catch can on intake?
#103
Registered User
Join Date: Aug 2004
Location: Des Moines, Iowa
Posts: 495
Likes: 0
Received 0 Likes
on
0 Posts
So are our Crankcases constantly running then at approximately -15 inches of Hg? If no "air" is getting into the crankcase to replace what has been pulled out then we should be running a vacuum in the crankcase....?
#106
road draft tube is a "no brainer". just run a tube from the oil filler neck to beneath the car(choose your own location) shield the tip of the tube with material of choice. Make the shield a little funnel shaped and there you have it. Dont have bends in the tube.
olddragger
olddragger
#107
here's what i had in mind...
attach a 90degree fitting to the oil stem & run a 3/8" vacuum hose down beneath the car from it...
my question is...
how can i achieve some kind of vacuum?
attach a 90degree fitting to the oil stem & run a 3/8" vacuum hose down beneath the car from it...
my question is...
how can i achieve some kind of vacuum?
#110
i've seen some that have a 90-deg bend at the very bottom and have a small hole drilled at the FRONT side of the tube that faces the FRONT of the vehicle... this would get the air through the hole flowing straight out of the REAR eixt... i guess this is what would cause the most amount of gases to exit out of the pipe as the car moves...
is this logic right???
is this logic right???
#112
Originally Posted by olddragger
learning a lot here! My bad. I always thought that the airflow pass the fitting would provide a "suction" kind of like the front of the intake. Prehaps I am wrong. Stealth are you saying we have Ram Air affect going on?
I do know this. I tried the guys suggestion--now letting the catch can act as a breather/filter(yes there is an odor present but not bad at all) and I capped the intake fitting--------------------------- and
-------there is increased throttle response-----noticeable. Dudes---thanks! I am unsure if WOT is any better but partial and anything below 3/4 throttle is much better. I already had a smooth idle so I cant verify that. If there are no negative affects from this --- then this is a good mod!
Now the question is "Why"
olddragger
I do know this. I tried the guys suggestion--now letting the catch can act as a breather/filter(yes there is an odor present but not bad at all) and I capped the intake fitting--------------------------- and
![Smilie](https://www.rx8club.com/images/smilies/smile.gif)
Now the question is "Why"
olddragger
Because the engine wants pure oxygen and the fuel mixed in from the MAF.
Doesn't like poluted air. Hard to burn or uneven burn in chamber?
#114
Registered User
Join Date: Aug 2004
Location: Des Moines, Iowa
Posts: 495
Likes: 0
Received 0 Likes
on
0 Posts
So are our Crankcases constantly running then at approximately -15 inches of Hg (Vacuum)? If no "air" is getting into the crankcase to replace what has been pulled out, then all of our crankcases are running in a vacuum???
#116
Registered
iTrader: (1)
Originally Posted by Jaguar_MBA
So are our Crankcases constantly running then at approximately -15 inches of Hg (Vacuum)? If no "air" is getting into the crankcase to replace what has been pulled out, then all of our crankcases are running in a vacuum???
#117
If you turbo your car do you just leave this line unhooked also? Or do they want you to run it down to infront of the turbo?
Ive seen some pictures of the RX8 with the Catch can installed but no return line,just a breather.
Ive seen some pictures of the RX8 with the Catch can installed but no return line,just a breather.
#118
opinion
Originally Posted by r0tor
Oil resevoirs for all kinds of machinery are usually kept under a slight vacuum. It keeps water out of the oil, burned oil vapors out of the oil, reduces leaks in some cases, and improves oil return flow.
#121
I would say it is more responsive.
And anything to make the intake air cooler is good for me.
So far no oil mess from the filter. I believe those are old war stories and instances from old cars that make a mess.
In fact my 65 Ford does make a mess when I disconnect the tube and let it hang.
She has alot of unburned mixture to return to the intake.
New technology has reduce this signifigantly.
And anything to make the intake air cooler is good for me.
So far no oil mess from the filter. I believe those are old war stories and instances from old cars that make a mess.
In fact my 65 Ford does make a mess when I disconnect the tube and let it hang.
She has alot of unburned mixture to return to the intake.
New technology has reduce this signifigantly.
#123
Originally Posted by Razz1
I would say it is more responsive.
And anything to make the intake air cooler is good for me.
So far no oil mess from the filter. I believe those are old war stories and instances from old cars that make a mess.
In fact my 65 Ford does make a mess when I disconnect the tube and let it hang.
She has alot of unburned mixture to return to the intake.
New technology has reduce this signifigantly.
And anything to make the intake air cooler is good for me.
So far no oil mess from the filter. I believe those are old war stories and instances from old cars that make a mess.
In fact my 65 Ford does make a mess when I disconnect the tube and let it hang.
She has alot of unburned mixture to return to the intake.
New technology has reduce this signifigantly.
![Ylsuper](https://www.rx8club.com/images/smilies/ylsuper.gif)
#125
guys --you will not feel a positive pressure from the oil filler tube when the engine is running in the driveway--at least I couldnt. Neither could I feel a vacumn from the intake connector being used by the hose from the oil filler neck. matter of fact there was no change in the way my car ran(for a short distance) with that intake connector open. That surprised me. Thought I would have at least a little rough idle.
Now I have had blowback and that is guaranteed positive pressure in our "crankcase". I had a large amount at one time. Small amount on several occasions. Since this mod I have had none. But it has only been on for a little while. No condensation in my oil either since this mod--did have a little before it.
I did do the downdraft tube thing but from my oil catch can- not directly from the oil filler neck. I dont like messes.
No one has answered my question concerning the tube that goes to the oil metering pump and what is its purpose. No one has any idea?
FI --I believe will need some modification to the crankcase vent system--dont know how much but in some recip's they have to add a 2nd and sometimes a 3nd pcv valve to get good seal. Heck some "strong" FI engines actually install a vacumn pump.
I am now finally able to voice what my engines response is to this mod. In cold weather and the engine is warming up the engine response to partial throttle is stronger. it pulls stronger than it does after the engine has warmed. That is how it feels now all the time. Cant really tell a differance in WOT. By the way does our car disconnect the egr at WOT?
olddragger
Now I have had blowback and that is guaranteed positive pressure in our "crankcase". I had a large amount at one time. Small amount on several occasions. Since this mod I have had none. But it has only been on for a little while. No condensation in my oil either since this mod--did have a little before it.
I did do the downdraft tube thing but from my oil catch can- not directly from the oil filler neck. I dont like messes.
No one has answered my question concerning the tube that goes to the oil metering pump and what is its purpose. No one has any idea?
FI --I believe will need some modification to the crankcase vent system--dont know how much but in some recip's they have to add a 2nd and sometimes a 3nd pcv valve to get good seal. Heck some "strong" FI engines actually install a vacumn pump.
I am now finally able to voice what my engines response is to this mod. In cold weather and the engine is warming up the engine response to partial throttle is stronger. it pulls stronger than it does after the engine has warmed. That is how it feels now all the time. Cant really tell a differance in WOT. By the way does our car disconnect the egr at WOT?
olddragger