Honda Prelude Forum banner
1 - 20 of 26 Posts

·
Registered
Joined
·
22 Posts
Discussion Starter · #1 ·
Quick question, so i have a lot of spare 3 in intercooler piping from a turbo build on my friends GS300. He was joking around saying i should make an intake with it. My question is, Can i just clamp on some piping and a filter? or are there necessary vacuum lines and sensors that go into the intake. I know his GS has a MAF sensor and i dont think 90 prelude have them so i don't have to worry about that. If it is possible, is 3in intake too much airflow.

thanks
 

·
Premium Member
Joined
·
16,911 Posts
Quick question, so i have a lot of spare 3 in intercooler piping from a turbo build on my friends GS300. He was joking around saying i should make an intake with it. My question is, Can i just clamp on some piping and a filter? or are there necessary vacuum lines and sensors that go into the intake. I know his GS has a MAF sensor and i dont think 90 prelude have them so i don't have to worry about that. If it is possible, is 3in intake too much airflow.

thanks
No need, we do not have any sensors on the intake.
 

·
Registered
Joined
·
276 Posts
Thats why they make a air cleaner for the hose off your valve cover it and you don't need any other parts other then maybe a K&N air filter and some boots and clamps !
 

·
Registered
Joined
·
10,750 Posts
Thats why they make a air cleaner for the hose off your valve cover it
Actually they don't, they use that filter when people use intakes that don't have the fitting to put it in.
Not using it removes part of the PCV system and isn't necessarily a good idea.
 

·
Registered
Joined
·
455 Posts
Thats why they make a air cleaner for the hose off your valve cover it and you don't need any other parts other then maybe a K&N air filter and some boots and clamps !
If you seep oil, taking the vacuum line off will let it leak. Any 'case pumping' is very hard on seals especially old ones. Trust me, when the pistons are going up and down the bores, there is a bunch of air being pushed around in your crankcase.
 

·
Premium Member
Joined
·
16,906 Posts

·
Registered
Joined
·
10,750 Posts
Not entirely.
A catch can should go in the PCV to intake plenum hose.
The hose on the intake tube is straight through (sometimes with a reducer) from the cam cover and relies on intake pressure/vacuum in the intake pipe (hence the slash end on the fitting) to remove the gases and put them into the intake stream.

Not entirely sure which type of can you had in mind so maybe you're thinking of something different to me.
 

·
Registered
Joined
·
10,750 Posts
Yeah but that's absolutely nothing like the stock system that we are talking about or one that 99.9% of folk here would use.
 

·
Premium Member
Joined
·
16,906 Posts

·
Registered
Joined
·
567 Posts
Honestly dude, to answer your question you CAN just use it as an intake. We have no sensors before the throttle body and only the vaccum source for the PCV system. If you just buy an $8 breather filter and put that on the valve cover you'll be alright. Also it will keep your intake from getting all crudded up with oil like the factory setup theirby improving your combustion which translates into better HP and MPG.
 

·
Registered
Joined
·
471 Posts
Honestly dude, to answer your question you CAN just use it as an intake. We have no sensors before the throttle body and only the vaccum source for the PCV system. If you just buy an $8 breather filter and put that on the valve cover you'll be alright. Also it will keep your intake from getting all crudded up with oil like the factory setup theirby improving your combustion which translates into better HP and MPG.
you are right about that i did that to mine and it works great you dont notice a different in hp though but it is better
 

·
Registered
Joined
·
10,750 Posts
Honestly dude, to answer your question you CAN just use it as an intake. We have no sensors before the throttle body and only the vaccum source for the PCV system. If you just buy an $8 breather filter and put that on the valve cover you'll be alright.
Yes it will be 'alright'.

Also it will keep your intake from getting all crudded up with oil like the factory setup theirby improving your combustion which translates into better HP and MPG.
It may stop the intake getting dirty but that is the stuff you're then leaving in the engine/oil, which is what the PCV system is there to remove.

I'd rather recycle it into the intake and burn it off and lose that 1bhp than keep it in my oil where it does more harm.

How much crud is down to how clean the engine runs.
 

·
Registered
Joined
·
567 Posts
If you do regular oil changes you won't have an issue. I've used breather filters for years and never had a problem. And as for running cleaner, techically it's better with the breather on because the only things getting in the intake is air. That means the only thing in the combustion chamber is air and gas. A more complete burn means better emisions. So to me it seems cleaner inside and out with the breather. Now ideally I would want a oil catch can routed to a vaccum source but he's obviously looking for a 'budget' fix.
 

·
Registered
Joined
·
22 Posts
Discussion Starter · #17 ·
If you do regular oil changes you won't have an issue. I've used breather filters for years and never had a problem. And as for running cleaner, techically it's better with the breather on because the only things getting in the intake is air. That means the only thing in the combustion chamber is air and gas. A more complete burn means better emisions. So to me it seems cleaner inside and out with the breather. Now ideally I would want a oil catch can routed to a vaccum source but he's obviously looking for a 'budget' fix.
yeah im lookin to change the oil like every 2000-2500 miles because its a B21A1 with 140000miles and it burns oil so before it starts burning oil im just going to change it anyways. what is this oil catch can where would i put it.
 

·
Registered
Joined
·
567 Posts
yeah im lookin to change the oil like every 2000-2500 miles because its a B21A1 with 140000miles and it burns oil so before it starts burning oil im just going to change it anyways. what is this oil catch can where would i put it.
It goes in between the intake and where it connects to the valve cover.




With this it gives you the vaccum needed to have the PCV system continue to work. However, with the old system it was just a tube and with the vaccum it just sucked up whatever was on the other side i.e. oil. With this the vaccum is there but it pressurizes the catch can which then sucks on the valve cover and sucks out the fumes and oil splashes. but intead of sucking it into the intake, the oil drops into the bottom of the catch can. Now you may think it would just continue to suck up the oil, but with another opening (the hose to the VC) the vaccum follows the path of least resistance and keeps sucking from the VC hose.
 

·
Banned
Joined
·
13,157 Posts
you guys are on crack, you're all mixed up about that VC breather tube lmao.

to the op: yes you can just make an intake with that piping and a filter, just be sure to put a crankcase breather filter on the VC port after removing the hose.

to all you other guys: the VC breather is mainly an inlet going INTO the crankcase. the only time its an outlet is when you have excessive blowby. the pcv valve is the actual outlet going into the intake manifold. the only reason the engine has the breather port is so that when the car is at high vacuum and sucking air in through the pcv valve, the air has to be replenished somehow to keep the crankcase at ambient pressure instead of in vacuum, so the breather is the inlet to let the air into the crankcase. the only purpose of the hose leading to the intake pipe is so that the air going into the crankcase is filtered air. it is not under vacuum or pressure at any point in time whatsoever, it is at ambient pressure at all times. vacuum is only seen between the TB and the head, not in the intake pipe.
so yes, breather filters really are just that; breather filters. so that when you remove the hose between the VC and the stock intake pipe, the air going INTO the crankcase is still filtered air and not dirty dusty air that will contaminate the oil.
 

·
Registered
Joined
·
10,750 Posts
I must be on crack then.
Or are we sharing yours? :lol:
but then we can't all know absolutely everything all the time can we.
http://www.autoshop101.com/forms/h63.pdf

That breather is both an inlet and outlet depending on conditions.

but my original posts are 100% correct anyway.

We have covere this one a few times:

Oooooo... look at the last post in this one:
http://www.preludepower.com/forums/showthread.php?t=225027&highlight=PCV+system

Then there's this elaborate debate >
http://www.preludepower.com/forums/showthread.php?p=302882&highlight=PCV+system#post302882

There are one or two others but they're mainyl me and Dano reminiscing about the olden days :)
 
1 - 20 of 26 Posts
Top