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When you say "stock rear gearing", what is the ratio? There is more than one "stock" ratio. The A4s had 2.73 and 3.15s available. I had 3.15s and went with a built 3.42 and it feels just about right. Some like taller gears but I don't think I'd got beyond the 3.73 if your primary use is on the street.
I'd be looking for your missing MPH on motor first... That's stock C5 mph. What was the DA? Has the engine been data logged and tuned? Good plugs/wires etc etc? Maybe the converter is a bit inefficient going down the track. The MPH gain is good on spray.
Before you start changing parts, I'd really analyze what you have and get it in tip top shape. Unless you are running at 6000'+ DA, I think you are 4-5 mph off minimum...
After you get it where it should be, then next line of progression would be good tires, more converter, 3.42s, heads/intake etc. $$$$$
Not sure of DA, but it was a hot and humidity day, so I wasn't expecting to break any records lol.ran 8 n/a times then let it cool for about an hour then ran 2 nitrous passes.
Yes cars tuned,all new plugs/ wires ,oil pump water pump/ all seals ect. Mechanical the car is fine.
My tires are 7 years old and I gotta set coming now but I still think it should of been faster than that. I plan on going back this Friday for TNT weather permitting so I'll have something to compare to.ill keep ya guys posted, thanks again for all the advice.
Well.... 107 mph is about 300 rwhp so... If you think your cam/bolt ons/converter LS1 is all tip top, then I don't know what to tell you. Unless your DA was REALLY bad.... Like 5000-6000'+ DA... That or your converter is very inefficient on the top end of the track and slipping away your HP.
My wife's bone stock G8 with only a canned tune ran 13.05@107 at +400' DA, that's at 4185lbs race weight and still the stock air filter in it. I never dynoed it but most of them are around 300-320 rwhp with the same canned tune.
Personally, I'd buy some dyno time and really go through it with a fine tooth comb. Ohm out your spark plug wires, make sure the resistance is low on them so you're not getting any misfires you can't feel but cost power, check for knock retard and really look the tune over.
Even on a +3000' DA day, a car setup like yours should be running 111-114 mph. Loose converters can kill MPH though if they are too loose up top. I had a converter that was measuring 11.5% slip in the traps, I changed converters to another custom unit, still measured 11.5% slip, yet ran 5 mph faster. Car felt exactly the same.
Well.... 107 mph is about 300 rwhp so... If you think your cam/bolt ons/converter LS1 is all tip top, then I don't know what to tell you. Unless your DA was REALLY bad.... Like 5000-6000'+ DA... That or your converter is very inefficient on the top end of the track and slipping away your HP.
My wife's bone stock G8 with only a canned tune ran 13.05@107 at +400' DA, that's at 4185lbs race weight and still the stock air filter in it. I never dynoed it but most of them are around 300-320 rwhp with the same canned tune.
Personally, I'd buy some dyno time and really go through it with a fine tooth comb. Ohm out your spark plug wires, make sure the resistance is low on them so you're not getting any misfires you can't feel but cost power, check for knock retard and really look the tune over.
Even on a +3000' DA day, a car setup like yours should be running 111-114 mph. Loose converters can kill MPH though if they are too loose up top. I had a converter that was measuring 11.5% slip in the traps, I changed converters to another custom unit, still measured 11.5% slip, yet ran 5 mph faster. Car felt exactly the same.
Making an appointment with another tuner to look things over on the dyno. I have new granatelli plugs wire with br7's that I just checked with the multi and they're all kosher. Plugs look great, I went through 4 new sets dialing in the nitrous. I slapped the hp tuners back on and monitored for knock....nothing. the only thing I didn't do was tune it (it was road tuned) but hopefully this new guy can get it squared away or find the issue.
Cordova dragway Illinois, I'm from Iowa, davenport area but that's the home track lol
Looks like your DA was around +1600' on 8/15... Not THAT bad... not great, but not bad for Summer air.
I wonder if your converter is eating it up....
Get it on the dyno and lock the converter and see what kind of power it makes... I'm guessing by your MPH you are around 320 rwhp... maybe a bit more on the dyno since the converter will be locked but... You're still missing 50+hp somewhere judging by the mph.
I actually ran 8-14 but posted on the 15th, but I do have an appointment this coming Saturday with an "LS guru" so hopefully it's tuning related and not mechanical.
you must have something holding you back a cousins bone stock, stock tire 01 c5 auto ran 13.2x / 13.3x all day every day best run was a 13.1x
cam stall and tire should of put you well into the 12's
how are you controlling your nitrous? is the car running the nitrous tune all the time or you using a timing controller for when the nitrous is activated?
you must have something holding you back a cousins bone stock, stock tire 01 c5 auto ran 13.2x / 13.3x all day every day best run was a 13.1x
cam stall and tire should of put you well into the 12's
how are you controlling your nitrous? is the car running the nitrous tune all the time or you using a timing controller for when the nitrous is activated?
Running a lingenfelter LNC 2000 to pull timing.
I never made it to the tuner to have it looked at, I had a massive cluster f*!# at work and it was forced to the back burner. I'll post as soon as I find something out.
08-15-2015, 12:48 PM
finally made it to the track..
