The need to breathe

[Hank22]

Those of you who have installed breather boxes, where did you install the fittings on the valve covers?

Thanks

[IowaRedManx]

The valve covers on my Manx have threaded ports for the barbed fittings. I got them from Bugpack about 13 years ago

[slalombuggy]

I don't, and may others don't either. If you vent a valve cover only vent the 1/2 side. Internal pressure is built up in the case, not in the heads so venting the case is far more effective. If you care running an electric fuel pump run a hose from the block off plate to the box as well as one on the tower, if not run as large of a breather hose as you can off the tower.

brad

[Hank22]

why just the 1/2 side?

[vwracerdave]

Some believe, some don't. Install the vents on the valve cover as high as possible and as far front as possible.
_________________
2017 Street Comp Champion - Thunder Valley Raceway Park - Noble, OK
2010 Sportsman ET Champion - Mid-America Dragway - Arkansas City, KS
1997 Sportsman ET Champion - Thunder Valley Raceway Park - Noble ,OK
Featured in Dec. 2001 HOT VW's Magazine page 63

Watch my racing video's http://www.youtube.com/user/okvwracer/videos

[manxdavid]

Not needed, they're just another source of a possible leak. If your engine's making that much back pressure you've got problems that need a proper fix, not just a Band Aid. Just stick to the stock style VW breather vented the air filter(s).

[MrGoodtunes]

[Hank22]

originally the motor had two nipples on the filler tube and two connections on the air filter. the connections on the air filter impeded the engine cover from closing. I did not want to change to a shorter filter. so at this time I have those two hoses connected from the filler tube to the breather box and the third connection at the breather box plugged.

I am intrigued by MrGoodtune's set up as I am in Arizona where the temps compete with Florida

[manxdavid]

All a breather box will do is fill up with oil vapour then leak, unless you get the air filter to draw the fumes away.

[vwracerdave]

mrgoodtunes, no offense but your entire system is not accomplishing what you think it is. It's just a mass of unnecessary hoses. The #3 exhaust valve runs hot because of the aftermarket fan shroud that does not cool properly.
_________________
2017 Street Comp Champion - Thunder Valley Raceway Park - Noble, OK
2010 Sportsman ET Champion - Mid-America Dragway - Arkansas City, KS
1997 Sportsman ET Champion - Thunder Valley Raceway Park - Noble ,OK
Featured in Dec. 2001 HOT VW's Magazine page 63

Watch my racing video's http://www.youtube.com/user/okvwracer/videos

[MrGoodtunes]

Good point @vwracerdave, and no offense taken, but... While the aftermarket shroud has no quide fins inside, consider that there's no oil cooler radiator in there (it's external), additionally consider that the fan in there is the wide one for use with doghouse. These positives sort of conpensate for alleg'd negatives. Plus, I have a temperature sensor in place of #3's spark plug gasket sending to a meter I keep an eye on. The only time it ever goes above 300°F is sustain'd highway driving over 60 mph. It will get to the "danger" level of 350° under stress from mountain climbing or hard headwinds. I believe it's due to complications with getting good cool air into the fan from the scoop I glass'd into my buggy's side.

Driving through Michigan in a snow storm once, traffic going slow, temperature surprizingly hit 350°. Found the scoop all cram'd up with snow! In any case, the bottom line is that this engine build has been running well for nearly a quarter of a century, versus about half a dozen previous builds that I've burn'd to death in the past.

[rugblaster]

I think a breather is a good idea on a performance motor. Probably not needed on a stock or near stock engine. To think the heads can't vent case pressure you would have to believe the eight pushrod tubes don't connect the heads to the case. It makes no sense.

The best way I have found to do it is to connect both valve covers and the tower to a pan evacuation device in the header collector.......Google "Pan Evacuation System".........kits are available from Moroso or Milodon. Glue your valve covers gaskets on the covers with 3M trim cement or it will suck the gaskets into the heads. The idea is to create a vacuum in the case.....it will help with all kinds of amazing things.

Also, use Total Seal 2nd piston rings.
_________________
'69 Karmy, '69 Camper, Meyers clone, '65 drag bug, 10.78 @ 128 (sold it) '51 Dodge farm truck,
'09 MB E350 '18 MB E400, '65 Plymouth Valiant convertible and a '19 Ford F250 King Ranch (nicer, but dirty, farm truck)

VWoA factory trained line tech 75 till 90 or so
ASE Master Certification
VWoA Assoc. of Quality Technicians inductee (One of 25 in the five state southwest region)
La Confrerie des Chevaliers du Tastevin (San Angelo Chapter)
TCU ......GO FROGS!!!!!!

[didget69]

... I wonder what Gene Berg would say.

bnc
_________________
I never found the need to impress people with any mechanic certifications, trophies or track wins... unless it was for Mom to post on the refrigerator door.

[joescoolcustoms]

A worn stock engine can get by with stock venting. But as cylinder bores go up in size, crank stroke gets longer and cylinder pressures build with aftermarket cams, more venting is needed. For the science on that, just research any good race engine builders like Sonny's, Reher-Morrison and the like.

In '14 I built a 2165 cc engine with CR of 8.6:1. I drove it across the US coast to coast in my buggy. The entire time I was fighting my vent system. Anytime we cruised on the interstate and I was running over about 2900 RPM, the vent system started puking oil and misted it all over whoever was following and all over the back of the buggy. Puked about 4 quarts in 6000 miles.

My vent system was set up with the forward top edge of each VC vented, the stock oil fill vented, and the fuel pump block off vented. All of these vents ran up on top of the fan shroud to a custom breather tank with about 1 quart capacity and was filled loosely with stainless steel kitchen scrub pads, (machined curls of metal to help catch oil droplets as the vented air passed by) and has two large filters on top.

Once back home and disgusted with it, I did a lot of research and had previously read about muffler mike having a similar issue on his drag engines, and how he solved it. I found it again and made the same alterations to my engine.

http://www.thesamba.com/vw/forum/viewtopic.php?t=566237

http://www.mufflermike.com/news2000.html

The only alteration I made was to the Driver side VC, 3-4 side. Removed the vent and installed a drain instead. The drain is on the rear bottom of the VC and drains back to the front D-side of the sump. The left VC was filling up with oil do to the windage coming off of the crankshaft, and as cylinder pressure increased, (going closer to wide open throttle), the internal pressure was pushing the oil up the left side vent into the top mounted breather tank, and long extended runs on the interstate, filling the breather tank spilling out.

On my trip across the US in '15 at 7000 miles, and again to Alaska in '16 at 8000 miles, not one problem with the venting system. No problem with internal pressures and great performance. Coming on 37,000 miles on this engine and after the alteration at 7000 miles, it is a sweet runner.

_________________
Bad News Racing 2018 NORRA 1000 3rd in Class
Best Day Ever Racing 2022 NORRA 1000 2nd in Class and first All Female team to complete the race

Everyone is gifted. Some just do not open the package.

Looks like it was painted with a live chicken,polished with a brick and buffed with a pine cone

[vwracerdave]

The left valve cover fills with oil because the main oil passage is in the left side of the case and the 3/4 rocker arm get a lot more oil then the 1/2 side. The crank rotation does not force oil up the push rod tubes and is not the problem like everybody thinks. The correct solution to solve the 3/4 valve cover filling with oil is the Bob Hoover modifications.
_________________
2017 Street Comp Champion - Thunder Valley Raceway Park - Noble, OK
2010 Sportsman ET Champion - Mid-America Dragway - Arkansas City, KS
1997 Sportsman ET Champion - Thunder Valley Raceway Park - Noble ,OK
Featured in Dec. 2001 HOT VW's Magazine page 63

Watch my racing video's http://www.youtube.com/user/okvwracer/videos

[Hank22]

I googled Bob Hoover and found his blog But I could not find this modification,
any hints to find it?

[vwracerdave]

http://bobhooversblog.blogspot.ca/2007/05/hvx-mods.html
_________________
2017 Street Comp Champion - Thunder Valley Raceway Park - Noble, OK
2010 Sportsman ET Champion - Mid-America Dragway - Arkansas City, KS
1997 Sportsman ET Champion - Thunder Valley Raceway Park - Noble ,OK
Featured in Dec. 2001 HOT VW's Magazine page 63

Watch my racing video's http://www.youtube.com/user/okvwracer/videos

[joescoolcustoms]

[rugblaster]

I will add one thing. Hoover's theory has a fatal flaw. The lifter bore has oil pressure inside the bore at all times. Just because the oil hole in the lifter is not lined up with the oil galley doesn't mean the grooves in the lifter bodies don't have oil pressure, they do.

It would be like stating the crankshaft journals only have oil pressure when the hole in the crank lines up with the hole in the bearing.......totally ridiculous.
_________________
'69 Karmy, '69 Camper, Meyers clone, '65 drag bug, 10.78 @ 128 (sold it) '51 Dodge farm truck,
'09 MB E350 '18 MB E400, '65 Plymouth Valiant convertible and a '19 Ford F250 King Ranch (nicer, but dirty, farm truck)

VWoA factory trained line tech 75 till 90 or so
ASE Master Certification
VWoA Assoc. of Quality Technicians inductee (One of 25 in the five state southwest region)
La Confrerie des Chevaliers du Tastevin (San Angelo Chapter)
TCU ......GO FROGS!!!!!!

[MrGoodtunes]

Did a little test: Pull'd the hose off a valve cover nipple while engine was running. Found quite a bit more vapor pressure coming out from valve cover nipple than from fan shroud hose.