The Centrifugal Vs Positive Displacement Decision - Jeep Garage - Jeep Forum

Go Back   Jeep Garage - Jeep Forum > Jeep Platform Discussion > Grand Cherokee SRT - WK2 > WK2 SRT Performance Discussion > Engine Performance/Intakes and Exhausts/Superchargers/Turbos

Join Jeep Garage Today
Reply
 
Thread Tools Display Modes
 
  #1  
Old 10-29-2014, 07:55 AM
Member
My Jeep: 2015 6.4L SRT WK2
 
Join Date: Sep 2014
Location: Melbourne
Posts: 72
Thanks: 12
Thanked 13 Times in 12 Posts
Rep Power: 885
Brashquido is on a distinguished road
The Centrifugal Vs Positive Displacement Decision

Hi All,

I'm looking to get a super charger kit on my MY15 early next year once I have a few thousand kms on the clock. I would describe my requirements as being far more weighted towards drivability and reliability than just having something that is batsh1t crazy to drive. My SRT will be the family car and my daily driver. Essentially the following is what I'm looking for;

  • Sub 4 secs 0~100kph
  • 12 sec 1/4 mile
  • 500+ whp
  • 10l/100km or better for pure highway driving (approx 23.5mpg)
  • Minimal noise (especially in the cabin)
  • Unobtrusive and preferably reversible installation
  • Easy installation to keep installation costs/issues down
  • Reliable parts & operation
  • Forgiving of drivers with little experience of high powered vehicles (i.e. wife)
  • Smooth power delivery rather than something that is going to break my neck
  • Most importantly, minimal risk of busting stock drivetrain
So having read a fair bit but not actually having any practical experience with forced induction, I thought the RIPP supercharger kit based on the Vortech V3 Si Trim centrifugal SC was the best choice for me.

I contacted one of the better known forced induction specialists where I live to get a rough idea on installation costs. I was told the founder of this company who has a Jeep GC SRT himself was going to be installing a positive displacement (I think) Eldlebrock unit. They also went on to say that they moved away from centrifugal SC years ago. I've also read this anti-centrifugal sentiment elsewhere on the net.

Just wanting to know, do I have some sort of newb blinkers on and am missing something about the centrifugal Vs positive displacement SC debate? Would I be correct in thinking the RIPP SC kit is the best off the shelf offering based on my requirements?

Reply With Quote
Sponsored Links
Advertisement
 
  #2  
Old 10-30-2014, 12:32 AM
Member
My Jeep: 2013 6.4L SRT8 WK2
 
Join Date: Jan 2011
Location: Laguna Beach, CA
Posts: 501
Thanks: 22
Thanked 84 Times in 61 Posts
Rep Power: 7828
Carbon6 has a reputation beyond reputeCarbon6 has a reputation beyond reputeCarbon6 has a reputation beyond reputeCarbon6 has a reputation beyond reputeCarbon6 has a reputation beyond reputeCarbon6 has a reputation beyond reputeCarbon6 has a reputation beyond reputeCarbon6 has a reputation beyond reputeCarbon6 has a reputation beyond reputeCarbon6 has a reputation beyond reputeCarbon6 has a reputation beyond repute
Garage
Re: The Centrifugal Vs Positive Displacement Decision

Just reading from above and from the reviews from both here and the red site, the RIPP would be your best bet as far as meeting all the requirements you listed. The other would be Demon's kit, which is also a centrifugal force unit.

From the sound of RIPP's kit, you are getting the most bang for your buck while being the safest to date since (not from experience) the SC is almost completely maxed out. While its not just the SC that can cause damage (people were damaging their motors with diablo's when they first came out for the SRTs) the tune sounds very conservative. Compare dyno sheets on the four SC's available (i.e. Kenne Bell, RIPP, Demon, Magnuson) and think about where your normal driving range is. At 4k RPM you could be looking at up to 200hp difference between each of these SCs.
Reply With Quote
The Following User Says Thank You to Carbon6 For This Useful Post:
  #3  
Old 10-30-2014, 06:13 AM
Member
My Jeep: 2014 6.4L SRT8 WK2
 
Join Date: Nov 2013
Posts: 268
Thanks: 5
Thanked 31 Times in 23 Posts
Rep Power: 1815
jmone has a reputation beyond reputejmone has a reputation beyond reputejmone has a reputation beyond reputejmone has a reputation beyond reputejmone has a reputation beyond reputejmone has a reputation beyond reputejmone has a reputation beyond reputejmone has a reputation beyond reputejmone has a reputation beyond reputejmone has a reputation beyond reputejmone has a reputation beyond repute
Re: The Centrifugal Vs Positive Displacement Decision

I'm a complete newbie to V8's much less SC them, and before I went RIPP I read lots of stuff on the Net and watched a series of YouTube videos on the various design options.

In the end I was convinced by the RIPP setup as I wanted something:
- reliable (also RIPP said if the SC ever failed you can still run the car without the SC)
- quiet (well it is now I've got the new BOV)
- Good Performance increase without breaking stock drive train
- Best price / performance (I'm not after the "most" I could get at the expense of the above)

This is what Vortec says on the differences... though I also figured at the end of the day it did not matter which tech was used without starting to replace other components. At the end of they day you are only going to get a mild boost before stuff starts to break or need upgrading so the other factors I listed were more important.

I've very pleased with my result, and if you are in the region drop by for a test drive.

Thanks
Nathan

Edit - I should say I'm NOT after the fastest truck on the drag strip. I may do this once for fun to see what it can do, but as I'm on public roads it more about responsiveness. Oddly, when my Wife drives the Jeep she now thinks it is now a better drive with the SC on, she thought prior to the SC it was a bit skittish. Don't get me wrong, she is no fan when I drive it! Also, she did not like the noise of the old BOV (my family have nick named it the "Baby Eater" given the screaming noise the BOV made).

It is the best car I have owned.
Reply With Quote
The Following User Says Thank You to jmone For This Useful Post:
  #4  
Old 10-30-2014, 10:16 PM
Member
My Jeep: 2015 6.4L SRT WK2
 
Join Date: Sep 2014
Location: Melbourne
Posts: 72
Thanks: 12
Thanked 13 Times in 12 Posts
Rep Power: 885
Brashquido is on a distinguished road
Re: The Centrifugal Vs Positive Displacement Decision

Thanks for the replies.

I ended up reading comparison articles for an hour or two last night and pretty much reaffirmed the RIPP kit is best for my needs. So hard to find unbiased information, as soon as I sense any sort of fanboi talk in an article for either type of supercharger I more or less discard it. Doesn't appear to leave much reading.

Two cons that keep getting mentioned in regards to centrifugal SC is the noise and the fact power only comes on as the RPM rises where it is constant with positive displacement types.

Unless I am missing something, I don't see the power curve of a centrifugal SC as a downer for this particular application as it would seem logical that this incremental curve would result in a smoother ride and less stress on the stock internals. I've also read that you need to retard the low end ignition map with positive displacement superchargers to prevent detonation, and that modern engines with VVT (such as the Hemi) don't get any particular gains from having this low end boost. This seems to be reflected in the lack of significant difference in 0~100kph times I've seen posted for the Whipple and the RIPP.

The noise factor does concern me a little. I essentially do not want to know it is there during my day to day driving, however I'm not too fussed if I have the right foot stuck into it. Nathan, you mentioned the noise is reduced a lot with the new BOV that RIPP supplied. If it isn't too much trouble, can you post a youtube clip or something with a recording of cabin noise through the rev range? No drama if you can't. I may just take you up on that offer to come and have a drive though. When you are talking dropping circa $13kaud for an upgrade, the cost of a flight to Sydney is probably well worth it.

Apart from these two points of discussion, in terms of operation I only see advantages with the centrifugal SC. Less heat soak, lower discharge temps, saps less power from the engine to run, much easier to install, less parts required, less obtrusive, less weight, better adiabatic efficiency and superior fuel economy under highway driving conditions.

To me, the RIPP kit seems better tailored to the Hemi if you have no intention of replacing any of the stock components. This is exactly the market I am in, so seems the best fit.

Still, will be very interested to see how this Edlebrock twin screw based unit goes as I haven't seen one on a Jeep SRT yet and after the USA->Aus exchange rate, shipping & customs required to get a RIPP unit here they are going to be very much at the same price point installed.
Reply With Quote
  #5  
Old 10-31-2014, 07:07 AM
Member
My Jeep: 2014 6.4L SRT8 WK2
 
Join Date: Nov 2013
Posts: 268
Thanks: 5
Thanked 31 Times in 23 Posts
Rep Power: 1815
jmone has a reputation beyond reputejmone has a reputation beyond reputejmone has a reputation beyond reputejmone has a reputation beyond reputejmone has a reputation beyond reputejmone has a reputation beyond reputejmone has a reputation beyond reputejmone has a reputation beyond reputejmone has a reputation beyond reputejmone has a reputation beyond reputejmone has a reputation beyond repute
Re: The Centrifugal Vs Positive Displacement Decision

Here you go - clip with AC OFF, Radio OFF, in the drive and not moving
- No BOV noise at all comming off WOT
- I really don't notice it at all in normal driving (AC and Radio on, Road Rumble etc)



Thanks
Nathan
Reply With Quote
The Following 2 Users Say Thank You to jmone For This Useful Post:
  #6  
Old 11-02-2014, 03:48 AM
Member
My Jeep: 2015 6.4L SRT WK2
 
Join Date: Sep 2014
Location: Melbourne
Posts: 72
Thanks: 12
Thanked 13 Times in 12 Posts
Rep Power: 885
Brashquido is on a distinguished road
Re: The Centrifugal Vs Positive Displacement Decision

Thanks for that Nathan. No BOV noise and the SC whine isn't that bad either. From that I'd doubt it'd be noticeable on the road. Thanks heaps for posting that.
__________________
White MY15 SRT with HK/Pano/Tow kit. Ordered 26/9/14, Pick up 17/11/14
Current Project: Gathering useful Oz specific info for Jeep SRT owners on OzSRT
Reply With Quote
  #7  
Old 11-02-2014, 05:55 AM
Member
My Jeep: 2014 6.4L SRT8 WK2
 
Join Date: Nov 2013
Posts: 268
Thanks: 5
Thanked 31 Times in 23 Posts
Rep Power: 1815
jmone has a reputation beyond reputejmone has a reputation beyond reputejmone has a reputation beyond reputejmone has a reputation beyond reputejmone has a reputation beyond reputejmone has a reputation beyond reputejmone has a reputation beyond reputejmone has a reputation beyond reputejmone has a reputation beyond reputejmone has a reputation beyond reputejmone has a reputation beyond repute
Re: The Centrifugal Vs Positive Displacement Decision

Your are right, no BOV noise and on road with the AC on, road noise, and the radio at normal levels you don't notice any intrusive noise from the SC.
Reply With Quote
  #8  
Old 11-05-2014, 06:45 AM
Member
 
Join Date: Jun 2014
Posts: 15
Thanks: 8
Thanked 1 Time in 1 Post
Rep Power: 906
peej is on a distinguished road
Re: The Centrifugal Vs Positive Displacement Decision

Quote:
Originally Posted by Brashquido View Post
Hi All,

I'm looking to get a super charger kit on my MY15 early next year once I have a few thousand kms on the clock. I would describe my requirements as being far more weighted towards drivability and reliability than just having something that is batsh1t crazy to drive. My SRT will be the family car and my daily driver. Essentially the following is what I'm looking for;

  • Sub 4 secs 0~100kph
  • 12 sec 1/4 mile
  • 500+ whp
  • 10l/100km or better for pure highway driving (approx 23.5mpg)
  • Minimal noise (especially in the cabin)
  • Unobtrusive and preferably reversible installation
  • Easy installation to keep installation costs/issues down
  • Reliable parts & operation
  • Forgiving of drivers with little experience of high powered vehicles (i.e. wife)
  • Smooth power delivery rather than something that is going to break my neck
  • Most importantly, minimal risk of busting stock drivetrain
So having read a fair bit but not actually having any practical experience with forced induction, I thought the RIPP supercharger kit based on the Vortech V3 Si Trim centrifugal SC was the best choice for me.

I contacted one of the better known forced induction specialists where I live to get a rough idea on installation costs. I was told the founder of this company who has a Jeep GC SRT himself was going to be installing a positive displacement (I think) Eldlebrock unit. They also went on to say that they moved away from centrifugal SC years ago. I've also read this anti-centrifugal sentiment elsewhere on the net.

Just wanting to know, do I have some sort of newb blinkers on and am missing something about the centrifugal Vs positive displacement SC debate? Would I be correct in thinking the RIPP SC kit is the best off the shelf offering based on my requirements?

I too have been looking at the 2 types and although the Ripp system seems the way to go my only concern is the availability of replacement parts in Aust. As I use my Jeep as a daily driver should I smash the front of the Jeep obtaining replacement parts in Melb (Intercooler and pipework) isn't something that is in stock (correct me if I am wrong) and if needing to be shipped in from the USA will just add to the amount of days the car is off the road. Still undecided which way I will go.
Reply With Quote
  #9  
Old 11-05-2014, 08:14 AM
Member
My Jeep: 2015 6.4L SRT WK2
 
Join Date: Sep 2014
Location: Melbourne
Posts: 72
Thanks: 12
Thanked 13 Times in 12 Posts
Rep Power: 885
Brashquido is on a distinguished road
Re: The Centrifugal Vs Positive Displacement Decision

Replacement parts & local knowledge of working with the RIPP kit is a valid point. However, I'm not so sure I would discount the RIPP kit based on if I were to crash my SRT. If you hit something hard enough to bust up your SC intercooler/pipework, then there is going to be major damage to the rest of the car. To my knowledge Jeep don't keep an abundance of stock in Australia anyway so there is likely to be a decent delay anyway. Besides, you can always revert back to stock with the RIPP without a massive amount of trouble.
__________________
White MY15 SRT with HK/Pano/Tow kit. Ordered 26/9/14, Pick up 17/11/14
Current Project: Gathering useful Oz specific info for Jeep SRT owners on OzSRT
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
What are some positive things about the WK2? SUMMITgirl Grand Cherokee - WK2 - 40 09-26-2013 11:09 PM
Decision, Decision BobsWK2 Grand Cherokee SRT - WK2 9 03-04-2013 02:28 PM
There's No Replacement For Displacement :) SMG1 Grand Cherokee - WK2 - 9 03-20-2012 04:32 PM
no positive on relay stealth32 Grand Cherokee - WK 29 02-22-2011 01:57 AM

Powered by vBadvanced CMPS v3.2.3

All times are GMT -5. The time now is 09:00 AM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2016, vBulletin Solutions, Inc.
Copyright 2012 - JeepGarage.Org
The Jeep Grand Cherokee Owners Community

JeepGarage.org is in no way associated with or endorsed by FCA US LLC. Chrysler, Dodge, Jeep, Ram, Mopar and SRT are registered trademarks of FCA US LLC.