Just FYI
There is a different between blow by and a car smoking out of the rear tail pipe. It is not uncommon for a motor that has a ton of miles/hours on it to have both issues but the two are not necessarily connected.

Blow by is a cause buy gases passing your compression rings. Smoke out of the tail pipe is caused by too much oil getting past the oiling rings. As cylinder wear and become bigger and out of round both of these thinks can occur. I have seen brand new cars look like an old school locomotives when you remove the oil cap. and I have seen new engine that would oil foul the plugs in about 50 miles. Most of the time this was because they used the wrong rings or a burr kept the ring from spring open after install.

Performance type motor tend to see higher cylinder pressures than normal engines, for that reason many builders build in extra ring gap and they will use rings that are not as tight and that will "wear in" quickly. As a general rule engines built with performance in mind tend to have more blow by. You can put your oil under a microscope and look as the size of the carbon deposits that are getting past your rings and from there figure if the motor needs some internal attention. You can also send your oil out and have it tested and if the carbon deposits are a problem the lab will let you know.

In my opinion PCV valves are emission items. I do not want to put that already burnt now dirty gases back in my race engine. Before PCV valve car makers used a draft tube. It is like your filter but it would use the speed of the car to suck out the gases. Just search Draft tube crank case ventilation. I ran these on all my race engines. All my daily cars get PVC system. So, it depends on what you want. I am not a big fan of just using filters in the valve overs because that is just letting all that crap just sit in the motor. Your filters are work backwards keeping all the crap in your motor not out. If you do this you should change you oil more often even if you run synthetic. Of course if you only drive the car 1000 miles a year then none of it matters.

 

Hi there @Everett#2390

Sorry to bother you guys again. I cannot find any GM EOS online or any shops in the UK. In some searches I noticed it was discontinued ?

When I go to Halfords etc they are not sure of the supplements they have in the shelves will suit older classic engines.

I see other products online like “Shine Armor”,
”Rislone”, “Moly”,
and “Wynns oil treatment”, “Slick oil treatment”.

Any recommendation ? I am lost.

Thanks in advance.

 

i know its an old post, but sometime when you have time, do a compression check and look for a low cyl. just to insure that whomever put the rings in did so correctly (not lined up gaps) also the big block will have s o m e blowby all the time. but not that you would notice. the breather caps are good idea, but in previous post take notice of what the deff of blow by is. its somewhat common and not something you want, especially in the excess. i missed a gear once and blew the breather out of the valve cover with blow by. (it survived) but motor had no blowby before or after. so just 2 cents worth.

 

@mikess68

Thank you Sir!

 

That's not blowby that's crankcase pressure that exceeded the venting capacity,blowby is when combustion gets past the rings into the crankcase and sends smoke out the vents.Blowby bad,crankcase pressure normal,big blocks have a lot of crankcase pressure so when you really wind them up it needs someplace to go.