Tuning Resources?

jasontiff

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Does anyone know of any good introductory resources for tuning? I want to read up on what all is involved when analyzing data from the car. It's a steep learning curve but I want to get a grasp on that stuff so I'm not constantly relying on a friend or paying a tuner to modify my cards every time Texas decides to shift the weather by 40˚. I know I won't be a pro but I'd like to at least be able to comprehend what I'm seeing on-screen when I plug in my laptop and be able to make little adjustments on my own.

I know I could call/PM/email Sean or Dan directly, but I thought it'd be good info to have out on the board in case someone else wants to blow their car up like me :D
 

Dom426h

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I have read though this
Amazon.com: How to Tune and Modify Engine Management Systems (Motorbooks Workshop) (9780760315828): Jeff Hartman: Books

and am planning on eventually getting to these:
Amazon.com: Dyno Testing and Tuning (Performance How-To) (9781932494495): Harold Bettes, Bill Hancock: Books

Amazon.com: Engine Management: Advanced Tuning (9781932494426): Greg Banish: Books


I only read this stuff for general knowlege. I simply like being able to have an intellegent coversation with my tuner so i dont have to "take his word for it".
I'll prob always leave my tuning to proffesionals like DC performance, ViperSpecialty, or RoeRacing as they have already tuned hundreds of various vipers. Why should i try to reinvent the wheel?

I prob know enough to tune, but it would take me several dyno sessions and itterations that would cost me alot of $$ and wear&tear on my viper. I dont mind paying a pro to do it right the first time.
 
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jasontiff

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IMO if the tuner did his job, there should be no Reason to change tunes..

Weaver did a helluva job tuning my car in September, but now it's January. Humidity and temperature have changed, so cooler, denser air makes its way into the motor, leaning it out a little. In the summer months, the hot, humid air will make it run rich. With the temperature swings, it needs a little street tuning here and there. My car has recently dropped to 10mpg with just normal driving, so I need to look into it and thought I'd start with fuel tables and the tune.

Thanks for the book links; those will be ordered shortly. I, like you, would just like to have a firm grasp on what's going on when the car is being tuned, and when I look at the various tables in whatever program I'm running I'd like to be able to comprehend what it's telling me. I'm not looking to be a tuner either, but if I get some fluttering at a certain RPM, I'd like to be able to know what's going on and possibly correct it.
 

martyb

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You have an a/f guage Jason? I honesly didn't notice much difference going from 85 outside to 45. Leaned out a tad, not much though.
 

white out

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It's not Viper based, but google romraider. It's open ecu tuning forum for turbo Subarus and has a very good intro into tuning info.

Nick
 
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jasontiff

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You have an a/f guage Jason? I honesly didn't notice much difference going from 85 outside to 45. Leaned out a tad, not much though.

That I do.

It's not that I expect detonation or drivability changes with the weather, but every now and then I get little stutters in the RPM band and I'd like to know enough to try my hand at tuning it out. I'd like to be as knowledgeable about my car as possible.
 

GTS Dean

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Jason,

The Viper JTEC has 2 different maps - Closed Loop with adaptive control and Open Loop with flashed tuning. Closed loop adaptive will automatically make adjustments to varying atmospheric conditions and the way you drive. However, once you get above about 3000 rpm in moderate to heavy load conditions, the car runs on the baseline flash tune and you lose input from several of the sensors. Piggy-back systems like the VEC allow you to tailor the open loop parameters.

Spark advance and injector pulse width will vary based on air density and moisture. If you're running a CenTex summer tune, the density altitude at that time was likely somewhere between 2500-4000' and Super Dave pulled a lot of timing and fuel out. In dry, dense air, you have a low density altitude so you can run more advance and fuel pulse width to make the most from more oxygen in a cubic foot of air. Right now in NB, it's 47F, 38% RH, 30.1" Hg. The actual elevation is 640', but the air density is minus 78' - and that's what your motor needs to be tuned for. FYI - Just walking back inside and up a flight of stairs, the DA rises to almost 1500' with 23 degrees F increase, but the humidity is 10% lower indoors.

Buy yourself one of these: Kestrel 4000 Pocket Weather Tracker – Nielsen Kellerman
 
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BOTTLEFED

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There's some good intro stuff in the Gen2 tuning forum. DY's tutorial's are good reference too (if they're still on there):dunno:
this is where I learned a lot on tuning with the VEC
very good info and I think it is all still in there

jason, do yo have the VEC2 or 3?
 
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jasontiff

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this is where I learned a lot on tuning with the VEC
very good info and I think it is all still in there

jason, do yo have the VEC2 or 3?

I have a VEC2 and I'm apparently ******** cuz I didn't spot the tuning stuff. Does anyone have a second to hit this thread up with a link?
 

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