JeepLab Prodigy Install LIVE

[boosted1]

Wes, why does your dyno chart show a loss of power, I understand the goal of midrange power, but I cannot understand why the prodigy power line dips under the stock line.


Also, can you give your position on axle gearing with dynos?


What tranny gear was prodigy's dyno done in?

When the vehicle is turbocharged, load is a huge factor. Graphing the lower RPM band is the most difficult. We ran the vehicle in 4th gear and slowed to the lowest point we could maintain a wide open throttle pull. So picture yourself in 4th gear and slowing down to like 2k and then give it wide open throttle. Not really ideal...
We use the dyno as a tuning device to hold the vehicle stationary. We then make adjustments while recording data from the vehicle and the dyno. This helps determine what adjustments are needed next. When its all done the street is where the fine tuning comes into play.

We used 4th gear for our pulls and also tested with 3rd gear. They were close enough where it didn't matter.

As for axle gearing on dynos, I personally have not seen this as a real issue. When I am taking the time to dyno a car I would start with a baseline, make the modification and retest to see the results of the modifications. If you are looking to compare something then the variables need to remain the same all the way down to how they are tested. What gear they are driven in, tire size, weather etc..

Gear ratio just changes how quickly the engine pulls through the RPM band. A gear change can deliver faster acceleration but will also get less fuel economy as it cruises at a higher rpm on the hwy. Turbochargers like load and I find ratios closer to stock work best. Over gearing may deliver adverse affects like poor fuel economy and surging on the highway.

Typically over gearing is done just to make up for the overall lack of power. If the Jeep performed great stock and you changed the tire size why wouldn't you just install the gear that puts you closest to stock? Choosing a different gear than this could give improved acceleration but would also change the rpm at cruise. The reason the performance went away is due to the weight of the tire and wheel combination. To get the performance back you will need more power.

[Snarf77]

Gear ratio just changes how quickly the engine pulls through the RPM band....

Typically over gearing is done just to make up for the overall lack of power. Choosing a different gear than this could give improved acceleration but would also change the rpm at cruise. The reason the performance went away is due to the weight of the tire and wheel combination. To get the performance back you will need more power.

Moving through the RPM band faster has an effect on power at the wheels; the significance of the loss is to be debated and could be a non-issue with regards to this level of power.

Higher numerical gear ratios are also used to increase crawl ratio off-road. That was one of my goals, especially with my manual trans. The higher the rpms when crawling..the smaller the the movements for a given throttle input. This also helps me into that midrange power band where my turbo shines.

Luckily I've had no highway surging of any kind; the highway driveability has been massively improved over stock.

Do you envision separate tunes for Stage 1, Stage 2, and eventually Stage 3 systems?

[UselessPickles]

When the vehicle is turbocharged, load is a huge factor.

We used 4th gear for our pulls and also tested with 3rd gear. They were close enough where it didn't matter.

These two statements seem contradictory to me, when talking about a dyno pulls on a simple inertia dyno. Jesse's Girl definitely produced very different results in 3rd gear vs 4th gear.

Wes - are you using one of the much nicer dynos that can dynamically change its load to maintain a controlled/constant rate of acceleration during your dyno pulls? If yes, then we'll never reproduce those results on a simple inertia dyno.

[Snarf77]

If only dyno runs were free we'd have everyone get on a dyno to get more and more data! My runs took from 8:45 am until almost 11am. It is a time and financial commitment.

But seriously- I'm with Ross noting that stock performance is fairly well known. Sure..it may be a bit different on one dyno vs. another but the data has been corrected. I also used the same dyno brand to keep it as close to an apples-to-apples comparison.

I will run Jesse's girl again after a new tune is released and maybe after I get a more free-flowing exhaust. From what I've read and some advice I've received; it should help the entire charging process.

[NOLAjeeper]

As soon as prodigy ships my stage 2 upgrade and I receive it in the mail. I'll be getting it installed and have some pre and post stage 2 dyno runs. I'll do my best to video document the dyno runs. And share it with the JL community. I hope Dan can ship it out this week.

[JeepLab]

As soon as prodigy ships my stage 2 upgrade and I receive it in the mail. I'll be getting it installed and have some pre and post stage 2 dyno runs. I'll do my best to video document the dyno runs. And share it with the JL community. I hope Dan can ship it out this week.

That would be AWSOME. A cross reference would be great.

Pickles, what do you say to dynoing your rig to give a stage 1 number?

[boosted1]

Good morning. I am Wes from Prodigy Performance. I am reading these forum posts and I am very concerned regarding the translations here. Our dyno numbers are not altered in any way. Why is there not a graph from the same vehicle, on the same dyno before and after. Also the SC guys should have the same. Then all three should be compared with the same correction factors on the same dyno etc. This should be the only way to make a comparison. Dyno runs with anomalies should be disregarded and run again. They certainly should not get posted. This only leads to misconceptions regarding the products.

The baseline should be set and there must be consistency to even begin to make a valid comparison. Dyno results without SAE correction are worthless. Choosing the highest manipulated number is a no no. We have never manipulated dyno numbers and we currently hold all power records for the JK Wrangler.

2007-11 350+ RWHP and over 400lbft of torque @ 12psi
2012- present 360RWHP and 370+lbft of torque @ 9psi

I would like to answer any questions you guys may have. Let me know!

[UselessPickles]

Then all three should be compared with the same correction factors on the same dyno

Ross: The RIPP (Black Betty) and Magnuson (Sweat Pea) were both run on the same dyno, weren't they? Any chance we could get Jesse's Girl on that same dyno?

I would like to answer any questions you guys may have. Let me know!

Where is the "Huge low end power" that your brochure boasts?

[JeepLab]

Ross: The RIPP (Black Betty) and Magnuson (Sweat Pea) were both run on the same dyno, weren't they? Any chance we could get Jesse's Girl on that same dyno?

Betty's stock dyno is at one location, Sweet pea is at another. They are almost 2 years apart.

Their "After" dynos were done at their respective locations, and then again at the same time on the same day at the final dyno location. (most recent)

Im trying to arrange to have a stock Pentastar JK dyno'd at the same location that JG just did the dyno at.

[UselessPickles]

Im trying to arrange to have a stock Pentastar JK dyno'd at the same location that JG just did the dyno at.

If a stock Jeep on that dyno produces results nearly identical to your existing stock results, then we know that stage 2 dyno results from that same dyno are reasonably comparable to the supercharger results you have.

If the stock results there are significantly different, then you really need to put Jesse's Girl on the same dyno as your most recent RIPP vs Magnuson dyno runs for a valid comparison to the superchargers.

Does Jesse's Girl's 4.88 Gearing shorten the power band?

Shorter gearing does reduce dyno results when an acceleration "sweep" through the rpm range is used to record the results. How much it reduces the results depends on how fast the acceleration sweep is, the difference in gearing, and the amount of rotational inertia in the entire drivetrain prior to the axle. I would NOT expect the 4.88 gears to account for a majority of the discrepancy between Prodigy's numbers and JeepLab's numbers.

I suspect a difference in dyno type/calibration is the main culprit. For example, if the dyno has a smaller/lighter drum than the dynos used for other results, then the acceleration sweep would go faster. The faster the sweep, the more torque is lost to accelerating the internal engine components, transmission parts, driveshafts, etc, and the less torque makes it to the dyno drum.

Can we get the specs of the dyno that Jesse's Girl was run on, then maybe Wes can provide some insight on how that dyno compares to the dyno that Prodigy uses?

Pickles, what do you say to dynoing your rig to give a stage 1 number?

I'm still in debt to the household savings account (and will be for months), so I don't think I'll be going on a dyno. NOLA will be giving us both a stage 1 and stage 2 dyno chart, so he's at least giving us a valid comparison between 2 things. If I ran on a dyno, I would just have stage 1 results with nothing to compare to.

BTW, NOLA, make sure you get the raw dyno run files from your dyno operator (they should be able to email the files to you). Those files are MUCH more useful than a printout of the dyno chart!