is the one that should have a hole in the bolt. I think the idea is that the oil drips out from that hole and runs onto the tab and onto the chain. I know I forgot to put a drilled bolt in there and ran no oil slinger and my chain was smoked in 5000 miles. I just recently put it back together and corrected those issues.

oil drips from the 2 large holes that open to the lifter valley. You can drill an 1/8" hole in the upper pass cam plate bolt for extra oiling (duplicating OE). For the nth degree you could drill a .015" (1/64 drill bit) hole in the pass front horizontle oil gallery mini freeze plug (best would be to tap for a pipe plug (alum) & drill it then a 3/8 hole in the cam plate for that oil to squirt past. #1 get a good quality chain set

Hmmm, my R1 block doesn't have those holes, I had never noticed that.

It'd be getting splash up from the pan. On a side note if ever doing the .015" mod be sure to use a shallow or thin the pipe plug so that you do not block oil hole just inside the front block face that goes down & oils the #1 journal/drivers side oil gallery.

I though of drilling the end plug of the valley, just wondered what others have had success with.

Both top bolt holes are blind, no oil going to come from there without modifications. The bottom bolt holes go through to the crankcase area.

Those 2 large holes to the valley are not at the bottom of the valley so how much oil will pass through there at 2500-2800 RPM on the freeway driving? I would imagine that’s why they put those holes there. I also think that’s why they added the drip trough in the late 70’s, it didn’t oil the chain very well.

Yeah it might be the other top one (where Ma had the drilled bolt) if we are on the same page, its been quite awhile since I did my last one. I drilled the bolt & the .015" mod. EDIT "top" (right bolt hole) I meant to say lower. I checked my 408 bare block today & it is the lower pass cam plate bolt hole that goes thru to oil. The lower drivers hole is blind

I would think that front cam bearing would bleed 1/2 of it's oil to the inside and 1/2 toward the timing chain also

And don't forget the bottom sprocket is exposed to the sump with oil flailing around everywhere.

On the early Poly and early HEMI blocks the oil is pumped up from the front crank journal bearing passage to the front cam bearing along the way 1/2 branches off to the main lifter gallery, the other 1/2 feeds the front cam bearing which oils/drips onto the lower timing gear and the oil slings on the chain/upper gear from there, unlike the LA series (67-up) smblks where the lifter gallery passage oils the chain/gears with an orifice bolt and oil tab