Since my JK is a daily driver as well as the workhorse of the house I am looking at keeping it fairly stock as far as suspension and tire size goes (keep MPG up and expense down). However from the decent number of people who have gotten the RIPP charger and given it very good reviews on this site, it just got me thinking about a question or two that may help a lot of us using our JKs for daily use where MPG and dependability are paramount.

I was wondering at what RPM the RIPP tune for the SC begins to change the fuel map compared to the stock map. I wonder this because when I drive around town, to keep fuel economy up on my 6-speed I will many times keep the engine RPM just over idle. As a result one of the things I have worried about by adding ANY supercharger is that the fuel map would either remain the same as stock at these low RPM (800 - 1000) and the small change in air delivery from the SC could cause it to run lean and/or rough and being more prone to stall out at these low RPM. OR the tune from the SC would richen the mixture up way too much at these low RPM and, once again, cause it to run rich (killing mpg) and/or rough making stalling out easier. As someone who bought his JK to drive slow and enjoy having the top down and not tearing up the pavement this is one of the big things that has stopped me from getting any supercharger up to this point: I just want to make sure at least some attention and testing was given to sub 1000 RPM operation.

Also when I am on the highway I can get great fuel economy (~23 mpg average highway) by leaving the JK in 6th and maintaining 70 mph. But since my engine RPMs at 70 are only ~2000 (3.21 gears with 32" tires) I have also been wondering whether the RIPP charger would allow me to maintain nearly stock mpg by leaving it in 6th on the highway (due to not much change in the fuel map below where the SC starts to really hit) but to also have more power up top so if I need passing power I throw it down into 4th and have 180 HP rather than 120 HP at my disposal.

Anyway I know that is a long and detailed post, but I would just love to hear feedback from RIPP. I am unfortunately in the position of being the engineer that knows way too much about engines and the very fine lines that exist in tuning and power delivery, so I just want to make sure if I get something to boost power for passing power during highway driving, the power delivery while driving in the city (with my low RPM driving style) won't suffer.

 

I am not a techie by any stretch of the imagination, but with a SC and pulling a trailer, the hills on route 80 between Bloomsburg and Clearfield are easy to manage. Passing is no longer an adventure.

 

Have you seen much difference in fuel economy before and after the SC on the same route? I make regular trips to and from north Pittsburgh via I-80 so I am definitely interested in your real-world experience. It's a pretty easy drive until you have an elephant race going up some of those hills in front of me with a bunch of impatient drivers flying up behind me. Those are the times when I think of how nice it would be to have 50% more power

 

my real world mileage is 15mpg....I do alot of highway driving. The SC wont be a hemi, but it makes a differerence. I am adding the headers next year. FYI, I have Gen 1 Ripp.

I've had the SC for a year now, have about 25kl miles on it. No problems. I cant remember what the mileage was pre-SC. Remember, once you get it, you tend to race everything at redlights...Vette's, Milk Trucks, Hummers, and Saturns.

The whistle coming down the road sounds cool, though I am probably going to get their addon for the Blow out Valve, its supposed to make it quieter.

Good Luck with your decision.

 

Yes - This is a long and detailed question - !

The short answer is the entire RPM band is tuned - 0-8000rpm (an over rev protection for 6spd guys). We replace the OEM MAP sensor with a RIPP designed unit which has a very broad slope. The MAP sensor reads the vacuum to boost transition and everything in between. And thats where we got fanatical about it. We want a RIPP supercharged JK to feel like a V8, not only deliver the power in low to mid RPM, but also to drive like a larger displacement engine. Considering the amount of clients that use our system to rock crawl, throttle control at slight RPM's was critical. Additionally end users have the ability to fine tune your throttle sensitivity in the diablo itself.... there are a host of end user defined adjustment you can change to cater our tune to your style of driving. However the out of the box tune has had a near 100% success rate (with a few rouge CEL's here and there we take care of in emails)

Lastly - the condition in which your driving is called closed loop (where all four O2 sensors are trimming fuel). You should know we are at a .2 correction (which is fantastic for an aftermarket tune). Meaning the ECU only has to correct .2% of our mapping -/+.... this is about as close to OEM a bottled tune can get. If this isn't enough, you can follow Jkerrs (an active JKF poster and RIPP client) route and have a custom tune done with a reputable diablo tuner (a situation only Jkerr has done). Consequentially & Understandably he found our tune to be spot on, but conservative...

Its not rocket science - its an air pump - wait is a rocket and air pump??

Questions always welcome
RIPPTECH

 

Excellent info thank you for that - if we had to suggest your next investment we would suggest the GEN2 Electronics and Front Mounted Intercooler - they will overall be a better upgrade than adding the headers (unless your manifolds are cracked). The GEN2 will open lots of power down low and give you much more drivability. Its hard to describe in a post the difference - but its substantial, enough for us to suggest it over our killer header program.

RIPPTECH

 

Thank you so much for your responses, that sounds great! I guess the one thing I would be curious to know is about how much power gain can I expect at 2000 RPM with the new gen 2 kits in the 6-speed? I just ask because with the 3.21 gears and 32" tires, that is about where my engine RPMs sit on the highway in 6th gear and I am curious to know whether I would have a little extra torque at that low of engine speed or not. I guess are the torque (and thus power) curves any different for the gen 2 compared to the gen 1 in a 6-speed? If so is there any way you could post them or point me to a post where the torque and power curves are for the gen 2s?

Thanks again guys!

 

bump, any difference in the torque / power curve between the gen 1 and gen 2 for a 6-speed?

 

Naturally with the added air volume there will be more throttle response right from idle and therefore power. Torque is generated by rotating mass at 1000 rpm there's not much rotating mass. This engine's response is closer to 2000 than 1000. Driving it that low is driving it outside its natural operating point. The blower with deliver much more air to the engine than it would normally be able to suck in on its own. We take advantage of that and push time up a bit and lean it out. This makes it much more responsive and fun to drive, the experience is like driving na larger engine. We will have our 6spd numbers posted soon, we have a 2010 we are almost done with.

RIPPTECH

 

Sounds great! I can't wait to see!