Cam plate oil hole for timing chain?

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QuickDart360

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Ok folks have a little confusion. I am about to install cam thrust retaining plate. Some members here habe suggested to leave passenger side upper bolt out to lube chain. However, I have a chrysler manual where it shows when smallblocks came with drilled bolt to put it on drivers side. So is there a reason to do opposite side instead.:eek:
 
Ok folks have a little confusion. I am about to install cam thrust retaining plate. Some members here habe suggested to leave passenger side upper bolt out to lube chain. However, I have a chrysler manual where it shows when smallblocks came with drilled bolt to put it on drivers side. So is there a reason to do opposite side instead.:eek:

You can either leave that bolt out, or use the bolt with the hole...

As long as the hole is open and able to let oil get to the timing chain...


If you have the drip tab for oiling, it requires leaving the bottom driver's side bolt out for the locating tab... I would not recommend not having the other bolt left out, but use the bolt with the hole in it as I wouldn't trust only 2 bolts to hold the camshaft thrust plate...
 
My 273 didn't have a drilled bolt but I drilled the plate and a tiny hole in the oil galley plug. You can see it in the upper left.

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You can either leave that bolt out, or use the bolt with the hole...

As long as the hole is open and able to let oil get to the timing chain...


If you have the drip tab for oiling, it requires leaving the bottom driver's side bolt out for the locating tab... I would not recommend not having the other bolt left out, but use the bolt with the hole in it as I wouldn't trust only 2 bolts to hold the camshaft thrust plate...
Ok but is the bolt with the hole on driver's side as manual says? Right side bot hole is closer to dripper tip as I observe it.
 
No leaks from the front cover or seal.
 
It confused me because the manual I have is an original manual from chrysler! It is red white and blue in color on front cover and is for 1975 chrysler chassis/engine. It shows a clear pic of bolt with hole on drivers side. However, I see how it makes more sense to put bolt with hole on left (looking @ motor from front side.) Since oil will come down to oil slinger tab as a direct or more direct shot than other side.
 
Leave the bolt with the hole in it on the bench. You can drill a small hole in the plate on either side. That bolt is worthless.

If you want to be really cool, you can tap the plate and screw a .032ish air bleed in there. I know people don't really like drilling holes smaller that .125 and that's just too big. That's how I do my stuff. I screw an air bleed into the plate from the gallery side.
 
If you don't have a bolt with a hole in it, you can drill one thru, if you have a drill press, and a drill press vice. Just center punch the center of the bolt head, and drill it out with a 1/8th in, or smaller drill bit. Oil the bit as you drill. Then deburr the holes.
I just drilled one yesterday. Came out great. Easy peasey.
Install your newly drilled bolt in the upper left bolt hole, on the front (pass side) of your engine.
Dave
 
I have the thrust plate with the tab on it I thought I had lost the 4th bolt and looked even for it just to realize that the "4th" hole was for the tab and didnt have a bolt in it. Lol
I like tmm oil plug hole that seems like it would be the most effective and easiest. Bolts can be a right pain to drill thru and I'm with krazykuda I dont trust just two bolts. I think I will do the oil plug hole!!
Just curious does the factory original system not provide enough oil to the timing chain? Is that the purpose for this? Or is it just a more is better type deal?
 
More is better. That’s the idea behind it. It’s a nice and helpful easy mod I can help in very high performance engines.
 
Not building what most would consider high performance but wth I may as well do it while its apart. I have an el cheapo timing chain maybe the extra oil will hold it together.
 
I have the thrust plate with the tab on it I thought I had lost the 4th bolt and looked even for it just to realize that the "4th" hole was for the tab and didnt have a bolt in it. Lol
I like tmm oil plug hole that seems like it would be the most effective and easiest. Bolts can be a right pain to drill thru and I'm with krazykuda I dont trust just two bolts. I think I will do the oil plug hole!!
Just curious does the factory original system not provide enough oil to the timing chain? Is that the purpose for this? Or is it just a more is better type deal?

You need to get oil to the chain through that bolt hole or by TMM's method to drill a small hole in the galley plug... Keep in mind that the cup plug hole has PRESSURIZED oil feed and the "factory" bolt hole is just drain and no pressure...

Once you get oil in the front of the engine from either hole, then the oil slinger can sling it over the chain to lube it...
 
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I can't see where a pin hole in a non pressurized bolt would flow a lot of oil. I left the upper passenger side bolt out since I didn't have a dripper. If you want to go the dripper route I'm sure and A bodied bud would have one to sell!

upload_2019-4-13_9-11-42.jpeg
 
a hole into the oil galley- a small hole- also bleeds foam and trapped air bubbles
nothing wrong with the drain hole either as an addition
 
I was on one of my hang outs a few days ago and the discussion was about timing chains. I may have seen something like this here, too.

Anywho... the discussion was double row vs. single row timing chains. There were several guys in the business who install single row timing chains on competition engines ie. drag and oval track stuff that is routinely rebuilt. The concensus was single row is fine... but double row sells. The single row seens to require a bit less power to spin it, too.

Looking back almost 60 years I never installed a double row timing chain in any engine until I did my blown Hemi back around 2005. They were not available for most of that time. And I did a bunch of engines of different flavors... SBC, SBF, FE Fords, 351-C Fords, Olds, Pontiac, Buick and Mopar.

Has anyone ever seen a single row chain with iron sprockets fail? I mean in under 7-8,000 rpm applications...

Right now a $29.00 single row chain with cast sprockets seems to be pretty enticing.
 
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