Metric Hemi Catch Cans

[1978 NYB]

So.....i have discovered that the metric Hemi engines have a problem with blow by and is causing build up on the valves. I guess the fix is an aftermarket catch can that hooks in the PCV system and you drain it from time to time. So my question to the Metric Hemi owners here what catch can kit are you using? And is there any other Metric Hemi inherent problems I don't know about yet?

Graham, what is Chrysler's view on this issue?

 

[commando1]

 

[Dobalovr]

Bob I have one on my Magnum. After seeing the amount of oil vapour getting into the intake I had to have one. That said FCA has no issues having a catch can they just dont see the need. The crap in the can is unbelievable especially when it gets colder out and condensation contaminates the vapour and pools in the can. I use the Billet Technologies version. They are slow to ship but do the best work.

 

[1978 NYB]

Thanks Graham.

I'm going to order a kit from them today.

 

[1978 NYB]

View attachment 165123

It doesn't leak out.....

It trashes the inside of the throttle body and build up on the valves.

 

[jct]

Replace the pcv valve more often?

 

[Fratzog]

i have discovered that the metric Hemi engines have a problem with blow by and is causing build up on the valves.

Any idea what years are affected?

 

[Dobalovr]

Any idea what years are affected?

My Mag is a 2006 I have seen these on cars from 2005-2017 with either 3.5l or 5.7 Hemi. My throttle body was coated with a thin film of oil.

 

[1978 NYB]

Any idea what years are affected?

Gen 4 on the trucks 2009-2018.

Graham is probably the go to guy for this info.

 

[Dobalovr]

 

[dart4forte]

Replace the pcv valve more often?

Has nothing to do with the PCV. Those motors are built with low tension rings including the oil ring meaning there is less tension against the cylinder wall allowing for less friction and more power. Low tension rings have a been used in the racing engine community for years. Many old timer Stock and Superstock racers have experimented with the best ring combos and cylinder wall finishes getting the least amount of tension against the cylinder walls. Ive seen the tension on some motors on engine stands so light you can almost turn the crank by hand. Of course their results are highly kept secrets.

Older cars tend to have blow-by which is usually caused by cylinder and ring wear. All the ricecake cars have low tension rings in their motors. In order for the low tension rings to work the cylinder wall has a particular wall finish. This is issue is something the manufacturer probably knows about but will not admit to it in that it would become a warranty nightmare.

Difference between low-tension and ordinary piston rings

 

[1978 NYB]

I ordered a Billet Technologies catch can from Moe's Performance. They had it in stock and I'll have it from Texas on Thursday.

 

[1978 NYB]

I was talking to Matt at Moe's Performance and he said that they have a ton of guys with Gen 4 trucks that are running 12's in the 1/4 mile with a few bolt ons and a Diablo tuner. He also said they have a few trucks running in the 10's.He also said my stock truck will run mid 14's with the factory 3.92 axle that I have.

 

[1978 NYB]

 

[1978 NYB]

Check out the gunk in the bottom of the catch can at the 4:35 mark of the video.

 

[Wollfen]

I wonder if someone ran one of these on an old classic , would they get similar results?

 

[1978 NYB]

I wonder if someone ran one of these on an old classic , would they get similar results?

I would think so especially with older engines and the blow by that gets by the valve guides in big blocks.

 

[Wollfen]

I would think so especially with older engines and the blow by that gets by the valve guides in big blocks.

Hmmm, got my gears grinding now...