Prodigy Performance 3.6 Turbo DIY Install

[UselessPickles]

Here's an awesome (long and informative) article about how intercoolers work, and how the decision of when to use intercooler water spray most effectively/efficiently is more complicated than most people assume. Their solution is an "intelligent" water spray controller monitors ambient temperature, intercooler core temperature, and fuel injector duty cycle to spray the intercooler when it needs it, and conserve water when it isn't needed.

http://www.autospeed.com/cms/article.html?&A=0527

[AGOM]

Pickles, this is what I have been trying to explain for sometime, I had this problem before the tune and after the tune it's still there but not as before.
The jerkiness, boost coming in and out with no change in pedal input, I even tried driving with manual shifting, but still the same.
If I go for a quick acceleration it will pick up quick and then have that pause and continues on, it's as if Its not comfortable with small pedal inputs, it wants you to floor it all the time.
But it's weird that you got it after the tune!

[UselessPickles]

I finally had my first encounter with another performance vehicle out on the road

I'm at a red light, in the right of two lanes. The right lane ends about 1/4 mile after the intersection. There's a car beside me, and a modern Dodge Challenger behind me. Light turns green, and I accelerate normally, but faster than the car beside me, because I want to make sure I'm ahead enough to merge out of my lane before it ends without being a dick and cutting this other car off.

I notice that the Challenger is staying very close to my rear bumper, probably waiting for enough gap between me and the car that was next to me so he can change lanes and pass me. I shift into 2nd at a fairly normal RPM because I'm not showing off at this point.

Then I see the Challenger make his move. I see an aggressive lane change and hear the Hemi start to roar a bit. No time to downshift at this point, so I just step on the throttle in 2nd, but I'm not quite up to the RPM where full boost kicks in. The driver of the Challenger must have noticed I suddenly started accelerating more, because I then heard the Hemi transition to full roar, and the Challenger lunged forward.

Right as the Challenger gets beside me, I transition to full boost. Couldn't have timed it more perfectly if I tried. Next thing I know, I'm several car lengths ahead of the Challenger, can still hear the Hemi roaring, but he's still falling back. I also notice at this point that I'm now going faster than I would prefer, and my lane is going to end soon, so I merged over and let off the gas to coast down to to more appropriate speed.

The Challenger quickly catches up to me just as the right lane ends, and rides my rear bumper for a few seconds. Then he aggressively passes me at full throttle, flips me the bird, and speeds excessively up to the next red light. I had not cut him off, blocked him from changing lanes, or anything else rude. His rude gesture can only be the result of being a sore loser.

I thought that was the end of it, but I was wrong. It turns out that "sore loser" is an understatement for this guy...

He stops at the red light way ahead of me, but I can see he keeps inching forward, trying to get a jump on the green light. As I approach, he just takes off, running the red light before it was even close to changing (cross street still had a green light).

There's another red light just about 1/8 mile ahead with two lanes now. This time he actually comes to a complete stop, but at a slight diagonal,partially occupying both lanes. I guess he really didn't want me to pull up beside him.

I was actually going to be turning right at that intersection anyway, so I slowly/carefully squeezed past him, stopped, checked to make sure traffic was clear, and proceeded with my turn (right turn on red is legal here). The driver of the Challenger sat still, hands on the wheel, facing straight forward the whole time.

I hope he's still trying to figure out wtf happened. I wonder if he could hear the turbo, or just watched me quietly pull away with my stock exhaust.


Unfortunately, I forgot to check for badging to see if it was an R/T or SRT. I did some simple math based on dyno results I have found for Challengers and the difference in curb weight between them and my Jeep (Challenger is 400 lbs heavier than my Jeep!), along with Prodigy's recent 380 whp claim, to determine how the power:weight ratio compares.

Newer 6.4 SRT: Nearly identical power:weight ratio (I have 3% advantage). This car was definitely not a 6.4 SRT, unless he never really went full throttle near the beginning, or else it would have initially blown past me, then I would have just barely maintained the gap between us as I transitioned to full boost.

Older 6.1 SRT: Actually has nearly identical peak hp/tq numbers at the wheels, but due to weight difference, I have an 11% advantage in power:weight. This might be a possibility. He was definitely quickly gaining on me before my boost kicked in. An 11% advantage would definitely allow me to keep increasing the lead as long as I was in the upper RPM range, but I'm not sure if an 11% advantage is enough to let me increase the lead as quickly as I did. Really hard to tell.

5.7 R/T: I have a 30% advantage in power:weight! That could make sense too. It seems like that big of an advantage would have put me further ahead more quickly, but I could be wrong.


Wish I would have looked for the badge. Oh well. It was thoroughly entertaining and made me smile for the rest of the day.

[gbaumann]

So to summarize, you smoked the muscle car!!!

[UselessPickles]

Basically. I was more surprised by his reaction. I expected either no reaction, or for him to try to catch my attention at the next light and ask me how the hell that just happened. Not pass me, flip me off, run a red light, then try to prevent me from pulling up next to him at the next light.

I bet it was an R/T and he had already been wishing he could have gotten an SRT. I just rubbed salt in that wound and he couldn't handle it

[gbaumann]

You knocked him out in a fair fight. I suppose you cant be too surprised he didn't get up and ask where you developed your awesome left hook. Most muscle heads will get up and sucker punch you while you're walking away. Yep, it was an R/T.

[UselessPickles]

It finally warmed up enough here to wash all the salt off my Jeep from this winter and add a subtle hint of what lurks under the hood. Have I endangered my sleeper status?

[Timmy]

Have I endangered my sleeper status?

Ba hahahaha... No Pickles, you are still far from endangering your sleeper your status.

[UselessPickles]

ProCharger says: "comes standard with the industry’s largest and most effective air-to-air intercooler for the Jeep Wrangler JK. "





Prodigy says: "that's cute"





UPDATE: Procharger seems to have updated their website to no longer claim to have the largest intercooler

[UselessPickles]

I got curious and stopped at a local landscape supply to weigh my Jeep on their scale:



3960 lbs

This is with a full tank of gas (just filled up 2 miles away) and whatever random stuff I typically have in the Jeep at all times (nothing really heavy: hat, sunglasses, tow strap, gloves, soft top boot, etc).

According to this document from Jeep, the curb weight of the base model 2-door is 3849 lbs: https://www.jeep.com/assets/pdf/wrangler_specs.pdf

Mine is the base model + A/C. I haven't been able to find anything about how much weight is added by A/C.
I also can't find any details on how Jeep measures curb weight. Some manufacturers measure with a full tank of gas, 3/4 full or 1/2 full.
So since I didn't weigh it before installing the turbo, there's no way to determine how much weight is added by the stage 2 turbo kit.

But now that I do know my actual weight, and Prodigy has released some dyno charts, I have all the info I need to simulate how quickly my Jeep should be able to accelerate.

Assumptions for the simulation: Total vehicle weight is 3960 lbs + 140 lbs (my weight) = 4100 lbs. Launch at 2500 RPM (seems reasonable to avoid roasting the clutch). Each gear change completed in 0.6s (the best I've seen in a data log).

Max acceleration: ~1.1 G around 27 mph in 1st gear

0-60 mph: 4.85s
1/8 mile: 8.63s @ 88.28 mph
1/4 mile: 13.22s @ 106.56 mph


NOTE: The 1/8 mile trap speed of 88 mph is not only enough to travel through time, but is also about the same as the stock 1/4 mile trap speed, which takes about 15.5-16.0s, depending on which car website's results you trust.

Now if you're willing to roast the clutch a bit (or install a high performance clutch) for some 4000 RPM launches...

0-60 mph: 3.99s
1/8 mile: 7.94s @ 88.89 mph
1/4 mile: 12.51s @ 106.87 mph


And how about some highway/freeway "passing power" examples...

60-80 mph, 6th gear: 26.90s
60-80 mph, 5th gear: 13.81s
60-80 mph, 4th gear: 5.66s
60-80 mph, 3rd gear: 2.51s

40-60 mph, 6th gear: 15.64s
40-60 mph, 5th gear: 12.00s
40-60 mph, 4th gear: 8.23s
40-60 mph, 3rd gear: 3.60s
40-60 mph, 2nd gear: 1.56s


Obviously, with the turbo's big gains in the mid-to-upper RPM range, downshifting is your friend here. It's interesting that 5th and 6th gear are faster from 40-60 than 60-80, even though they are at lower RPMs in the 40-60 acceleration, with less torque available. That's a good example of how much more power is lost to aerodynamic drag above 60 mph.

I think I'll try data logging some 40-60 and 60-80 accelerations in different gears to compare real world results to the simulated results and get an idea of how good my predictions are. I have no way of reliably simulating turbo spool/lag when initially going full throttle, so real-world results should be slower if I start my acceleration right at 40/60 mph. If I start the acceleration at a lower speed, the time it takes for me to pass through 40-60 and 60-80 should be close to the predicted results.