American Racing Headers + 373 gears + MCS suspension = Awesome Viper

[KB Viper]

Since i have the coupe i only had one suspension setting and it was harsh as a DD so Dan installed the MCS stage 2 suspension and the car rides so much smoother. He also lowered it 1/2 inch (carbon aero package stopped me from lowering 1 full inch).

[AbsolutHank]

Wow that's an impressive mod list! Congrats!

[FLATOUT]

Dyno numbers?

[Shooter]

Dyno numbers?

Probably be pretty skewed with a 3.73 rear end.

[FLATOUT]

Probably be pretty skewed with a 3.73 rear end.

By 10 but wanted to see if it was dumping fuel like the other gen Vs on factory ECU's

[Nine Ball]

Car sounds wicked. I won't be doing headers until a tune for them becomes available. The local cars here that have done them run horribly rich and don't pick up any power with the stock tune.

[IndyRon]

Nice Setup! You should be crossing the traps at peak HP also which is optimal for 1/4 racing.

Car sounds wicked. I won't be doing headers until a tune for them becomes available. The local cars here that have done them run horribly rich and don't pick up any power with the stock tune.

As far as the factory tune, that is interesting. With my car, the headers really leaned the car out. I'm curious as to the differences that were programmed in for the Gen 5 cars or if my car was just unusual. I seem to remember Toddy at BBG stating that power adders tend to lean the Gen 4's out.

[Nine Ball]

Nice Setup! You should be crossing the traps at peak HP also which is optimal for 1/4 racing.



As far as the factory tune, that is interesting. With my car, the headers really leaned the car out. I'm curious as to the differences that were programmed in for the Gen 5 cars or if my car was just unusual. I seem to remember Toddy at BBG stating that power adders tend to lean the Gen 4's out.

Most cars do lean out, when you install a better flowing exhaust system. But, the Gen 5 must have some tune difference that sends a bunch of fuel when it sees something off. Safer, but also makes less power. Also, "power adders" typically means turbo, supercharger, nitrous. Not headers, those are just called "bolt-on mods".

[Voice of Reason]

Car sounds wicked. I won't be doing headers until a tune for them becomes available. The local cars here that have done them run horribly rich and don't pick up any power with the stock tune.

Agreed. My dealer said they installed headers and only picked up 20 hp, mostly below peak, because it went so rich. I really want headers but not without a tune.

[Jack B]

I have a wide band on my car, therefore, the following is some accurate data"

1. In general, some G5 cars run rich at wot. That robs some hp

2.With balengers, my car does not run overly rich at wot and runs lock sync at 14.7 in closed loop.

Car sounds wicked. I won't be doing headers until a tune for them becomes available. The local cars here that have done them run horribly rich and don't pick up any power with the stock tune.

[IndyRon]

I have a wide band on my car, therefore, the following is some accurate data"

1. In general, some G5 cars run rich at wot. That robs some hp

2.With balengers, my car does not run overly rich at wot and runs lock sync at 14.7 in closed loop.

Jack, this may not be the thread for it, but if you have any pulls with data recorded pre/post headers, feel free to post them up. I have a few dyno runs with A/F overlays to compare as well. It would be interesting to compare how the G5 and G4 respond.

[1Koolasp 16ACR]

I'm With You, On That One Nine Ball, Not In The Mood To Spend 5 G's, With Poor Or No Results , Beside It Sounding Louder, A Good Tune And Some Before And After Dyno Numbers , Then Decide !!!!

[FLATOUT]

I have a set of ARH's sitting in my garage waiting for an ECU

[98intrigue]

Sounds awesome!

[FLATOUT]

Even the basic ECU, the Gen IV cars have had for awhile. We aren't just talking about actual tuning which is most important, but even something to keep the factory ECU from dumping fuel into the tune when adding headers.

When you currently add headers to a gen V you are seeing some gains down low, but up top the ECU starts doing some funky things which I personally don't want going on in my car for an extended period of time. The factory race ECU's on the Gen IV's kept this from happening and you did see actual gains from mods like headers.

Ralphs car see's the same gains from these mods that the Gen IV cars did, unfortunately he's the only one that is getting to enjoy it.

[Voice of Reason]

KB I hope my comments didn't come off the wrong way. You've done pretty much exactly what I want to do to mine, including the gears. You kept the stock mufflers right? How is the highway drone compared to 100% stock?

[FLATOUT]

KB I hope my comments didn't come off the wrong way. You've done pretty much exactly what I want to do to mine, including the gears. You kept the stock mufflers right? How is the highway drone compared to 100% stock?

Absolutely and me too, wasn't trying to be a dick was actually interested to see if you guys had any before and after numbers to see if the factory ECU was doing what others have done in the higher RPM's.

[Vipes]

Daaaaamn, doesn't get any better than that!

[tiki240]

Price tag for all mods done?

Love the way it sounds.

[SteveDoten@ARHeaders]

Kris, nice write-up! I've seen that road before with a ZR1 doing similar maneuvers.

[Jack B]

If kbviper approves I will post a pull in this thread, otherwise, I will start a new thread.

[Nick@A.R. Headers]

Kris, I really appreciate you choosing ARH for your Viper and thanks for posting your thoughts. I just wanted to mention, our ARH cats couldn't be any Greener if leprechaun's made them. They are 200 cell but with a high loading of precious metals have proven to be pretty efficient. They are 49 State legal and can handle abuse extremely well. In fact, the substrate in our latest version of cats can handle over 2800* of temperature. Their ability to prevent a 420/430 code is as good as any brand out there but with long tubes there's still a possibility. Of course with tuning those possibilities go away. Also, on our headers, we place the front O2's in the collectors so they can read all 5 cylinders, not just one cylinder.
Lastly, horsepower will be made with our header system regardless of tuning. I've yet to see the air/fuel any Gen 4 or 5 change to the point where the headers didn't dramatically improve performance untuned.

Thanks again Kris and have a great summer!

Nick

[Jack B]

The following is a run from 3000 rpm to 6400 rpm in second gear. The ambient air temp was approx 50 degrees. I consider this an almost perfect a/f curve and is very similar to my G2 after being tuned with SCT. The run was made with ESC off. I have a second identical pull at 70 degrees air temp. That graph shows a little richer a/f curve, however, that is the same thing that happens on a stock G2, the factory fattens the a/f as the temps increase. This is almost counter-intuitive, however, there is some reasoning behind the scheme.

What shocks me about this curve is how much timing is pulled across the whole curve, especially from 3500 to 5500. If we do not encounter knock-Retard (KR) there is a lot of HP to be had in the center of the rpm band.

2013 SRT 2nd Gear-50 Deg 4-8-2014 copy.jpg

[IndyRon]

Jack,
Thanks for posting that up. I don't have timing advance on mine but do have A/F ratio with subsequent runs.

First graph is stock (blue) vs. Gen5 int/Mopar PCM (red) vs. Int/PCM/Headers (green). You can see the A/F ratio with the PCM slightly richer at the bottom but leaner at the top. Then with headers, leaner everywhere. The headers run was pull 8 so the computer had a chance to adjust.


Now, this graph is boltons including headers during subsequent back to back runs no shutdown or cool-off. Runs are in numerical order 5, 6, 7, etc corresponding to subsequent runs. The car is pulling fuel with each run but it is targeting a different baseline it seems vs. when it was on stock manifolds which is confusing to me. Whether the car has headers or not, I would think the PCM wants to see 12.xx A/F at xxxx RPM regardless of modifications, although it is obviously pulling fuel with subsequent runs even though I'm over 1/2 point leaner than with the same PCM and stock mani's.

[Jack B]

Interesting - a few observations:

1. My pull was on the road, therefore and whole bunch of variables are added. In addition, the sensor on my car is in the collector, whereas, you are using a tailpipe sniffer. Even with those differences, the a/f is close over 5500 on my G5 and your G4.

2. There is a definite correlation in a/f between our cars, however, your car shows extremely lean at max torque, I would think knock-retard is pulling timing on your car. Max torque likes a little richer than max hp. If you drop the smoothing you will probably see the hp dip near max torque.

3. Without digital intervention, the headers should lean the a/f once you go open loop.

4. It looks like your operator did not use the dynojet brand of a/f logging, that is good since they suck. You cannot turn off smoothing with the embedded system.

5. It does not matter now, however, you lose a lot of detail with a 5 smoothing. You will probably gain some hp (on paper) if you drop the smoothing, plus, it tells us more about the engine's power output.

Jack,
Thanks for posting that up. I don't have timing advance on mine but do have A/F ratio with subsequent runs.

First graph is stock (blue) vs. Gen5 int/Mopar PCM (red) vs. Int/PCM/Headers (green). You can see the A/F ratio with the PCM slightly richer at the bottom but leaner at the top. Then with headers, leaner everywhere. The headers run was pull 8 so the computer had a chance to adjust.


Now, this graph is boltons including headers during subsequent back to back runs no shutdown or cool-off. Runs are in numerical order 5, 6, 7, etc corresponding to subsequent runs. The car is pulling fuel with each run but it is targeting a different baseline it seems vs. when it was on stock manifolds which is confusing to me. Whether the car has headers or not, I would think the PCM wants to see 12.xx A/F at xxxx RPM regardless of modifications, although it is obviously pulling fuel with subsequent runs even though I'm over 1/2 point leaner than with the same PCM and stock mani's.