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Discussion Starter · #1 ·
Ok, so heres an idea that i've been thinking over for a very long time now

since i am now just newly turbo'd on my klze, i was wondering if for long trips i was able to do this;

disconnect, and or turn one of my intercooler piping downwards towards the ground, or somewhere to dump out so it wouldn't continue flowing through the rest of the intercooler piping back into the engine.

the purpose would be for longer trips, to not be in boost, engine wise, at all, thus having the same gas efficiency as stock?

are there any problems with this idea? Everything will still be hooked up the same, just one single pipe or coupler will be removed or spun to make the air dump out instead of in

Would the turbo spool up to unlimited boost if the external wastegate is not attached to the turbo? or should i have the external wastegate set to dump all the time? I
s there anyway to set an external wastegate to dump all the time so it wont build boost? which intern is what im trying to say above, but with couplers and or intercooler piping

any constructive criticism would be nice
 

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Is a slap constructive critizisim?? :).

it will negatively effect your fuel economy. I do believe having the turbo blowing into nothing (which it will be doing) is bad for the turbo. Just when you drive dont get into boost. It will be like driving non turbo, just dont boost it :p.

Im not sure what it would do the wastegate. If it is connected to the intercooler piping near the Throttle body where it should be, it will always see 0 vac so yes I suppose it would keep boosting. But then again you will just have one big fuck off air leak so it might not even build boost. That is probably why they say it will fuck the turbo. Spinning hard enough to build 30psi, but not building shit because it is venting to atmo.

Cliff notes, dont do it. Just drive normally and dont hit boost and you will notice 0 difference. In fact, turbo will get you Better fuel economy assuming it is tuned right or on stock ECU.
 

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ok for one dont listen to that you will ruin your turbo if not piped up bullshit... you can run your turbo not piped up everyday of the week if you want... BUT number one thing is watching out to make sure nothing flys up into the turbo for any reason... but other then that you have nothing to worry about...

but im with turk on this one... just drive slow and steady with no boost and you will be fine...
 

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Discussion Starter · #6 ·
Well i thought the idea of a wastegate is to dump out excess air for the desired psi, set by the spring inside the wastegate, or boost controller? So that excess boost can't be built up beyond that spring weight

so with the wastegate being open, wouldn't i be only building up to 5 psi? or whatever the spring is set to?

i plan on doing hwy trips, and i've noticed that im cruising at around 4000 rpm's, so being in boost, for that long amount of time will most likely do something bad to my engine. as i think

and i do drive normally, i get 700km's or 434 miles to a full tank, and i suspect that is pretty good lol
 

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If you disconnect one of your intercooler pipes and step on the gas even probablly half throttle your going to spin that turbo like no tommorow man. Probablly mess up the bearing, and especially if there is any shaft play your going to damage the turbo bad. Your running in vacuum anyways, so I do not see any benefit to bypassing your pipes.


If your cruising around at 4K RPMS you should not be in boost unless you have a undersized turbo. It will boost initially, but after you are at cruising speed it should back off to nearly full vacuum.



My personal opinion is your turbo may be undersized and I wouldnt change anything from the way it is setup now (properly)
 

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Discussion Starter · #8 ·
im using a t3/t04 60 trim, and are you sure the boost backs off if kept at the same rpm and same speed?

so to say, i am at 5 psi at 4500 rpms or something, and i maintain that 4500 rpms, would i not be at 5psi until i let off, and since the wastegate is prohibiting it from more than 5 psi? or does boost actually drop if kept at say the 4500 rpms? Cause i would still be thinking that the motor will be pushing the same amount of air the initial acceleration compared to constant held rpm a few minutes down the road? or am i wrong on that
 

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Ok lets say you accelerate to 5K rpms. You will be in boost until you hold those RPM's for maybe 1-2 seconds, after the load is removed from the engine and you begin to cruise you will have very light foot on the gas and you will be back into vacuum. (as soon as you back off the throttle to go into RPM holding)

If you dont have a boost gauge that is exactlly what is happening, if you have one you should see what I am talking about.

If it it holding boost at cruising speed there is something wrong.

It will not be moving the same amount of air because when your in vacuum there is less air in the cylinder than when you are in boost.
 

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stealth is right...

its kinda like a torque converter in an automatic transmission. initially as you hit the gas the the flywheel spins faster than the turbine but as you reach cruising speeds their speeds almost match...the difference in speeds between the two parts of the torque converter is needed for acceleration...just like you need a large amount of exhaust flow (at WOT) to cause the turbo to spin faster

initially as you hit WOT the turbo rpms are rising getting you into boost...at cruising speeds you're maybe at 10% throttle which will not put you into boost no matter the rpm's....unless you have a really small turbo as stealth said...
 

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Discussion Starter · #11 ·
well that just explains it, i was always second thinking that i would be in CONSTANT boost at that certain rpms, so when cruising on the hwy i'd be at full boost at say 4500rpms for a very long time, and i dont think that would be very good at all

so pretty much, i think i am good then now and i can go ahead and hook up everything
 

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Discussion Starter · #13 · (Edited)
lol i have my turbo installed, besides this one coupler, which im waiting on to get till tomorrow

but i've run into one problem, and that is my throttle gets stuck or seems like it does..

i start my car, it idles fine, and then when i rev it, to like 2k it will stay there, until i pull the pedal back manually, if i keep taping the gas it will keep rising and staying at that point, but the throttle comes back to the first initial tap of the gas... i also turned off my car, and then started it up again, but the funny thing is, its back to the normal rpms, which is 600 for me.. so if the throttle was stuck at whatever certain point it was at, wouldn't it shoot up to what it was before i shut it off or the first initial tap?

i dont know if this relates or not, but i have my cruise control unbolted at the moment, and is kinda chillen in a spot that may or may not be added stress to that cable line thing, im not so familier with the cruise control system, but could it be that the cruise control cable is pulling on the cable too?

and another question, relates to my fmu, there are 2 ends, one comes out directly out of the center, and then theres one that comes out off center or to the side but on the bottom, which one line goes to the fpr? and im going to assume the other one goes to the other tube back to the tank

also, my wideband, shows 22.3 at idle.. im going to assume that is not right at all lol.. is there any particular reason to why it is reading that? and thats with my turbo not hooked up as in no forced air from the turbo.. i also have a pretty big exhaust leak at the downpipe
 

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Drive the a turbo car then you will understand. Otherwise Im suprised King didnt link the How turbochargers/wastegates work at howthignswork.com yet:). You need to get your head around how the wastegate works, it does not let out air, it lets out exhaust gases that would otherwise build more boost.

Also when it comes to drive a turbo car, you will realise that you can be at 7000rpm and have 0psi boost. It is about engine load not RPM that builds boost, when people measure and say "I have full boost by 4000rpm" we are always assuming full throttle. I can drive all day in traffic with the ZE-T and not hit boost once.

RScircuitcity you shouldnt spread misinformation.
 

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Its probablly your cruise control holding your throttle down, I would fix that right away or just take it out all together. Pull the rubber boot back on the CC module and you can disconnect the cable from it.

Your O2 sounds like its out of whack because you dont have the FMU hooked up properly. IW ould figure out the FMU and get that working also. (i have never used a FMU so I dont know what ports are what)
 

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i ran with my turbo setup on just a CAI for over 2 weeks. i floored the shit out of it too, and it wasnt untill i hooked it back up that i realized that the turbo was just spinning as fast as that little fucker could cause nothing would slow it down :)


but, after that, it hasnt blown any more oil :D
 

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Discussion Starter · #17 ·
I havn't had a real chance to drive the car around , besides to the exhaust shop and back, and it sounds badass with open exhaust haha

i figured out my problem with my stuck throttle, as i hooked up a vaccum line wrong on the cruise control, therefore forcing it to stay in cruise or lock mode or whatever it may be, and keep it at whatever speed or rpm i kept it at.. thats my speculation lol

but i removed it, and all works out

i also removed my fmu and just ran the regular line, but my wideband is reading like intense lean.. but it also could be that i have an exhaust leak cause i forgot to put in a t3 exhaust gasket, since when i give it more gas to flow more, the wideband goes to 13 or so , so im going to assume my exhaust leak is just leaking out the precious wideband reading .. i think ?
 

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are you running lean in boost because if you are running lean then it makes sense because your not putting enough fuel into the engine which is what the fmu is for.
 

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Discussion Starter · #19 ·
im not running any boost at all, i dont have all the intercooler piping connected

im running lean 22.4 at idle 600 rpms..

i was reading up the lc-1 manual, and i read up that if there is any type of exhaust leak, the reading will be off quite a bit, so im going to hope thats it, or unless i didnt calibrate the wideband? who knows
 

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Bad calibiratation shouldnt be that off. Either exhaust leak or maybe not a good ground for the Lc-1. I know my ground was shit and was giving me all kinds of strife.
 
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