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-   -   Swapped PCV & gained big time! (https://67-72chevytrucks.com/vboard/showthread.php?t=787630)

SunSoaked 05-27-2019 11:59 PM

Swapped PCV & gained big time!
 
3 Attachment(s)
Ok, so I've finally got my 350 Vortec running great. The one thing I had been putting off was swapping the Wagner dual stage pcv. Today, I got r done.
With engine warmed up at idle I had 15 inches of vacuum and a very slight lope.
Then I swapped valves and t'd in the purge line from the charcoal cannister.
Started engine and adjusted valve per instructions.
The idle went up 300 rpm. I adjusted it back down.
It idles extremely smooth and I lost the lope I had. It now idles with 19 perfectly steady inches of vacuum and has noticeably better throttle response.
These aren't cheap, but worth every penny IMO.

geezer#99 05-28-2019 12:23 AM

Re: Swapped PCV & gained big time!
 
Good info!
And here’s a link to it if others are interested.

http://mewagner.com/?p=444

weq92f 05-28-2019 12:43 PM

Re: Swapped PCV & gained big time!
 
.
That's a cool idea...

These guys like it too:

https://www.hemmings.com/blog/article/let-it-out/

-klb

cashforclunkers 05-28-2019 01:40 PM

Re: Swapped PCV & gained big time!
 
Good stuff. Never knew. I will be keeping this in mind. Thanks

hjewell2 05-28-2019 08:35 PM

Re: Swapped PCV & gained big time!
 
Thank you for the post on this , wanted to try one but the price stopped me not knowing if this was snake oil. Now I will pay the money knowing it works according to your write up.

Tom 05-29-2019 04:30 PM

Re: Swapped PCV & gained big time!
 
I've never even heard of custom PCV valves, heck never even thought about it before.

AcampoDave 05-29-2019 07:22 PM

Re: Swapped PCV & gained big time!
 
Be careful, last time a guy claimed he gained big time from one of those, the poor guy got shot down big time. http://67-72chevytrucks.com/vboard/s...d.php?t=630891 Edit: after reading all the info on the website, I ended up shelling out for one too.

SunSoaked 05-29-2019 11:06 PM

Re: Swapped PCV & gained big time!
 
Ya, I'm not gonna make any claims in improved gas mileage.
I'll leave the logic behind it's design and function to thier website. It convinced me to try it. As I said, it smoothed out my idle, gained 5 inches of vacuum and improved throttle response. My simple mind thinks of the pcv as a big vacuum leak sucking in contaminated air. Being able to restrict it at idle and open it up during cruise when the engine is creating more vapor makes sense to me.

mattfranklin 05-30-2019 11:04 AM

Re: Swapped PCV & gained big time!
 
Interesting. I'll have to read up on what they're doing.

tdangle 05-30-2019 12:02 PM

Re: Swapped PCV & gained big time!
 
Wonder, would eliminating the PCV valve also increase idle vacuum?

weq92f 05-30-2019 02:03 PM

Re: Swapped PCV & gained big time!
 
Quote:

Originally Posted by tdangle (Post 8534029)
Wonder, would eliminating the PCV valve also increase idle vacuum?

Well... it depends...

The PCV valve is supposed to restrict air flow under high vacuum ( idle ) conditions down to something small enough not to affect idle quality. That is, the controlled vacuum leak that is the PCV system is supposed to go away at idle.

If the PCV valve you have currently isn't doing that, then you have too large a vacuum "leak" at idle as a result, which will cause the things that vacuum leaks cause!

Easy enough to check. Before I recently replaced my non-functioning-properly PCV valve, plugging the vacuum line to it caused idle to clean up very nicely ( just as if a vacuum leak had been plugged ) and likely did increase overall Hg as well!

-klb

tdangle 05-30-2019 03:34 PM

Re: Swapped PCV & gained big time!
 
Quote:

Originally Posted by weq92f (Post 8534090)
Well... it depends...

The PCV valve is supposed to restrict air flow under high vacuum ( idle ) conditions down to something small enough not to affect idle quality. That is, the controlled vacuum leak that is the PCV system is supposed to go away at idle.

If the PCV valve you have currently isn't doing that, then you have too large a vacuum "leak" at idle as a result, which will cause the things that vacuum leaks cause!

Easy enough to check. Before I recently replaced my non-functioning-properly PCV valve, plugging the vacuum line to it caused idle to clean up very nicely ( just as if a vacuum leak had been plugged ) and likely did increase overall Hg as well!

-klb

It just hit me how the dumb thing works! Always wondered how and was always told shake it. If it rattles it's OK. Now I understand at high vac such as cruise or idle the weight (or what ever it is) pulls up and pretty much closes off the sucking from the engine/valve cover. At lower vac levels the weight drops and the engine can pull vapors from the engine. What a simple design!

SunSoaked 05-31-2019 11:29 AM

Re: Swapped PCV & gained big time!
 
You got it. Keep in mind that the factory engine produces a specific amount of vacuum therefore the factory makes a pcv specific to that engine. When you alter the engine with a cam, timing, carb, etc the pcv is no longer matched to the engine characteristics. This is the beauty of the Wagner valve. You can adjust to function in harmony with any engine. It should be the last pcv you ever buy.

AcampoDave 06-15-2019 12:01 PM

Re: Swapped PCV & gained big time!
 
Ok so here's what i gained on my '64 longbed with a mainly stock '61 283 with the street breather previously converted to a PCV. The vacum went from 19hg to 20hg and the idle increased by 200 rpm. After restoring the original idle rpm, the motor ran smoothly and seemed to have a cleaner idle. It wasnt easy tuning the valve due to it's location on my engine but it was doable. I had to use extra caution to prevent the valve or the allen wrench from slipping thru my fingers and falling behind the engine. (Allen wrench still did, thankfully it didn't drop down the pcv hole.) Would I do it again? Sure. In fact I'm gonna, as soon as i get my '66 back on the road. It's 283 has been moddified a bit with the usual stuff so we'll see how much difference it makes on that one in a month or two.

SunSoaked 06-16-2019 08:08 PM

Re: Swapped PCV & gained big time!
 
Quote:

Originally Posted by AcampoDave (Post 8542722)
Ok so here's what i gained on my '64 longbed with a mainly stock '61 283 with the street breather previously converted to a PCV. The vacum went from 19hg to 20hg and the idle increased by 200 rpm. After restoring the original idle rpm, the motor ran smoothly and seemed to have a cleaner idle. It wasnt easy tuning the valve due to it's location on my engine but it was doable. I had to use extra caution to prevent the valve or the allen wrench from slipping thru my fingers and falling behind the engine. (Allen wrench still did, thankfully it didn't drop down the pcv hole.) Would I do it again? Sure. In fact I'm gonna, as soon as i get my '66 back on the road. It's 283 has been moddified a bit with the usual stuff so we'll see how much difference it makes on that one in a month or two.

Two thumbs up!! I don't regret spending the $ one bit.

toolboxchev 06-17-2019 02:11 PM

Re: Swapped PCV & gained big time!
 
Wondering if anyone is using this product with an older style gen 1 block and how they configured it?

Appreciate the responses!

SunSoaked 06-17-2019 02:35 PM

Re: Swapped PCV & gained big time!
 
Breather on one side, pcv in the other. Boom done.

RodnRudy 06-17-2019 06:11 PM

Re: Swapped PCV & gained big time!
 
1 Attachment(s)
After reading this post I ordered one of the adjustable Wagner pcv valves and installed it on my Gen 1 350. Watched the video half a dozen times and followed the directions. It smoothed out the idle just like it's supposed to. I also had a problem with oily residue accumulating around the carb at the vacuum port. I'll monitor that and adjust the valve if needed.

SunSoaked 06-17-2019 11:07 PM

Re: Swapped PCV & gained big time!
 
Nice. That's a good looking engine. I love those valve covers.

MySons68C20 06-19-2019 04:51 PM

Re: Swapped PCV & gained big time!
 
I just ordered one of these and will share my before and after.
Thank you.
Blake

bosephus 06-23-2019 08:12 PM

Re: Swapped PCV & gained big time!
 
Per their website,they offer a 25% discount for a group buy of 8 or more units.

kelz702 10-03-2019 06:37 PM

Re: Swapped PCV & gained big time!
 
1 Attachment(s)
I've been thinking about ordering one of their PCV valves for awhile now. I'm glad I found this post. I've been having a hard time getting my truck to idle correctly. I bought a dress up pcv valve from Summit awhile back when I had the motor built and im pretty sure its what's been giving me issues. The QuickFuel carburetor doesn't seem to have the adjustability that it should have. Is anyone else interested in buying one at the group rate with the 25% off discount? It looks like we only need 8 people

geezer#99 10-03-2019 06:52 PM

Re: Swapped PCV & gained big time!
 
Quote:

Originally Posted by kelz702 (Post 8603460)
I've been thinking about ordering one of their PCV valves for awhile now. I'm glad I found this post. I've been having a hard time getting my truck to idle correctly. I bought a dress up pcv valve from Summit awhile back when I had the motor built and im pretty sure its what's been giving me issues. The QuickFuel carburetor doesn't seem to have the adjustability that it should have. Is anyone else interested in buying one at the group rate with the 25% off discount? It looks like we only need 8 people

I see a 4 corner idle on your carb.
Which quickfuel is it?

kelz702 10-03-2019 06:59 PM

Re: Swapped PCV & gained big time!
 
Quote:

Originally Posted by geezer#99 (Post 8603475)
I see a 4 corner idle on your carb.
Which quickfuel is it?

It's a Quickfuel HR-650 Hot Rod Series with Mechanical secondary

geezer#99 10-03-2019 07:17 PM

Re: Swapped PCV & gained big time!
 
People have been having idle problems with a bunch of quickfuel carbs.
Maybe you’ll find some info here on a 670.

https://www.hotrodders.com/forum/hol...ix-507033.html

What do you run for timing?
Initial?
Mechanical?
Vac advance numbers?


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