how to eliminate blowby for ka-t?

[kouki_hmongster]

my set-up: fresh fully built 91 ka24de-t25(bigger turbo after break-in)

okay i am kind of confused about using a catch can to collect blow by gas. i'm planning to boost around max of 16psi later in the future and i'm installing the engine soon. from what i remember off threads from nico is that i can connect the hose from the pcv valve to a catch can and then connect the catch can to intake pipe before turbo. also connect valve cover breather to intake pipe before turbo.

then i would also have to block off the hose that originally goes from breather separator(black box by waterpump) to pcv valve and into intake manifold to engine. i meant block off the hole that goes into intakemanifold so that there wouldnt be any vac leak.

is this all right? i'm not too sure, also is it necessary to do this whole set-up? anyone run the stock set-up and havent have any problem boosting high?

thanks in advance
Modified by kouki_hmongster at 11:23 PM 8/25/2008

[kouki_hmongster]

come on i know someone knows this stuff. i dont want to drop in my motor and find out that i have to do this set-up for blow by.

[neverlift]

um uh search noone has responded due to the fact a couple "blow by" threads are on here in VERY descriptive detail

I just run a line from vc to turbo inlet pipe, messy but who cares its fast

[kouki_hmongster]

yeah i searched but most of them are for sr. and the ka-t's are kind of vague. well if anyone know a good thread then post it up, but of course i am still searching.

i heard going from valve cover breather to turbo inlet pipe wasnt how your suppose to catch blow by gas. so thats why i've been searching around even looked at the fsm thats why i got concern about this whole blow by thing.

thanks

[neverlift]

well I was speaking more in refference to removing air from the v/c

I let my pcv dump to atmosphere, I fail...

[nissanfanatic]

So do I.

The SR's stock setup isn't bad. I just hate the idea of running blowby into the intake...

[neverlift]

So do I.

The SR's stock setup isn't bad. I just hate the idea of running blowby into the intake...

but it works so good, my diy catch can seemed to hinder performance of the system vs straight into it the intake pipe.....

I'll be redoing it soon....

one of those it can wait deals.

[WDRacing]

Read this...

http://www.stealth316.com/2-krankvents.htm

[kouki_hmongster]

Read this...

http://www.stealth316.com/2-krankvents.htm

Wow thanks WD this is some really helpful stuff, so does it mean that i dont need to have an oil catch can that goes from valve cover breather to turbo inlet since going to be using this big kv? also wouldnt have to worry about blowby gas getting into crankcase.

for only $110 isnt bad at all if this really works. so now i want to know if anyone on the ka-t forum own one.

[WDRacing]

I doubt anyone owns one...there are several different options along those lines available. Google PCV Removal or PCV in general and all kinds of really good info is out there. I was contemplating a crankcase pump for awhile.

WD

[neverlift]

when I tried to run my pcv into my turbo inlet I got smoke... I think both was overkill, I get no smoke with just my vc line ran into the turbo inlet pipe....

what kinda power you think it would gain wd? IIRC the old skewl guys claimed way more than I feel the ka or any 4 banger would gain...

[WDRacing]

Well, it depends on the total output of the motor. A guy making over 500 achieved gains of 30hp. But it's also removing a metric ton of crap from the oil by sealing the rings. So you get better combustion and better lubrication.

But the price is $350ish for what I was looking at.

[nissanfanatic]

What I do now is run a hose from my coldpipe to the valvecover port. I have a fitting that is restricted quite a bit. I basically played it by ear, but it doesn't let much air at all through at all using an air compressor. Then I have my PCV open to air. I'm guessing that this allows for a flow of fresh air to circulate through the engine, or at least through the front timing cover. It is at least as good as stock IMO.

[neverlift]

with a filter on maybe, so that no debris can enter the system what so ever.

But I dont have a filter, nor intend to get one.

[nissanfanatic]

An air filter?

[2FourTee]

What I do now is run a hose from my coldpipe to the valvecover port. I have a fitting that is restricted quite a bit.

Can you give some more info on what you mean by "restricted quite a bit". Are we talking a pin sized hole or...?

[nissanfanatic]

Yea, pretty small. I basically crushed the barb fitting in a vice until it was restricted a lot. IDK the exact size of the orifice. I wanted it to be a very small boost leak that I could tune for. Fortunately, it didn't make much of a difference in AFR.

[NateDogg]

That is a good idea that Greaser had a few years ago. Keeps fresh air circulating through the crankcase. The benefit is to reduce windage and increase oil life.

I have a pipe fitting on the oil separator that has a line that goes to a catch can, then to the turbo inlet with a slash cut through a PCV in a rubber grommet. This hopefully helps draw some of the crankcase pressure via the bernoulli effect, thus increasing cylinder sealing and reducing windage.I got this kit from http://www.theoldone.com.

By dumping the oil separator line to the ground, you are not achieving any vacuum, however you are also not recirculating any blow-by into the intake. It's all a give and take that may warrant some trial and error.

I have chosen to recirculate. Also, my KA-T passed emissions better than without turbo.

On a low boost motor I would probably recirculate, however high boost applications may generate so much blow-by that recirculating the crankcase fumes could cause detonation/loss of power.

[nissanfanatic]

I think the best modification to this system would be to have air enter the rear of the valvecover and exit at the rear of the block. This would stream air through the entire engine.

[neverlift]

talking about a small filter on the end of the pcv line that is ota.

hey nissanfanatic did you mean rear of vc to front of block?

nate: yes but having the vc tied in to turbo inlet does

also, I will be hooking the pcv to turbo inlet again just minus the 'hood' catch can I had on it...