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APU but feels rather Slow


Ulrik
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Maybe you can help me out here....

Iv had my car for 2 years now, when i bought it, it was all Stock.

And now its APU, but it feels rather slow....

Last year it was BPU+ with these parts:

 

Blitz SUS Airfilter Kit

Greddy BCC

Greddy 3" FMIC

Greddy 60mm Boost Gauge

Greddy 60mm A/F Gauge

Greddy 60mm EXT Temp Gauge

HKS 4" Ti Exhaust

HKS EVC 5

HKS SSQV BOV Kit

RMM 3" DP

TRD Twin Plate Clutch

NGK 3330 Spark Plugs (original gap)

 

Running 19 PSI (1,31 bar)

 

And now this year i have:

 

Greddy T78 Turbo Kit

BL 780cc Fuel System

HKS F-Con V Pro Gold (Tuned by HKS Pro Dealer)

Greddy Type-R Bov (stiff spring)

 

Greddy 3" FMIC

Greddy 60mm Boost Gauge

Greddy 60mm A/F Gauge

Greddy 60mm EXT Temp Gauge

HKS 4" Ti Exhaust

HKS EVC 5

TRD Twin Plate Clutch

NGK 3330 Spark Plugs (original gap)

 

Running 21 PSI (1,4 bar)

 

I didnt DYNO my car when it was BPU+, stupid of me....

I only had as referance when i raced with my friend with his Porsche 911 Turbo -01 (996, 420 hp).

 

We did alot of rolling starts and when i was BPU+.

And we were equal fast.

But now as referance we did the same again, when my car is APU.

So we raced again, rolling starts....

 

I was only a little faster ,maybe 1 car ahead of him tops...

Feel like i have 20-30 hp more then before....

Something must be wrong.... :blink:

 

At idle the RPM goes up and down, all the time...

And at high speed at high rpm, it feels like it missfires somewhat..

Should i maybe change to some colder plugs, and make the gap smaller then stock ?

Still have the same plugs since last year, the NGK 3330.

 

Something wrong with the mapping ?

Shoulde be since it was mapped by a HKS Pro Dealer....

 

I have the yellow 0,8 bar spring in the wastegate...and running 1,4 bar on the Boost Controller.

Gonna have the car Dynoed really soon...so we can see how much it makes...

 

Should i boost some more, or get some more parts then add the boost ?

Need new Cams ? (HKS 264 intake/exhaust)

Engine is still stock on the inside...

 

On these parts i have now, how much hp should i have on the wheels and how much in the engine ?

What do you say, any tips on what to do for more hp ?

 

Thanks Alot

 

// André

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What power did the T78 make at 1.4bar?

 

Not 100% sure what to think...

The one who mapped it, claimed it had 575 hp...not sure if he ment in the engine or on the wheels, but feels alot slower....

Then i asked for dyno pappers, but he couldent print them...

 

So, im going back there in a few days to get it Dynoed for real...

See how much it makes...because it should feel alot faster then bpu+ right ?

 

// André

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When you say it still has the same plugs from last year, do you really mean they are the same exact plugs that you have been using. Or are they the same model but new ?

 

Exact the same....should change i guess :(

But the car have not run that much since bpu+ and single...

Gonna change them within 2-3 days....

 

In addition to what Gamer asked, the erratic idle and misfire on boost might be a sign of a very rich map (this is what mine does on a base map).

 

Do you have an AFR gauge?

 

Yes i have Air/Fuel Ratio gauge....from greddy 60mm...

But im not sure it works like it should...since i bought it used......and not 100% its connected right...hmms

It seems broken, it keeps flying up and down, maybe i should get a real wideband meter ?

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Exact the same....should change i guess :(

But the car have not run that much since bpu+ and single...

Gonna change them within 2-3 days....

 

No wonder you have problems! Change them ASAP

 

Yes i have Air/Fuel Ratio gauge....from greddy 60mm...

But im not sure it works like it should...since i bought it used......and not 100% its connected right...hmms

It seems broken, it keeps flying up and down, maybe i should get a real wideband meter ?

 

When driving around normally thats exactly what they do :) The bit you should pay attention to is when you are under boost and at WOT.

 

Get the car in say 4th or 5th gear, start from 2.5k rpm and take it up to near the rev limit, while watching the AFR Gauge (actually, its probably safer to get a mate to!). when under full boost and throttle it should read 11.5 or less. If its more, take your foot off the throttle immediately.

 

Let us know how you get on (after the plug change!)

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Thanks for the great input homer :)

Gonna do that asap.....meeting a friend of mine that help me build the supra, he gonna help me with it all....

 

Do i need a better wideband meter ?

Iv heard they are poor, need a digital ?

 

// André

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Do i need a better wideband meter ?

Iv heard they are poor, need a digital ?

 

Do you know what the range of the gauge is and whether the sensor itself is wideband? A narrowband is next to useless as the 'important' area will be out of range.

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The GReddy gauge uses a widband sensor and shows values between 16.0 and 8.0, so should be fine.

 

So it should work fine ?

I dont need a AEM or Innovate LM-1 ?

Ill try and get the meter on film....since it seems very strange to me....

 

// André

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I presume the mapping of the T78 done with the old plugs too, which isn't too clever.

 

The Greddy should be okay if reading from 8 to 16. Swap your plugs, go for a drive and watch the afrs on boost\wot as mentioned, then let us know what you are getting :)

 

Will do, they are not exactly old, since i didnt have time to drive that much, but iv alredy ordered new plugs and gonna pick them up after work today...and have them changed really soon...

Not driving the car till i had them changed....

 

Ill let u guys know about the AF Ratio later...

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I presume the mapping of the T78 done with the old plugs too, which isn't too clever.

 

 

See this just wouldn't give me any confidence at all in the installer of the parts. Also the mapper should really ask what the upgrades were and what the state of the whole system is before he starts the job. Also and this will maybe get me a bit of stick but I reckon a very well setup stock twin BPU+++ system will feel almost as quick if not quicker than a basic APU system will, especially with an auto car. I don't think you are going to find huge overall performance increases (I don't mean the top power figure here but the whole system performance) with a basic APU setup. Toyota went twin sequential on this road car for a reason.

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See this just wouldn't give me any confidence at all in the installer of the parts. Also the mapper should really ask what the upgrades were and what the state of the whole system is before he starts the job. Also and this will maybe get me a bit of stick but I reckon a very well setup stock twin BPU+++ system will feel almost as quick if not quicker than a basic APU system will, especially with an auto car. I don't think you are going to find huge overall performance increases (I don't mean the top power figure here but the whole system performance) with a basic APU setup. Toyota went twin sequential on this road car for a reason.

 

Have you ever driven/ride in a APU supra with 600-700 bhp ?

The fun starts here....:innocent:

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Have you ever driven/ride in a APU supra with 600-700 bhp ?

The fun starts here....:innocent:

 

No but I owned a BPU+++ supra with an argued 450 ish at the fly and I now own an apu aristo with a fair few more horses than that and I feel the supra was effectively quicker and easier to drive (powerwise) than the aristo is. There are obviously times when the power is stronger in the aristo but across the rev range the response is better from the TT's and what you don't get at the top end you make up for by getting through the lower and mid range quicker. Also lets be fair here 600-700 bhp is not a basic APU setup is it? More like stage 2 or 3 or whatever they call it.

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Nothing wrong with the battery or the plugs...

But my A/F meter seem to be broken....gonna try a new one soon....i guess its just poorly mapped... :(

Gonna take it back in the next week i guess....and ask for dyno papers

 

// André

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Hey Andre, I hope you understood my reply to your PM. Your AFR gauge appears to be okay, I think you need to get it back to your mapper to explain why it's so down on power.

 

I'll be over in 2 weeks so will be happy to take a look at it for you

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