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Discussion Starter #1
Hi guys, I also posted this on the AEMpower forum to see if I could get some advice...


I have a 1994 Toyota Supra.


Right now, it's running stock coils, AEM CDI ignition, AEM EMS, Titan crank pulley, forged internals, 880cc injectors, T88, dual in tank stock pumps. I have an AEM wideband guage in the car.

I have the mixture nice and rich, the EGTs never go beyond 750c, ignition timing is very conservative ( I think )




I put in C16, 5 gallons, and did a bunch of runs today. The car pulls like nuts in 1st and 2nd gear, but as soon as I go into 3rd it feels like **** and hits a brick wall; will not accelerate. The weird thing is, on my LAST run where I did 1-2-3, I shifted late into 3rd and I think my clutch started slipping because I saw 6000 rpm, either that or I lit up my 345 drag radials...


This is at 1.4 bar the whole time. Please help me figure out my problem as I don't dare floor it on 94 octane gas because I'm afraid it's going to explode on me.

http://www.lr-racing.com/club43ma/1-2-3.stf ( Felt great on this run in 3rd, pulled like crazy )
http://www.lr-racing.com/club43ma/1stwot.stf
http://www.lr-racing.com/club43ma/2ndgearwot.stf
http://www.lr-racing.com/club43ma/3rdgearhighwaysucks.stf ( When I floored it in 3rd it just fell on it's face, car didn't even move and bucked a little, scared the **** out of me and I got off it right away
http://www.lr-racing.com/club43ma/wot2nd-3rd.stf ( again hit a wall in 3rd, lots of noise from the external wastegate, and almost 0 feeling of acceleration )


What I wonder is, when driving around normally I always get this small window of misfires when I transition into boost at around 4200-4500 rpms. I wonder if this has something to do with my problems shifting into 3rd. I haven't tried flooring it in 3rd at 5500+ RPMS, I have only rolled into it which seems to cause the car to not accelerate and buck a bit. Is it too much timing as the boost hits?
 

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Me and 2 other guys had the same issues. What it came down to was a bad wideband sensor. All 3 of use were running the FJO, but the FJO was giving false readings that seemed good. (11.5). Come to find out, at WOT we were dumping too much fuel but the WB said other wise. At idle the WB read perfect, but at WOT the readings were way off. We all discovered this during a dyno day and noticed how pig rich all of us were when running the Motec WB dyno sensor. 1st and 2nd will pull fine and hard, but once you get any type of good load on there like in 3rd, it became apparent and started falling on it's face misfiring.

Go to a dyno or borrow a buddy's WB to make sure yours ss working properly. One thing that was a dead give away was no matter how much fuel I added, the A/F readings didn't change one bit.
 

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Discussion Starter #5
Go to a dyno or borrow a buddy's WB to make sure yours ss working properly. One thing that was a dead give away was no matter how much fuel I added, the A/F readings didn't change one bit.

I don't hear any misfiring though in 3rd, it sounds fines! That's the weird part....


The WB is fine I just checked it this morning, it will react to adding lots of fuel at idle or removing it


Argh... my widebody Supra runs like a raped ape in 1st and 2nd, but 3rd is like an 88 Corolla. :(
 

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Please get the car to a tuner that knows what he is doing!!!!

Tim


x2.

your logs are leaving out some very important parameters.... if your not logging the good stuff, makes me think the tuner is a noob. My guess is it's loading up on fuel... but without a log of the WB... who knows.
 

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It's a different misfire with loads up with fuel. The behavior I had was that it would just fall on it's face during a pull in 3rd. My bet it is somethign with fuel.

Etiher too much or not enough. I can't view the logs at work ,but what does your fuel pressure read? When you say you have the mixture nice and rich, there is such a thing as too rich. At idle the WB will respond to adding and removing fuel, but at WOT it's completely different. Just as an experiment, start taking out fuel where is takes a dump. I did that when my WB went out before I verified it on the dyno.
 

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Discussion Starter #8
x2.

your logs are leaving out some very important parameters.... if your not logging the good stuff, makes me think the tuner is a noob. My guess is it's loading up on fuel... but without a log of the WB... who knows.

Last tuner killed my last built motor...


I'm taking it to the AEM master on June 1st, John Reed, but I'm trying to figure it out a little for myself before I go down there so he doesn't look at my AEM tune and slap me
 

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I will take a look at the logs later or tomorrow but looking at your ignition map you do not have enough timing in it for C16. The burn of C16 is a lot different than pump gas (91, 93)
 

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Discussion Starter #12
Wow, 9 degrees of timing on C16 and 1.2 bar FTL. "Nice and rich" too? Bring it on over to Mr. Reed ASAP.


Hell yes I am going to, like I said last time I had a "tuner" here work on it it blew up... so I have it setup so that I KNOW I can't blow it up

It pulls fine from 6000+, and runs great under 4500... but 4500-6000 it just hesitates and doesn't go anywhere :(
 

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Hell yes I am going to, like I said last time I had a "tuner" here work on it it blew up... so I have it setup so that I KNOW I can't blow it up

It pulls fine from 6000+, and runs great under 4500... but 4500-6000 it just hesitates and doesn't go anywhere :(
You are still driving down in your Supra when I take mine to get dynoed and such Jason? Next Friday remember

Duane
 

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youre not running enough timing!
i had a similar problem with my car. ive dug all over the place, thought it was a mechanical problem, checked if my AEM box was bad. it turned out the car just simiply wanted more timing! start adding it in increments of 1 little by little and youll notice the car will wake up.
 

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Me and 2 other guys had the same issues. What it came down to was a bad wideband sensor. All 3 of use were running the FJO, but the FJO was giving false readings that seemed good. (11.5). Come to find out, at WOT we were dumping too much fuel but the WB said other wise. At idle the WB read perfect, but at WOT the readings were way off. We all discovered this during a dyno day and noticed how pig rich all of us were when running the Motec WB dyno sensor. 1st and 2nd will pull fine and hard, but once you get any type of good load on there like in 3rd, it became apparent and started falling on it's face misfiring.

Go to a dyno or borrow a buddy's WB to make sure yours ss working properly. One thing that was a dead give away was no matter how much fuel I added, the A/F readings didn't change one bit.

Good suggestion, but I think the owner should get the car tuned first. My FJO works great - you can also tell if you are running rich by reading plugs or looking at the exhaust during a WOT pull. If you're running rich enough to slow a car down that much, you WILL notice it.
 
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