The Cal-look Lounge

Id like to hear from "around the globe" some trials and tribulations with breather box capacity vs. motor combo/size. I am blue printing our new motor and I always like to hear some stories on what has worked the best and worst. I have used a few different set ups, but its always nice to hear from the creative minds of the fellow vw community.  ;) :D

http://www.thesamba.com/vw/classifieds/detail.php?id=462643

I use this one, very nice. A bit too mirror-like finish for me, but nothing 240 grit paper couldn´t fix.
http://www.csp-shop.de/shop2/frame_nachladen.php?func=det&wkid=69947714290&rub1=Engine&rub2=Breather+Boxes&artnr=13816a&pn=0

another

http://www.thesamba.com/vw/classifieds/detail.php?id=693462

This picture is my favorite breather box picture.... Straight to the point... venting where the excess pressure really is...
Would be interesting to know if Håkan is venting the valve covers too?

I found that the routing of breather hoses was very important. My little 1600 revved to around 6000rpm and had breather pipes from the rocker covers and the oil filler and fuel pump block offs. The various pipes were joined by T-pieces into one line and then went to a breather box made from an old fire extinguisher (nice little aluminium bottle between the decklid hinges!). Used that same arrangement with my 2180 and got a weep from one rocker cover, then with the 2276 it got worse. Both revved to about 7400rpm. We worked out that the one rocker cover was becoming pressurised by the route of the breathers at high RPM - made another box with four "in"s and one "out" with a little K&N filter.

Has anyone truly found out the functionability and reasoniing behinding venting the valve covers to the sump? Other than draining oil due to gravity, I dont see how this would be a huge beneft if the covers are already venting to a breather box? Or am I am I completely wrong and someone has a smart answer for me? ??? :P ;)

     Well from my understanding the benefit of drain back lines to the sump is to keep supply up. Depending on what heads and covers you use there might be as much as 2 or 3 qts. in the valve covers alone. There is a video by Muffler Mike somewhere showing a windowed valve cover filling up at around 6000rpm. so when you factor in your oil lines,filter, oil passages, push rod tubes, valve covers, probably even breather lines and possibly even breather box, thats alot of oil not in the sump at high rpm. Mike Lawless did a how to and a very good explanation story in a past Hot V.W.'s issue but I don't remember which one.

I have a hard time recognizing the benefit..., there are already four drain back tubes into the engine case, one more makes a huge difference...?
Muffler Mikes video is interesting... it shows that the oil doesn't want to leave the valve covers... could it be related to pressure differences?

Good points here guys. I have a 1914 making 140hp and all I have for a venting system is the standard hoses to the valve covers and one hose to the bung on stock oil filler. My breather box is a cheapo aluminum box. It can hold 1/4qts. max I would say. I regularly zing my engine to 6k+ rpms and have never experienced any blowby, misting on engine, etc. I do not have a sand seal behind my berg pulley.
 
A race engine with higher compression that makes more horsepower and torque probably changes the equation significantly. Why is this though? Is there one aspect that changes everything or is it an increase in demand on the entire system?

  by the four drain back lines do you mean the pushrod tubes? not sure there, if so they would theoretically be full of oil if the valve covers are to. I'm not saying I'm an advocate of this Eric just brought it up and I'm trying to explain what I understand of it. Whichever HOT V.W.'s issue it is that has the story from MIke Lawless is much more informitive as to the theories and or facts of this modificaton. I don't do this nor does the S/G car I crew chief for but I know alot of people do run them.  I think the pressures inside the case has a great deal with keeping the oil in the covers. In thinking about it myself I presume there is possibility of the pump creating a vaccum drawing the oil from the drain back lines. Also I've seen guys run 2 drain backs per head.

Yes I do.
If those four are full of oil, the new "lower" one will be filled to... and the same pressure difference would be acting on this new one, even if it was below the oil "level"
I understand where your comming from, and I must get hold of this story...
Yes I do to, Muffler Mikes theory says that this filling comes from the rotation of the crank and obviously from lubing the rockers... I believe in this to but I think the reason for the oil not returning is that we vent the covers... why would the oil leave low pressure conditions to go back in to the high pressure area? If gravity is not enough...

Actually, setting up a engine in a Spintron machine could give an answer to this pretty easy, if you had a window in the rocker cover. The spintron can spin the engine at 7000 without it actually running (electric motor). In this case the blow by pressure would not be present in the case... would the oil run back in to the case then??

The best solution to all this is a full on dry sump... but I dont want to go there yet... :)

actually the push rod tubes would be above the sump and pickup the drain backs go down to the sump "behind" the oil being sucked by the pump hence a possible draw by the pump. For what it's worth this is not my area of expertise and the mag write up is where the info is.

I've tried a lot of different combinations to keep oil where it belongs, and the HVWs article that Jason so kindly mentioned is close to being the culmination of that. A race motor, because of the oil being pumped into and slung off of the crankshaft at high RPM creates a big vortex of oil that is being slammed into the 3-4 rocker box thru the pushrod tubes that are supposed to allow drainback. This is what a big drain line running to the sump below the windage helps...but ONLY if the top of the case is vented and not the valve covers. If you vent the valve covers, don't bother with the drain lines because the oil will take the path of least resistance....up the breather line and into the breather box and NOT into the sump. If the top of the case is vented, the case becomes a lower pressure area than the VCs and the oil will be forced under pressure back to the sump....where it belongs. Currently I have a single #10 breather line from the oil fill tower which is baffled. The line goes into the bottom of a baffled 2 quart tank. There are no vents on the VCs. I have scavenge lines going from the bottom of the head to the small stage of an autocraft stage a half oil pump.

Lots of opinions out there about what works. I can tell you my motor now stays bone dry on the outside and my bearings are always nearly perfect on teardown after 60 or more runs at 8500rpm with a 14-1 CR because the oil stays where it belongs. So listen to the opinions, make your decision and observe the results. You'll eventually find something that works for you.

great info Mike thanks.

im still not sure I buy the wave of oil off the crank shaft.

OK Taylor. That's good. Since I've known you for a quite a few years, I know that you are much smarter and much more motivated than many. Do your own research. One place to start is to look into some V8 style oil pans the NHRA Comp and Super Stock guys use. They have built in scrapers and a kick-out on the left side to redirect the oil back into the sump.

Doing your own research and coming up with your own answers is a good thing. Hopefully by doing so you might come up with something we haven't tried, which after all is the point of us all discussing this.

You are talking my language here now, this is exactly what my thoughts have circled around... pressure differences. When you vent in the VC much of the blow by pulses will travel up the push rod tubes... fat chance any oil drains back that way... would be like pissing against the wind  :o
Next spring my venting will be done in the Generator stand... only!

Any pics of your solution mr. Lawless?

lots of good stuff here  :D

Here's a shot of the external arrangement as of now at the top of the page. Scroll to the bottom and you can see from the earlier shot that the fill tower has grown to contain some baffling and the single hose to the breather box is all there is. Inquiring mind may want to know where the hose from the top of the breather tank goes....

http://home.comcast.net/~mlawless29/hardware.html

I do!!

Next time I see you, you should have a drive in my car. It still sports the original engine (closing in on 122k miles), with a couple performance mods. You can take that car around any left hand corner as fast as you please, and the oil pressure wont hardly budge. Do the same on a right hander, and the oil pressure plummets!! Why? Because the crankshaft is fighting the oil "slosh" on left turns, and doing the exact opposite on right handers.

Definitely agree with Mike Lawless and others that oil is being flung off the crank and
up the pushrod tubes into left cylinder head rocker chamber.

A lot of racers consider it normal to empty their puke tank after each pass. In some
cases this will be due to poor ring seal and excessive blowby but case windage and/or
inadequate breather design are certainly an issue.

Few years ago Engine Machine Service ran an engine on their dyno with a windowed rocker
cover to see what's happening at high rpm. Muffler Mike posted the video on his site. You
can clearly see the rocker cover fill with oil. You don't see the same effect on the 1-2
head. I've seen exactly the same thing here.

The longer the stroke, the higher the rpm, the greater the problem.
If you're sat on the outside edge of a crank counterweight and spinning at 8000rpm, 88mm
stroke crank has you covering more distance in the same time than you would on a 69mm
i.e.  you're travelling faster

I've seen internal case pics of cranks at high speed. Engine oil is literally wrapped and
twisted around the crank like a thick rope.

In the likes of Nascar, Pro Stock and other high end engine categories the engine builder
will go to great lengths to reduce the amount of oil that is flung around inside the
block by incorporating baffles, screens, scrapers, custom shaped oil pans, trap doors etc
etc..... i.e. whatever they can do to take oil off and away from the crank.

Dry sumping the engine is the ultimate way to go but a well designed dry sump system will
still include various tricks and modifications to divert and control oil travel.

In a wet sump motor most important thing is to ensure there's an adequate supply of oil
at the oil pickup pipe. The aim should be to collect and divert all oil coming off the
crank (having lubed the mains and big ends) away from rotating parts and straight back to
the sump.

I'm not sure it's even possible to squeeze in a set of oil scrapers like the V8 guys use
because of the upside down crank/cam orientation used in the VW. I've looked for a way
but haven't found one yet!

Popular approach nowadays, as mentioned in this thread, is to accept the fact oil gets
thrown into the left head and alleviate the problem by adding a drainback facility. This
obviously helps reduce the amount of oil hanging around in places it serves no purpose.
Some even block the oil holes in the 3-4 head pushrods to further reduce the amount of
oil going to that side of the motor.

When a crank beats and whips up hot oil at 8000rpm it makes a nice job of turning it into
froth... you're trying to lubricate your motor with fizzy oil.

Ever seen race engine's rod bearings with an alligator skin appearance? I believe that's
cavitation erosion - inadequate lubrication caused by pumping aerated oil through the
system. You want a ready supply of non-aerated oil available at the pickup at all times
i.e you don't want the crank to whisk/beat the shit out of the oil!
Harder to cool aerated oil too!

I've been looking at this problem for a while and have gradually been incorporating a few
internal case mods with a view to reducing the problem - especially for high rpm, long
stroke engines.

Part of the problem is the basic flat four engine design.... the boxer engine is
inherently well balanced.... for each piston/rod movement, there is an equal and opposite
deal happening on the other side. Now take a look at the case design. It effectively
seals off one case half from the other, with 1 & 3 operating in one half and 2 & 4 in the
other. When 1 & 3 are heading down to BDC, 2 & 4 are on their way up.

I recall reading somewhere this is one of the reasons Ferrari dropped their boxer race
engine... the design had advantages in terms of balance but internal windage was always
an issue. Switching to a V config was also more compact so windage wasn't the only factor
but it's significant they cited it as a problem.

F1 engines and other mega buck stuff deliberately compartmentalise pairs of opposing cylinders.
Each compartment is individually scavenged of oil by its own dry sump scavenge section.
In V configuration the paired cylinders don't have the disadvantage of operating in boxer
mode.

Back to the VW.... when a pair of pistons (say 1 & 3) are on their way down they have to
displace air somewhere. At the same time 2 & 4 are on the way up, making room for that
displaced air. So you have a continual high speed exchange of air taking place between
the front and back halves of the case. The path of least resistance (most space for the
air to make its move) is down by the cam. At high engine speeds I believe this super
rapid and turbulent air exchange is creating havoc with oil return to the sump.
Amount of air displacement increases with bore and stroke.

My mods are aimed at equalizing pressure between the front and rear case halves in
an attempt to reduce the storm to a breeze.

Also thought about trying the rocker drain idea but figured it might be better to
minimise the amount of oil getting up there in the first place. Have to be careful not to
limit drainback through the pushrod tubes. Sort of like a one way system.

First engine I tried some of this stuff was an 88mm stroke race engine - an ideal candidate to experiment
on. Normally an engine of this type will puke some oil out the rocker cover breathers at
high speed, especially on the 3-4 head. For the dyno tests I fitted a pair of stock
rocker covers with 1/2" ID breather hose connected. Both hoses were routed into separate
drain pans.

First wide open throttle pull I was hoping the mods would result in a reduction in the
amount of oil out the 3-4 rocker breather compared to what I've seen before. The pan was
bone dry! I used the same breather setup for the whole test session, including runs on
nitrous. The drain pans stayed dry throughout.

Testing on the dyno can't replicate oil movement that takes place due to launch,
acceleration, braking etc so was keen to hear feedback from the owner's experience at the
track.... he reports very minimal amount of oil deposited in the catch tank.

This is a work in progress so no detailed pics of the mods yet but it all starts to make
sense if you study the internal layout of the case, picture what's going on re piston
movement, figure how you can keep oil away from the crank and cam etc etc

Mentioned blowby/ring seal at the start.... this is improved by equalizing internal case
pressure and reducing windage. Reduce pressure below the piston by say 1 psi, that's 1
psi less the downward travelling piston has to overcome on the combustion stroke i.e.
better ring seal and more power at the flywheel

Fantastic stuff here John, can't wait to see your pictures as I am sure they will be very helpful to others. 8) Matt

Is there where the "and a half" comes in? :)

So to add to this thread even more, I haven’t read much on capacity of the breather box itself. What is the recommended capacity ratio per engine specifications? For the motor I am currently working on right now, I am leaning towards a 2 quart breather, but I’d also like to read some insight on the appropriate capacity of the breather for the application it is being used for. Anyone? ;) ;D

Take a look @ where the breather comes off of on a 911 (any of them) or even one of the old 4 cam 4 cylinders.
The pistons coming down from TDC oppose one another in a VW, so yes you're asking these two comlumns of air under those 94mm piston undersides (parachute shaped!) to ram into one another, and like JM said, with longer stroke it gets worse...here is another reason.
My friend found the aftermarket alum cases were even worse when it came to windage. Reason he found was webbing was so heavy and bulky in case that it was creating air dams! On mag VW cases, I round the main webbings off with sanding cartridges, to help present an easier path to those columns of air. Porsche did this in the 901/20 motors in 1965 and found 10hp just by this mod alone.
It isn't just ring seal that causes the froth-storm... though that has A LOT to do with it. Before I re-did the race motor at my old job (not sure who built it previous to me) it had horrible windage problems, and became the butt of many oil down jokes. Upon taking it down, I found the compression rings were obviously shot, and ring gap was wide open, and you could see where corners of 1st and 2nd rings were rounded off. New rings, manicured webs in VW case and attention to oil level sure made a world of difference, as the car now left the track dry for the next guy.
I run a small, maybe .5 liter box my friend fabbed for me and stock VW 12mm hose from stock filler and covers. I regularly run my car up to 7000 (street car) and it isn't puking itself all over.
I think ideally, fabbing a take off directly off case (on race motor where no shroud is used) would be ultimate in solving the two columns of air fighting each other
see ya guys
Jim

If one consider the path the air have to navigate to get to the timing gear "chamber", and then up the generator stand it makes sense to vent in the roof abow 2&4 AND 1&3... but I'm not so sure its smart to make holes there in a mag case.

And in a typ 4 case??

Michael

There is definitely more of an internal venting problem with the aluminum cases. Most builders have found it necessary to do quite a bit of deburring as Mr Ratto pointed out. The port going thru to the timing box can be almost completely closed off with casting flash and the spigot windows need work too. For the most part, that is all one can do in a practical sense. Anything that can be done to enhance the return flow back to the sump is a good thing to do.

To answer the breather box size question... on a race car, while a small size would might work in most cases, the ruling actually calls for a quart minimum. Common courtesy dictates more. It's better to err on the side of preventing oil spillage IMO, and keeping our fellow racers safe from driving through anything that could easily be prevented.

what about just welding 1/2" or even 3//8" bungs into top of case, one above the 1/3 chamber and one above 2/4 chamber, run AN8 or whatever 1/2" or 12mm hoses to puke box
Would it jeopardize the strength of the case, do you guys think?

Just to clarify... these do abselutely nothing, correct?
(http://www.cbperformance.com/catalogimages/1760.jpg)

This has turned into a very good post! I would also like to see some solutions on oil leaking out of the crank pulley when the motor is at high RPM's for extended periods of time... Preferably not a sand seal!

I wouldn't use one...

When I was building engines at Limited Edition in the late '80s, the boss decided each engine spec was to include a windage tray (same as in pic).
Often wondered what he thought when they later moved premises and discovered approx 30 brand new windage trays hidden behind the lathe  ;D

Sure they'll help prevent oil in the sump getting picked up by the whirlwind going on around the crank but any oil being flung off the crank bounces off the tray right back into the storm.
It's also a hindrance to the oil's passage from crank to pickup tube.

You want to get the oil off and far away from the crank as quick as possible - cue dry sump tank  ;)
Alternatively a deep sump with necessary case mods, venting etc to make it easy for oil to get detached from the crank and deposited down below
i.e. the less oil being flung around inside the case the better

Not sure if anybody mentioned this yet but running too much oil causes problems and costs power...
many of my customers are surprised when I tell them set oil level so it's barely touching the bottom of the dipstick.


Most likely cause is one or more of the following: excessive blowby/inadequate case venting/poor quality pulley/too much oil
Plus all the other stuff I mentioned earlier  ;)

What is your definition of "too much oil" and in what circumstances do you use less oil than the factory marks on the dipstick? It make no sense to run less oil than is necessary if a lot of it is being flung around by the crank or sitting in the rocker box. I always have my oil level set at the top line of the dipstick. My engine has a 1.5 quart sump and a external filter. These accesories do not raise the level; they add capacity.

I like the simplicity of these, especially for a street car. But I'm guessing that they probably aren't any good, either ::)

(http://www.cbperformance.com/catalogimages/1745.jpg)
http://www.cbperformance.com/catalog.asp?ProductID=189

With a 356 gen pulley, I don't think fan speed would be sacrificed too much.

And I agree about setting the oil level low... on an engine with a deep sump, of course ;)

John is referring to race motors that see very high RPM. It's certain that an oil level close to stock is way to high for a drag motor. The oil vortex from the spinning crank with suck it up like a hurricane sucks up matter in its vortex. But you are correct that a street motor needs the extra oil and isn't hurt by a stock oil level. However, if you have a deep sump and are experiencing excess oil discharge out of the breather, try lowering the oil level a half quart and see if it helps. I would in no way advocate lowering the oil level without a deep sump.

These days, I don't even run a dipstick as it's just another leak path. I have a 4 quart sump and a filter and no oil cooler. I run 6 quarts of oil. As long as none leaks out, I don't need to worry about adding any. In theory, and assuming the case itself has a 2 1/2 quart capacity as a stocker, and adding in 1 quart for oil filter and oil lines, that should put my oil level 1 1/2 quarts below the top line of a dipstick. And for the record, yes. I have experimented to find a balance between having enough or too much oil.

Mike, what kind of rpm are you seeing on your race motor and what stroke crank do you run? Thanks

the motor sees close to 8500 at the shift, and around 8400 thru the traps. Stroke is 84.

At the PRA races where the car only needs to run 11.90, I back off on the shift rpm.

What is your definition of "too much oil" and in what circumstances do you use less oil than the factory marks on the dipstick? It make no sense to run less oil than is necessary if a lot of it is being flung around by the crank or sitting in the rocker box. I always have my oil level set at the top line of the dipstick. My engine has a 1.5 quart sump and a external filter. These accesories do not raise the level; they add capacity.
[/quote]

As Mike stated, you can not run on a “full tank” of oil. I learned that lesson with my ghia when I was at the full line on the dip stick and burned half the oil on my header when I spewed it out of the top of the breather at Carlsbad. I always run my oil level so it is just touching the tip of the dipstick. With those high rpms the oil is getting shot around way too much and cause it come out where you don’t want it…the track.

I ran into this problem again at last drag day. Oversight of a race motor vs. a street motor as we were racing my dad’s car. He still drives the car on the streets regularly and runs his oil level at the marked full notch on the dipstick. Nevertheless, after my pass in the car, his breather box was spewing oil faster than Kate Moss can upchuck a cheese burger. Luckily nothing hit the track ;)
 

For me the whole point of fitting a deep sump is to reduce oil LEVEL
You only need sufficient oil to ensure a constant supply at the pickup tube under all
driving conditions

There's no rule that states oil must be run to the top mark on the dipstick. On a stock
engine (no deep sump), the marks indicate factory recommended capacity. Fitting a deep
sump doesn't necessarily mean you must increase overall capacity by the equivalent extra
sump volume

Extreme example... if it were practical to fit a sump that extended downward to 1mm above
the road surface (maybe 10 quart?), I'd aim to run conservative capacity (3 to 4 quarts/litres)
but would have succeeded in dropping the LEVEL way below the crank. That would do all
sorts of good things for the engine. In the real world we have to be practical and take into
account ground clearance, potholes etc.

Drag racers can afford to go deeper and ideally keep all of the oil outside/below the crankcase

Some of the mods already discussed in this thread help reduce the amount of oil
pointlessly flying around inside the case (wrapped around the crank, stuffed up inside
the 3-4 rocker cover etc). If you can rely on that oil being efficiently returned to the
sump, you can afford to further reduce oil capacity, which has the added knock on effect of reducing oil level

For obvious reasons it's better to err on the cautious side, so my general (cautious) rule is...
1.5 quart sump - set to lower mark on dipstick
Larger sumps (3.5 & 4qt) - just touching the bottom of the stick
Never had a problem with that, street or strip

Droppping oil level from the top mark makes more power!
Seen it plenty of times on the dyno. If you have oil to the top mark and test the
motor at 6000rpm+ you generally see very aerated oil pumped out the breathers. Drop the
level, repeat the test and the puking stops... or at least reduces - depends on the
engine (oil mods, build quality, ring seal etc). Power gains may only be small but
happens due to the crank not getting as wrapped up in oil.
Which is easier.... running on land or in a swimming pool?

Anyone experimenting with even lower levels needs to make some oil
control/breather mods if they want to avoid sucking air and frying bearings.

Application has to be considered too.... a circuit car throws oil around in a different
manner to a drag car and has different requirements

Some of the mods people have discovered tend not to get shared, especially amongst the
circuit racers.... it probably cost them a few motors to find the tricks that work  ;)

Good info John, thanks for sharing!  :)

Valid points, John. I have a hot street car, whatever that means,:-) entirely different topic somewhere on this site. It is not necessary for me to squeeze every last horsepower out of my engine, so I will leave the oil level where it is.

I had a little talk with Håkan Lundgren the other day about his breather set up:
(http://cal-look.no/lounge/index.php?action=dlattach;topic=7304.0;attach=23352;image)
 As I thought he only vents the crank case, "as per Pauters instructions", he said...

That seals the deal for me... I'm drilling a hole ;D

This is a great topic!

Bumping this topic back up :). I have some questions. I'm in the process of building my very first engine. A nice 1915cc with IDA's. I want to do the following mods:

Vents
Fuel pump outlet
Generator stand

Sump
GB 3.5qt deep sump and lowering the oil level

Internal case mods
As John Mahers pics, exept for drilling the cam oil way. Should I mod #2 and #3 bearing saddles or only #2 when not drilling??


Does this sound ok to you guys? Motor will be street drivin and will see a blast up to 7000rpm.

Thanks!

I did only no. 2. Modyfying no. 3 bearing saddle doesn´t make sense without drilling the passageway.

How much wider is it? Also deeper? Did you use a dremel with a bit on it?

I stayed on the safe side with a dremel bit

before and after:

(http://lh5.ggpht.com/_nKjezkastzY/SZH903uUB5I/AAAAAAAAAKE/RBb5awAuiQ0/s720/DSC00417.JPG)

(http://lh4.ggpht.com/_nKjezkastzY/SZH92El2eBI/AAAAAAAAAKM/G3BHMX1NrEc/s720/DSC00418.JPG)

http://www.dremeleurope.com/dremelocs/modules/oragetblob.dll?db=dremelocs&item=dremelocs.items&id=3958,1754,16&mime=image/jpeg&maxwidth=266&maxheight=266

Very interesting Thread 8)

This is such a  great topic, is it a sticky?

Agree, There is risk with a small box, Bigger is better and it not like it's weight issue.

Jesse, I have done the same mods to my 2276 this summer. Except I have a 3 quart sump. No major internal modifications except removed most of the "hat" on the oil pickup.

No venting on the covers, small empi breather mounted on the firewall. Works great.

Hello.
So where did you connect your breather box then JS?

To the fuel pump block off and the oil filler. Drilled a 2nd hole in the front of the box and blocked the two on the sides.

Intressant,thanks.

  Interesting post the problem i am having is I build a 1776 CC with single port heads small cam and my compression is 8.1 with a stock carburetor for my stock 1964 VW and I had to pull the engine out 4 times because of an oil leak at the flywheel seal . So I replaced the flywheel after i had pulled the engine out twice. I have looked all around the case behind the flywheel and cannot see any type of cracks thinking it could be the problem all looks good. Is it possible that the crankcase pressure is allowing the oil to force its way out the seal. So i decided to install the fittings at the valve covers to let them breath if this will help I never encountered this on my other motors which are bigger and have the dual 48 IDA'S .

 Thanks
 Frenchy

  I am doing more research on this issue. Number one i did not smell to see if it was oil or transmission oil the reason was it was very thin oil so I had assume it was engine oil. I am thinking the transmission has much more pressure build up not because of the bigger size engine but possibly because the small vented hole on the nose cone could be clogged up from years of dirt build up around it. I also had a new pilot shaft installed so I know that part is OK . I will do all of these and let you all know if it was my main problem. Thanks
 

   Frenchy !!

Well the issue here was the nose cone vent hole is clogged up so i drilled a small hole on the inlet side plug to vent it out problem solved .

Frenchy

hello
 drilling a hole in the case, it's not dangerous for the case?

I recently installed a Vintage Speed breather tower with a vent hose from the stock fuel pump outlet and one open-air filter.  Now I have no oil leaks or spray, even on the drag strip at 8200 rpm.

(http://i67.tinypic.com/2m5e0ja.jpg)