Ws6jason

Hey guys,
I just want to report that after LT Headers, ORY, EGR / A.I.R. Delete, SLP Air Lid, Loudmouth Cat Back, and SCT Tune, I am running 29.75 MPG average with easy acceleration and cruising at 1700 RPM...
2000 A4 WS6 with stock .323s
Is this about right? I've encountered several nay sayers regarding these numbers. I'm thinking it's the 1700 RPM "Sweet Spot" that this car likes to run, efficiency wise...

HCI2000SS

iTrader: (2)

So 29 mpgs all highway at 1700 rpm? If so I can see that. The intake and exhaust mods are allowing it to breath better. It's when you get into things like forced induction, cams, higher compression, fuel system changes and upgrades, etc...thats when mpgs start to really dive.

Btw I see you're in MI. Whereabouts?

99 Black Bird T/A

iTrader: (4)

Sounds within reason to me for highway miles.

Stock internal motor & stock gears, with free flowing exhaust, less restrictive intake track & a good tune is probably close to ideal for best mpg highway if one keeps the foot light on the gas pedal.

My 02 Z28 stock, 2.73's 242,000 miles gets 27.5 mpg consistently.

​​​​​​The 99 TA M6 with basic bolt on's & stock 3.42's got 32.5 mpg. Same 99 TA w / heads & cam, LS6 intake, LT's & 4.10's got 27.5 mpg. Same 99 T/A with 416 etc gets 20 mpg. Notice as the mod's & hp went up mpg dropped

Friends 00 FireHawk M6 basic bolt on's gets ~31 mpg highway.

Ws6jason

I'm thinking about doing a cam / intake swap next summer. I want something with more low end power to try to get into the 11's in the quarter without losing too much mpg. Any suggestions?

Ws6jason

Location is Onaway, by the way...

HCI2000SS

iTrader: (2)

You will lose low end power with a cam swap, but obviously it more than makes up for it in the 1/4 mile. A set of gears and a stall will really wake it up though

Ws6jason

Any suggestions to get me into the low to mid 11's without dipping under 20 mpg average?

HCI2000SS

iTrader: (2)

Regardless of what mods you do i'd get a good aftermarket stall. I can think of one way that will practically guarantee mid 11's and won't change your gas mileage one bit....nitrous. A simple 100 shot and a sticky tire would easily do it

Ws6jason

What do you think a 3600 stall, tires, and .373s would put me at, quarter mile and mpg?

Ws6jason

And maybe a mild cam....
I'd like to shy away from the nitrus, due to engine life, if possible. ..

HCI2000SS

iTrader: (2)

1/4 mile with a set of drag wheels maybe 11.9 if you're really lucky. That's assuming you're at full weight basically. A 3600 stall will drop the gas mileage a little but no way will it be close to 20 driving like you do when you got that 29 mpgs. It will affect city mileage more than your highway

HCI2000SS

iTrader: (2)

What do you consider a mild cam?

Ws6jason

Is this estimate for the stall only, or with the gear change / cam swap as well? I'm assuming that at the consistent 110 mph run I'm doing now, I should be breaking 12s?

HCI2000SS

iTrader: (2)

I'm talking with the stock cam, gear change and 3600 stall. Your trap speed will go up a few as well with the stall. My buddy went from 108 to 111 with just a FTI 3500. What tire and wheel setup are you running now?

Ws6jason

I'd like to have a daily drivable car, but I'm not really sure when it comes to lift / duration numbers really...
Shitty idle is always a good thing, as long as drivability is ok... lol

HCI2000SS

iTrader: (2)

A big part of having good drivabilty comes from having a good tune. Of course that's subjective as well. A cam will definitely drop the fuel mileage too

bigbomber5

I'm not talking from experience but rather years of reading other's testing and results, for an automatic going from a 3.23 to a 3.73 doesn't yield any real gains. Your "seat feel" may feel like the car pulls harder, but in actual 1/4 times any increase is negligible.
However, upgrading the stall, lets say to a 3600 or even 4000, is probably the single biggest upgrade a beginner *with an a4* can do to improve quarter mile times. If you plan on getting a cam now would be the time as a custom cam and stall compliment each other very well.
Hope this helps

bigbomber5

By "beginner" I mean the the early stages of beginning to mod your car. I could of used a better word

Ws6jason

Any advice helps greatly. I appreciate all the feedback / help I get here. I am trying to build this car as a daily driver in stages. First was giving it some air to breathe and a tune, which helped greatly. Next will be either a cam / gear, cam / stall, or all three upgrade...

HCI2000SS

iTrader: (2)

Also I just want to mention that running nitrous on occasion won't affect the engine life to any appreciable degree. It has to be done right of course. I run it now on my Camaro and I ran it on my old Mustang