Better Breathing

[ozchips]

ok my old 54 austin has an su on it and a dirty big airfilter with about 3 turns between the actual filter and the neck of the su , it used to have a carby and an older style oil filled filter
what I wondering is would i get any benefit out of fitting a ramflow air filter directly to the su (like the ones on the minis)
and instead of running a breather hose to the filter , just put a seperate breather on top of the motor .
My thinking is , in my climate this will be a lot better as it is more air and cooler air , also getting rid of the breather hose will stop hot oily air going in ?
Will there be any benefit , or will there be problems ?

[Godzilla]

In my honest opinion No, i dont think your going to feel much diffrence..

A colder, denser air does aid horse power but in the case of an old motor i doubt you will notice much diffrence.

The oily air comming out of the breather (if theres lots of it due to worn rings) could be filtered via a oil catch can (about $70). You open it up and fill it with stainless steel wool to help seperate the oil from the air.

I have one like this setup on my GTR.

Venting this air to atmosphere is a no no, keep it hooked upto the air cleaner.

A larger more free flowing air cleaner helps but what id suggest is one with a larger surface area and not a small one that flows better.

Those small ones tend to have less filtering properties (larger holes that the dirt gets through).

A filter with a larger surface area will flow more and filter better.

Maybe a cold air box built around the air filter with a duct to pull cool air from outside may aid the cars breathing better.

[ozchips]

not particulary after an increase in hp , 10 is enough or 28 at 4300 rpm lmao
just when it is hotter it seems to be starved of air or not running very well
I thought of the mini , ie ramflow as the early mini motors are nearly identical
i can soak the ramflow filter in oil I am told for better filtration
I am just after a better setup than I have now ,which is not quite original for an su setup
all those other suggestions are good mate , and I appreciate them , but not an option at the moment
oh yeah there is not a lot of oily air coming form the breather , I just thought the engine would benefit from not having that hot air go in
unless it is actually bad for the car , I will look at doing it this way , mainly for the cost factor as the original gear is very hard to get hold off and also very pricey
So I need an alternative for improvement and long term cost

[Godzilla]

When driving a car down on power, the effects of hot air become most noticable in summer.

I drove the Ford today and its stinking hot here in Melbourne, the thing felt like 2 of the 6 cylinders were missing. Dead, no response, no getup and go.

Your only option 2 assit this effect is to duct in cooler air from outside, a cooler air is denser.

Ive seen this effect on dynos, lots of horsepower lost if the ambiant temp or altitude is high.

Some people even run their fuel through ice cans in race situations to help fight it.

There are many aftermarket filters made for su setups, yes you can assist the flow to fight it but remember your #1 aim is to keep the air clean comming into the engine.

If its good for a mini, its a good option for yours too, but remember when the air is hot, its thinner.

Nothing wrong with fitting aftermarket mini cleaners, anything that helps breathing is a good thing.

Just be carefull of oil soaked foam ones that can be difficult to place back into the steel mesh holders after a wash, they have a tendancy to fit poorly after a while and you can find a corner where they didnt fit properly letting dirty air straight in.

[Godzilla]

Looks good from far.


But far from good.


Just keep an eye on those foam ones, you think they are in right and working well but one little mistake after a wash and you can have an open corner.

Dont ask what HKS want for genuine replacement foams. LOL

[ozchips]

yup that is the type of thing , and also a seperate breather insead of a hose from motor to filter
mate my little a30 gets something done all the time , you can only expect that is a car 55 years old lol
if I seperate the air coming i the car and the breather then the ambient temp will still be below what is being pushed in form the motor , so all in all should be cool
I think I will do it
thanks for the advice , I really appreciate it
btw , just those little plug on breathers ok ?

[Godzilla]

Yep plug on breathers should be fine, its not under pressure.

I know for modern cars its illegal to vent the crankcase gasses to atmosphere but ill bet that yours factory or cars from that era did vent to atmosphere.

I remember Holden's and fords from the 50's and 60's did.

A different set of ADR rules apply to older cars such as yours and should be fine.

Edit; if your new cleaner body has a hole where the breather plug use to go in, you can buy a variaty of plugs from clark rubber to suit, just take your cleaner body in with you to match the plug to the hole.

[ozchips]

thanks mate , I was looking at the air filters at a specialists mini place and you can get them with or without the breather bit
$60 they cost , and new foam filters are around $0 , but still cheaper than trying to source the other original ones
and yes old car different set of rules
although compared to the holdens and fords of the 50's the austin was a pretty advanced car lol

[Godzilla]

Some thoughts about your breather filter come to mind that i want you to know.

The main point of this post is to discuss oil and your exhaust manifold = a engine bay fire.

Make sure your breather filter cannot get oil over the exhaust manifold.

Some old cars use to run breathers with baffles in them to help reduce oil getting over the motor. Some times these breathers were built into the oil filler cap.

Some old cars use to just take the outlet via a rubber hose to a metal pipe running straight down the side of the engine block and let it drip straight onto the road under the car.

This pipe was always on the opposite side of the exhaust manifold.

Not exactly the right thing to do today, id feel sorry for anyone hitting the brakes after id been sitting at the lights dripping oil. LOL

However the safest politically correct method would be using a catch can with a breather on it.

Run the breather pipe into it, it will collect any oil that may end over your engine and vent the outlet to atmosphere (via a breather filter if your fussy)

Ive seen them at super cheap auto, its exactly like my catch can but with a breather fitted. They could be advertised as power steering fluid containers or under a different label in the performance section.

The good thing is you can see if its caught any oil and you could add a small tap to drain it.

Exactly like this, but instead of a pipe in and out, its a pipe in and a filter out or a pipe in and the cap as a breather/filter.

Oh and its good to open it up via the 4 screws on top and add course stainless steel wool from the supermarket (kitchen scourers) it assists to keep the oil out of the outlet by trapping it into the s/steel wool.



You could use a unit like mine with a little breather filter on the outlet.

Food for thought.

[ozchips]

thanks for the idea mate
the one I have here does have baffles in it
it is a refillable one apparently
oil over the exhaust manifold lol , I would have gotten that already , you should see the oil cap mate , it has no thread and pretty much just sits there and is held on via to little 'L' shaped bits on the cap which slot into two bits sticking out of the cover lol
so it just sits there loosely and rattles about . I wanted to do something about this , but it seems it is normal lmao

[ozchips]

just one more thing , my old austin also has one of those breather pipes , it goes vertically and faces down straight onto the road

[kombiman]

ok my old 54 austin has an su on it and a dirty big airfilter with about 3 turns between the actual filter and the neck of the su , it used to have a carby and an older style oil filled filter
what I wondering is would i get any benefit out of fitting a ramflow air filter directly to the su (like the ones on the minis)
and instead of running a breather hose to the filter , just put a seperate breather on top of the motor .
My thinking is , in my climate this will be a lot better as it is more air and cooler air , also getting rid of the breather hose will stop hot oily air going in ?
Will there be any benefit , or will there be problems ?

Hey Oz,

Long time lurker, first post!

This is my kinda question

First measure the amont of pressure loss in the intake by using a magnehelic gauge or a manometer. This will tell you how restrictive your current set up is. It gives a baseline fo any mods. The ram flow ones usually are pretty crap and are only used on minis due to space, the larger air cleaner with the insert worked much better (on minis) but didnt sound as fast as the ram flo.

I had two different minis that I tweaked lots back in the day. I tried to convince myself that the ram flo worked but the better tuning with the paper element and the intake path it provided me converted me.

Often the guts of the air filter is actually a plenum to help the carb work better and to reduce fuel stand off.

I would use a better air filter than the ram flo with a spacer between it and the carb if possible.

Luck!

[ozchips]

trouble is like the mini , there is no room , the angle of the SU gives ony a few inches space . the current setup is a very thin flat pipe , rounding out to an air filter . This all up is nearly a foot long

[Godzilla]

No room go for a foam pod like mine.

Check if there is a trumpet inside or at least a curved radius to the su to help channel the air, i can assure you with the right element inside (not a zero $ one but a double or triple layer element) that air restriction is minimal, and i mean minimal.

Used on 1000+hp setups world wide.

Just dont look at the prices...(85,000 yen for a GTR)



Just make sure after cleaning that the triple layer element sits snugly with no gaps. Be careful some cleaner elements are not washable, check when buying.

You could drop a v8 in her using this filter and still have too much airflow.

[ozchips]

sounds good for an 800cc motor