Got a quarter mile time now for an ebwrks exhaust. So…
catless 2.75" eb vs stock downpipes with cats
2.75" eb catback vs stock 2.36"
$4500 vs free
Difference?
Nothing. Zero. Zilch. Nada. Ne riens.
Well almost. He picked up 3/100 of ET although that is because of his launch improving slightly (using JHM launch assist in his tune the last two times he went to the strip). As you can see the sixty foot time was three hundredths better than last time, and that was it for the track. His great exhaust actually COST him the better part of 1 mph in trap speed.
Anyway kudos to Mick for
A) hitting the dragstrip at all
B) posting these results (since they will likely hurt ebwrks)
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Fun night at the strip…
Posted by: Mickf29 (2524) on 2012-10-07 03:41:42
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Had a great time, was awesome seeing a friend go under 12.0 in his 1992 S4 for the first time! I had a decent night, but no times to brag about. I learned I am having a few issues: MAF is too low up top, I think a direct result of the exhaust being 2.75", just like the JHM unit as well, i am losing MAF up top when I am running no cats. Second this new clutch has a very high engage point and took some getting used to. I botched a couple runs and missed 2nd and once 3rd because I was expecting an earlier engage point, revved the engine too much and didn’t get the the shift in right. Got that smoothed out some. Lastly my shifter is really out of adjustment again. Just for sanity I have 2 other guys there with RS4’s compare, one had the same shifter and the other a Neuspeed, mine was totally notching up and not shifting well. Needs adjusted…again.
All that and I still managed to run the best i have ever run, but barely.Compared to my stock exhaust runs, my top end MPH was down slightly. My 1/8th times and speeds were very good though. So just as I suspected, the 2.75" exhausts with no cats are flowing well and generating awesome torque. but i am losing top end, MAF is too low. Going to try to work on this. Will pop the cats in and do some tests, see if that bumps up the MAF.
Here are the times of the 5 runs that weren’t too terribly mis-shifted.Interesting every run got better, as I got the clutch engagement point a bit better and worked my shifter. Shifter kept getting worse though as the night went:
Run # 2
60’: 1.840
1/8th: 8.234
1/8th MPH: 87.68
1/4: 12.727
1/4 MPH: 110.98
Note: Another sketchy 1st to 2nd shift
Run #4
60’: 1.824
1/8th: 8.182
1/8th MPH: 88.44
1/4: 12.648
1/4 MPH: 110.53
Note: Decent, just slow 1st to 2nd and 2nd to 3rd again
Run #5
60’:1.827
1/8th: 8.135
1/8th MPH: 89.11
1/4: 12.597
1/4 MPH: 110.59
Note:Car was getting really warm (235 oil temp). After this run let it sit for a while before last two runs below.
Run #6
60’: 1.803
1/8th: 8.055
1/8th MPH: 89.22
1/4: 12.493
1/4 MPH: 110.87
Note: Pretty good run, just felt like up top wasn’t fully there.
Run #7
60’: 1.794
1/8th: 8.021
1/8th MPH: 89.56
1/4: 12.404
1/4 MPH: 111.08
Note: Good run, shifts were as good as I could make them, launch was great. Not much more to do on my end, I was just out of breath up top.
interesting thing, when you compare this best run with the best run I had before on the stock exhaust (first numbers are EBWerks, 2nd number is Stock):
60’: 1.794 vs 1.830
1/8th: 8.021 vs 8.050
1/8th MPH: 89.56 vs 89.78
1/4: 12.404 vs 12.434
1/4 MPH: 111.08 vs 111.73
So its pretty clear to me the stock system allows for up top, the EBWerks and JHM and probably gonna make a wager and say any other 2.75" system you gain alot down low, but you sacrifice up top.
BTW temps tonight started at 73, and dropped to about 62 when we left. I started run with 1/3rd tank of gas. 92 octane V Power, same as always. Car and Driver weigh was about 3780lbs, about 20lbs lighter than last set of runs on stock exhaust. So in essence very much the same. Even air temp was about the same. I was encouraged each run was getting faster by about .1 each run. Also was nice to see the best 60’ time, 1/8th time and 1/4 time tonight, even though my speeds were slightly better on the last runs with stock exhaust setup.
Going to be interesting to see how my MAF and my Torque numbers behave when i drop in the cats and do some additional 3k-8k logs. See if they hurt the low end but bring up the top end, and see where the intersect point is for best overall. All said though, i am pretty happy with everything so far. I definitely have gained a ton down low. In fact today I did a 4th gear pull with another local out in the country from 60mph, and left him in the dust. By 7k rpm in 4th gear I was 3 car lengths on him he said. And he has JHM tune and pig pipes/H Pipe. Car is running damn good, and the way the power is delivering now, its going to be very good on lapping where you spend more tie down in the torque band.
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