[Kunz]

Hi there

Just a quick impression on how the car sounds now http://www.youtube.com/watch?v=FKLErNrR0MY

There are 2 slow / low load passes an 2 WOT fly-byes in 2nd gear up to the redline / limiter

If you compare to the upper video you hear the car sounds by far not as aggressiv as it used to with the 2.5"... And also by far not as furty. In my ears it sound more grown up now with the 3", even though i still love the racing sound of the 2.5...

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[Kunz]

Ok, i made several gtech-runs and the results are very consistant. The car has never been stronger and faster.

Obviously the set-up i got now really works well. I am sure it is not only the 3" exhaust but more a compination of all things. Ram-air-intake, washed-out k&n filter, rs-barn header, 100-cell race-cat and cat-back in 3" straight through... All of that running on e85

The power-curve is smooth with no dips and aggressive at the same time... Good torque and pick-up down low, no dip in the middle, high torque and long power above 4000 to redline with aggressive pick-up...

I really like it ???

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[Kunz]

Hi there

 

Unfortunatelly I didnt find the time to get this from my laptop to here electronicle, because I was up in the swiss mountains and didn't have internet-Connection there. But later I probably will post the curves right here.

Anyway, on the pic you see the comparison of one of my best runs with the 2.5" exhaust (red) and a run with the 3" (green) I just made.

You see a Little gain all over the revs, the biggest one below 3000rpm, while the curve itself stays the same. When I thought about welding the 3" I was pretty sure from what I experianced over the years with this car, the header and the cat will mainly be responsibel for the form of the curve. While with stock header installing a 100-cell-cat gave me big torque gains below 3000rpm, it produced a BIG and extremly annoying dip at 3500rpm and a slight loss in Performance at higest revs. Basicly with every cat-back-Setup I tryed... After installing the Header (RS-Barn, thank you) this effect is gone. While the gain is even bigger, there is no longer any dip or power loss, no, even a slight gain.

Obviously header and cat are very responsibel for "modeling" the curve on the car... after I have seen over the last experiments, it seems a bit like a garant, a "you-can't-go-wrong-with-everything-that-comes-afterwards". this is not absolutly true, I know... but it seems to come close and is a good base to work on... at least on my car.

 

A good indicater is always the passing times. from 40 to 100km/h in second, the car is some good 0.2 seconds faster...

 

Have a great day, til soon

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[flash]

given what i know about how E85 behaves, it would be interesting to see what the tuning is like.  because E85 makes more power than gasoline, especially at the low end of the curve, it may well be that you found out how to maximize the dual resonant intake manifold, and the 4psi boost it provides.

 

it is interesting to see that it still maintains the danged torque dip right smack in the middle of the cruising range (3k - 3.5k).  that makes for an unpleasant lag when you step on the gas on the freeway.  it is not unlike the losses i've seen on other similar systems though.  you gained low mid, only to have it dip right back down almost to where it was before.  it's annoying that every free-flow system does that.

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[Kunz]

Thanks for the feedback, Flash!

Well both curves are on e85, the only difference is the exhaust. The fueling is 14.5-14.7 cruising, progressivly getting richer up the load and the revs. Wot it starts at some 14 maybe at 2000rpm to climb to 13.5 at 4000, from there to redline it is between 12.8 and 12.5 which may seem a bit rich to you, but gave mi the best result and pic-up.

As for the "lag": furtunatelly you see it, but you do not feel it. After all it is not less there, it is stronger there also, but a little bit stronger below. The feeling is a strong and willing pull-through all the revs... I was a bit suprised to see this very little dip...

Compared to the one i used to have without the header and with a 2-pipe-system... This is really straight. And even more important: back then, the car was really sticky there, you could even hear, the gas exchange doesnt work right... Completly different now... Stronger than ever, everywhere... And with a nice pick-up everywhere, also in the so looking little thing there...

I tryed by the way to measure the "boost" in the manifold... I couldnt find it. Even with the ram-air, there was no real difference... For sure not higher pressure... Getting significantli higher output i thought to myself, it must mainly be about flow, not boost...

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[flash]

hmmm - E85 is supposed to be more like 9.8:1

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[Kunz]

The numbers above are just the reading of the wb-sond... Which measures the O2 after combustion... And not the amount of what-ever-kind of fuel.

So i should maybe rather say, i get the readings as if it was 12.6 on conventional fuel. The fueling for sure has to be much richer on e85...

I could rescale the lambda sond for e85 instead of fuel, but there is no gain in doing so.

If i let the stock lambdasond work to regulate the fueling on e85 (after installing bigger injectors and tune near right, so the ecu can correct the rest) the readings are 14.7 in cruising. This reading is for sure not correct concerning the mixture, but concerning the rest-O2.


I never calculated what mixture i actually drive, i just take the readings of the rest-o2 as said. To get an idea, where it could be, i can tell you that i use 48er injectors vs i think 32er stock injectors and i have above 4500rpm about the same injection times as on the stockers, which about (exept maybe the longer latency of the bigger injectors) gives 40-50% more fuel...

Btw: i drive the car with the stock lambda-sond deactivated to have no corrections of the ecu, but drive the map i programmed below 4000rpm / at low loads also...

I am sorry, Flash, i hope i could get it over with my lumpy english, even if it is not said that elegant...

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