WHY do some na FC's use more oil when going full exhaust+header? ya, I searched.
01-24-12, 05:45 PM
#1
Sideways is the only way
Thread Starter
iTrader: (2)
Join Date: Nov 2007
Location: Vermont
Posts: 958
Likes: 0
Received 0 Likes
on
0 Posts
WHY do some na FC's use more oil when going full exhaust+header? ya, I searched.
I asked a while ago why my rx7 went from being normal to using about a qt of oil every 600-700 miles of daily driving after I put on my racing beat header>rb presilencer> 2.5" crush bent mid pipe> shitty $25 thrush muffler and not having the O2 sensor hooked up. alls I got was people telling me my engines going or other people that had the same thing happen after they put an exhaust on (maybe not quite so much oil consumption as me but a big change).
I have an 86 na base or sport (had the duckbill wing, no wiper hatch, no sunroof, 4 pot front brakes,5 lug) stock other then the exhaust and PSM coilovers. Car had normal oil consumption for a 150k mile car with the hole riddled rusty stock exhaust. no split air pipe either if that matters. switched to the set up above and boom, burning oil like gas almost.
I want to know why this happens to some of us. I don't get it. I doubt everyones oil control rings or other internals are breaking when we do exhausts. it bugs me and I just want any explanation. someones gotta know whats going on with this.
I have an 86 na base or sport (had the duckbill wing, no wiper hatch, no sunroof, 4 pot front brakes,5 lug) stock other then the exhaust and PSM coilovers. Car had normal oil consumption for a 150k mile car with the hole riddled rusty stock exhaust. no split air pipe either if that matters. switched to the set up above and boom, burning oil like gas almost.
I want to know why this happens to some of us. I don't get it. I doubt everyones oil control rings or other internals are breaking when we do exhausts. it bugs me and I just want any explanation. someones gotta know whats going on with this.
01-24-12, 05:55 PM
#2
Moderator
iTrader: (3)
Join Date: Mar 2001
Location: https://www2.mazda.com/en/100th/
Posts: 30,986
Received 2,688 Likes
on
1,903 Posts
since the metering pump is rpm and throttle dependent, could it be that you're just driving harder?
01-24-12, 06:07 PM
#3
Besides the above-
Did you switch to a high detergent oil (something like Royal Purple) that will dissolve the carbon in the oil control rings and cause more oil consumption?
Did you move any vacuum lines?
Does it smoke at cold start or at high rpm?
About how much oil do you have to add?
Did you switch to a high detergent oil (something like Royal Purple) that will dissolve the carbon in the oil control rings and cause more oil consumption?
Did you move any vacuum lines?
Does it smoke at cold start or at high rpm?
About how much oil do you have to add?
01-24-12, 06:27 PM
#4
Sideways is the only way
Thread Starter
iTrader: (2)
Join Date: Nov 2007
Location: Vermont
Posts: 958
Likes: 0
Received 0 Likes
on
0 Posts
no, not driving hard at all because 1 more ticket means I lose my license. speed limit with averege acceleration always. I wind up the car in 1st to redline a couple times a week to keep it fresh but I have always done this for 3 years of owning the car.
20w50 castrol conventional always. I noticed my oil consumption so I changed my oil with more of the same but same thing. nothing else changed and double checked vac lines, plugs, etc. seems good. white smoke puff when started but it smells sweet and its white so its coolant seals. only lasts 5 seconds and goes away, been like that since I got the car too.
my oil light comes on around every 700 miles of daily driving. I add a little here and there to keep it topped off now. so its about a quart every 600-700 miles of daily driving.
idea: do you think that since my car is stock with a 2.5" exhaust that it requires more throttle/torque to get going? therefore using a little more oil all the time now? I'm in rural vt so not too much stop and go traffic.
20w50 castrol conventional always. I noticed my oil consumption so I changed my oil with more of the same but same thing. nothing else changed and double checked vac lines, plugs, etc. seems good. white smoke puff when started but it smells sweet and its white so its coolant seals. only lasts 5 seconds and goes away, been like that since I got the car too.
my oil light comes on around every 700 miles of daily driving. I add a little here and there to keep it topped off now. so its about a quart every 600-700 miles of daily driving.
idea: do you think that since my car is stock with a 2.5" exhaust that it requires more throttle/torque to get going? therefore using a little more oil all the time now? I'm in rural vt so not too much stop and go traffic.
01-26-12, 03:39 PM
#7
mainly because it's a 20 year old engine that is now breathing better. the oil seals are probably marginal at best and the engine is now able to push more oil out with the less constrictive exhaust.
i don't know why you're so worried about it, unless it is smoking like a train just drive it and keep the oil topped off. better to be using too much oil than less.
i don't know why you're so worried about it, unless it is smoking like a train just drive it and keep the oil topped off. better to be using too much oil than less.
Trending Topics
01-26-12, 06:07 PM
#8
Sideways is the only way
Thread Starter
iTrader: (2)
Join Date: Nov 2007
Location: Vermont
Posts: 958
Likes: 0
Received 0 Likes
on
0 Posts
well, all that oil adds up is why 
. if I could save a buck here and there why not? but ya, it runs the same. Would premix really help at all to save me a few bucks? I was told if my control rings were going it wouldn't make a difference.
karack, that makes sense I suppose. I was told that the oil metering system was throttle/rpm dependent so didn't see why it would use more? but I see where you're coming from now. I was just doubtful that just because the exhaust is less restrictive, it somehow caused my oil control rings to **** out on me.
car is currently stored for winter since november but getting ready for spring, figuring things out.
happy to know my clunk on hard shifts is the famous diff problem, without a broken mount in my case. $10 snubber mod should save my mount and stop clunking. I lowered my car late fall and use an adjustable camber link (your link karack) which apparently brings the diff closer to the chassis. since my mount wasn't broke I thought it was my trans or drivshaft since my trans mounts are toast. so back to body work now that the more serious problems are addressed. thank you guys.
. if I could save a buck here and there why not? but ya, it runs the same. Would premix really help at all to save me a few bucks? I was told if my control rings were going it wouldn't make a difference.karack, that makes sense I suppose. I was told that the oil metering system was throttle/rpm dependent so didn't see why it would use more? but I see where you're coming from now. I was just doubtful that just because the exhaust is less restrictive, it somehow caused my oil control rings to **** out on me.
car is currently stored for winter since november but getting ready for spring, figuring things out.
happy to know my clunk on hard shifts is the famous diff problem, without a broken mount in my case. $10 snubber mod should save my mount and stop clunking. I lowered my car late fall and use an adjustable camber link (your link karack) which apparently brings the diff closer to the chassis. since my mount wasn't broke I thought it was my trans or drivshaft since my trans mounts are toast. so back to body work now that the more serious problems are addressed. thank you guys.
01-27-12, 12:58 PM
#12
Moderator
iTrader: (3)
Join Date: Mar 2001
Location: https://www2.mazda.com/en/100th/
Posts: 30,986
Received 2,688 Likes
on
1,903 Posts
the better solution is to back off on the camber adjuster some.
01-27-12, 06:53 PM
#13
Sideways is the only way
Thread Starter
iTrader: (2)
Join Date: Nov 2007
Location: Vermont
Posts: 958
Likes: 0
Received 0 Likes
on
0 Posts
^the adj link is the only thing I have to take camber out right now and didn't realize it was hard on the drive shaft. I'm going to raise the car as I still have some negative camber (not slammed either) and my tires are bald so I need even wear till I get some more. If you guys haven't figured it out yet, I'm currently broke looking for a job so there isn't a huge budget here.
tuscanidream- no I'm not paranoid. well, maybe a little since I don't want my engine to die I haven't changed my driving habits before or after (except to test my new coils for a minute). I used to use about a 1qt every 1500-1600 miles (I consider that great for 150k miles daily driven/1 drift event) and now that has halved to 1qt every 600-700 miles. I've done the math. there is no oil drip or leak from the pan I can see, first place I checked really well multiple times. it might be leaking out somewhere that it can burn off but I never see any smoke or anything anywhere. I'll just deal with it till it gets worse or dies. I have another t2 motor torn down but no rebuild kit for like 2 years due to $$$ but I'll get a loan if I need to have another engine ready. My FC is my only car now since my impreza blew. I'll check to see if there is a way to check/test an s4 OMP and check that if I can.
tuscanidream- no I'm not paranoid. well, maybe a little since I don't want my engine to die
I haven't changed my driving habits before or after (except to test my new coils for a minute). I used to use about a 1qt every 1500-1600 miles (I consider that great for 150k miles daily driven/1 drift event) and now that has halved to 1qt every 600-700 miles. I've done the math. there is no oil drip or leak from the pan I can see, first place I checked really well multiple times. it might be leaking out somewhere that it can burn off but I never see any smoke or anything anywhere. I'll just deal with it till it gets worse or dies. I have another t2 motor torn down but no rebuild kit for like 2 years due to $$$ but I'll get a loan if I need to have another engine ready. My FC is my only car now since my impreza blew. I'll check to see if there is a way to check/test an s4 OMP and check that if I can.
Thread
Thread Starter
Forum
Replies
Last Post