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Now...Whitesupra94
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hey guys,

i dont notice this all the time, and its usually in second gear when i do. mainly cuz ive never reached the top of third and first goes by too fast. anyhow...it sounds like its coming from the intake((apexi power intake )) it sounds like theres a piece of paper flapping really fast... is that just the air flowing thru the filter material...((or possibly a slight rip in the material?))? or is there something i should be watching out for. anyone had this problem...its like a slight rattle/gurgle.((the best way to describe it would be like a slightly loose bolt rattling type of sound)) it sounds like its coming from the engine bay...kinda from the air vent, but i cant be sure as to exact location.
i dont wanna take the car to the track if its not sounding good. ive noticed it before, sometimes its louder than other, sometiems its not there at all.
any ideas?
thanks
Bob
 

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Is your throttle/cruise control cable bracket assy. real close to the strut tower brace?

I have the TRD brace and I had to grind about 1/8' off the top of the bracket assy to eliminate a rattle noise.
 

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bump, i would like other peoples opinions on this, as im also experiencing this in second gear, could not explain it any better than the op, sounds like a piece of paper flapping real fast
 

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Japanese Tuning in Plain English

bump, i would like other peoples opinions on this, as im also experiencing this in second gear, could not explain it any better than the op, sounds like a piece of paper flapping real fast
I was gonna say his lower plastic panels were flapping... now another confirmed description...

hmmn... So... what you guys are hearing is coming from intake... not hard flapping, more paper like... perhaps like a "reed valve" would flap? I always say, no one knows their own car better... the better you can describe your symptoms to a doctor, the better he can assist.

There is a reed valve inside the Intake Air Control Valve.

A reed type valve is used so when the second turbo comes on or off, the boost blends in or out at a smoother rate...It's closed at lower speeds/RPM (actually load) when on the primary turbo and open when secondary turbo come on.

You can expect the "spring metal", as seen on the back of reed type valves, to be worn or cracked eventually at some point. I'm wise to assume the "reed" is worn or loosely flapping away when open... the spring metal will surely break if not already.

I don't know if Toyota sells those parts individually... probably just the whole IACV. Open it up and look inside...

Choritsu-shi
 

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I personally am running a single turbo, and an aftermarket intake, Its hard to exactly decipher where the sound is coming from, my car hasnt ran in about a month, finally got it back up and running, it drives fine normally, i decided to go on the highway and do a few pulls to make sure it was okay to run in that sense,

i first tried this in second gear, when i floor it my car and rpms are fine, until i get to 5krpm-redline the car starts to vibrate a little excessive(maybe not excessive but at least enough to know it might not be normal) with a noticeable flutter/paper flapping sound.
arts
So i decide to try this in various methods, im on the highway, i slow down, drop it into third at about 40mph, i brake boost to about 7lbs and floor it, again the car holds fine until 5-5.5krpm to redline then starts vibrating/making the flutter/paper flapping sound. But while vibrating it pulls very strong. shift into fourth and again vibrating and flutter sounds starts at the same time.

The next thing i did was start in fourth gear (40mph) brake boost to about the same. Then when i floor it at about 4kprm-5krpm that flutter sound comes first, and very loud, then 5krpm hits and the vibration starts.

I asked my tuner, and he said, when i explained the flutter sound, to him it sounded like spark blowout, It makes sense, but i did think that it was my spark i would notice differences somewhere else as well, although it does make sense that i make full boost at the rpms im seeing these things happen at.
 

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Japanese Tuning in Plain English

:eek:Dude....you're breaking up big time!(detonating):faint: Stop pushing it... you're doing way more damage than you realize.... and wtf is brake boost?


You need to either lower your maximum boost, use a higher octane fuel and/or use colder range sparkplugs. Reducing sparkplug gap may help, but it's not the correct fix as everybody here assumes. I always recommend and use HKS spark plugs because they are the only sparkplugs that are specifically designed for high power gasoline turbocharged applications.

So i decide to try this in various methods, im on the highway, i slow down, drop it into third at about 40mph, i brake boost to about 7lbs and floor it, again the car holds fine until 5-5.5krpm to redline then starts vibrating/making the flutter/paper flapping sound. But while vibrating it pulls very strong. shift into fourth and again vibrating and flutter sounds starts at the same time.

The next thing i did was start in fourth gear (40mph) brake boost to about the same. Then when i floor it at about 4kprm-5krpm that flutter sound comes first, and very loud, then 5krpm hits and the vibration starts.
According to your tests... At 40mph your fluttering sound (detonation) starts at 4000 rpm in 4th gear.... although at 5000rpm in 3rd gear. That's understandable because in 4th gear you will have more load than in 3rd gear.

Turbochargers are load dependent... as load increases, boost increases.
If you were going uphill, the detonating would probably start much earlier....because there's more load and therefore more boost when going uphill.
If you're going downhill you probably won't detonate because there is less load and therfore less or no boost. When cruising on the highway at 4000 rpm... there is less load, that's why you will have little to no boost.

Superchargers are RPM dependent... as RPM increases, boost increases.
If a Supercharger develops 10psi boost at 4000rpm... then whether accelerating or decelerating... going uphill or downhill, or cruising on the highway... at 4000rpm, boost will always be 10 psi.


I asked my tuner, and he said, when i explained the flutter sound, to him it sounded like spark blowout, It makes sense, but i did think that it was my spark i would notice differences somewhere else as well, although it does make sense that i make full boost at the rpms im seeing these things happen at.
Detonation occurs under high load conditions...which produces maximum boost and and not necessarily at a specific RPM. (as in your tests) This would also be where you are developing the most torque... torque is what breaks engines, not horsepower. (so will a bad tune.)
.
It is, what it is. A tuner is...what a tuner does. He's not a tuner and you're not in proper tune.

Choritsu-shi
 

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hmm, i guess thats the downside to having a supra in southwest kansas, my tuner lives six hours away, in my town, there is noone near professionial enough to touch a supra.

I do believe that maybe my gap is off, i took my intake manifold/sparks off like 20 times last week to try and figure out the culprit of a misfire/weird idle, which was my cam position sensor. fixed that, but possible messed up my spark gaps without realizing it. I have my gaps set at .020, also im running 91 pump gas pushin about 481rwhp/373 tq so it im not running an excessive amount of hp and torque.

Anything i can check on my aem that might help me figure out my problem?
 

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adammackintosh.net
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be careful if it is detonation/knock/pinging. one of these times a piston is going to launch out the side of your block rather than make some knocking sounds.

you could melt the sides of your pistons or valves. i believe signs can be noticed by looking at the spark plugs. could be a wise choice to take them all out and post some closeup pictures of them.
people on here will be able to spot detonation on the plugs, and/or the plugs will be melted and wacked out looking. or at the very least people on here can spot if your tune looks bad if its too rich or lean, etc. some wizards here.

the aem also should have some knock control graphs/screens i dont know where but i think it has some. my aem v2 has some knock based retard settings so i assume it has an area to view the knock its picking up.
 

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i think its safe to say im not detonating! by the way others have explained what it sounds like, doesnt sound like the sounds from my car, sounds more like spark blowout! but i will for sure take the spark plugs out today and check them. Thanks for all the input hough, really appreciate it, anything helps.
 

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Japanese Tuning in Plain English

hmm, i guess thats the downside to having a supra in southwest kansas, my tuner lives six hours away, in my town, there is noone near professionial enough to touch a supra.

I do believe that maybe my gap is off, i took my intake manifold/sparks off like 20 times last week to try and figure out the culprit of a misfire/weird idle, which was my cam position sensor. fixed that, but possible messed up my spark gaps without realizing it. I have my gaps set at .020, also im running 91 pump gas pushin about 481rwhp/373 tq so it im not running an excessive amount of hp and torque.

Anything i can check on my aem that might help me figure out my problem?
No... the downside of having a Supra anywhere in North America is having our American professional and non-professional automotive ideals and performance ‘know-how’ applied to Japanese cars.

I didn’t just pull all of what I said out of my ass… as I have already said…”You need to either lower your maximum boost, use a higher octane fuel and/or use colder range sparkplugs. Reducing sparkplug gap may help, but it's not the correct fix as everybody here assumes.” Especially if you are using 91 octane fuel.

i think its safe to say im not detonating!...sounds more like spark blowout!
Yeah right:rolleyes:....Call it what you want, spark blowout, miss-fire, pre-ignition or detonation…. there’s no argument that it occurs at it’s highest pressure or maximum boost. I should also mention that "denial" will also cause your engine to break?

Stock twins running and 18psi boost is considered excessive and will detonate using 91 octane… therefore any Supra with a single turbo is putting out an excessive amount of power regardless what the dyno numbers are.

The Aem is a blank engine management computer which uses outdated automotive technology. It’ll NEVER be perfect… It will only be as good as the end user’s ability to understand and ability to make the inputs as close to a stock ECU and running like it should be, while under real world conditions. Tuning a standalone for any turbocharged vehicle in one session isn’t gonna happen… especially on a dyno… because it doesn’t replicate “real world” conditions.

IMPO, I would check and see how much you can sell it for. No disrepect...you are in over your head...leave it to those who like to tinker. Get rid of the AEM and run a stock ECU with a piggy back VPC or a additional injector controller.

If you’re limited to 91 octane, you should get a meth/water injection setup... I prefer straight water myself, it's more convenient.

You should also be using newer designed fine tipped Platinum or Iridium spark plugs… not outdated NORMAL tipped plugs. Why? Sparkplug Manufactures have learned that their older sparkplug by design can actually shield the spark making it more prone to misfire. They’ve learned the old long heavy ground strap design can vibrate continuously thus causing inconsistent and erratic sparks…and I’ll add, that reducing the gap on NORMAL sparkplugs will only make matters worse.



There's no reason why anyone should gap smaller than .030”/.8mm. it’ll increase the chances for your plugs to foul.

 
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