Go Back   Jeep Garage - Jeep Forum > Jeep Platform Discussion > Grand Cherokee - WJ > Engine Performance/Intake/Exhaust

Join Jeep Garage Today
Reply
 
Thread Tools Display Modes
 
  #1  
Old 10-23-2010, 09:42 AM
Member
My Jeep: 2000 4.7L WJ
 
Join Date: Oct 2010
Posts: 12
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 1445
emtclark is on a distinguished road
3" exhaust on 4.7 too much?

Looking to install Kolak's 3" cat-back exhaust on my 4.7 WJ. I live in Colorado at 6,100 ft altitude. Unfortunately, my local exhaust guru advises against that large an exhaust because of low-end torque loss due to altitude.

I put the same exhaust on my '93 5.2 ZJ with no problems; worked flawlessly, same location (Colorado, 6,100 ft).

Do I need to open up the intake (cold air intake) to offset the (possible) torque loss?

Thanks
__________________

__________________
Reply With Quote
  #2  
Old 10-23-2010, 10:13 AM
Long Live the Graphite Ghost

 
Join Date: May 2009
Posts: 13,418
Thanks: 55
Thanked 132 Times in 114 Posts
Rep Power: 542631
robpp has disabled reputation
Re: 3" exhaust on 4.7 too much?

yes. open up the intake to compensate. maybe consider a small port on the tb for increased flow as well.
__________________

__________________
Reply With Quote
  #3  
Old 10-23-2010, 10:29 AM
Member
My Jeep: 2000 4.7L WJ
 
Join Date: Oct 2010
Posts: 12
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 1445
emtclark is on a distinguished road
Re: 3" exhaust on 4.7 too much?

Thanks. What's been the best selling/performing CAI for the 4.7? I'd like to consider doing a home brew intake VS spending $200-300 on a kit.

Suggestions?
__________________
Reply With Quote
  #4  
Old 10-23-2010, 11:28 AM
Scottina06's Avatar
JeepGarage Founder
My Jeep: 2014 6.4L SRT8 WK2
 
Join Date: May 2009
Location: Berea, Kentucky
Posts: 49,229
Thanks: 866
Thanked 972 Times in 687 Posts
Rep Power: 7717861
Scottina06 has a reputation beyond reputeScottina06 has a reputation beyond reputeScottina06 has a reputation beyond reputeScottina06 has a reputation beyond reputeScottina06 has a reputation beyond reputeScottina06 has a reputation beyond reputeScottina06 has a reputation beyond reputeScottina06 has a reputation beyond reputeScottina06 has a reputation beyond reputeScottina06 has a reputation beyond reputeScottina06 has a reputation beyond repute
Garage
Re: 3" exhaust on 4.7 too much?

also look into the HO cams...big performance jump
__________________
SCOTT
The HARDER you work...the LUCKIER you are!
2014 REDLINE red Jeep SRT "BLOODIED\BlackOps CFR Edition" 1 of 1
2013 JKU Wrangler 10A-stormtrooper'ed, JW Speaker and more!
Previous JEEP rides-
2013 Jeep Grand Cherokee SRT-deep cherry
2006 Jeep Grand Cherokee Laredo-inferno red



Twitter-The_Jeep_Guy
Instagram-thejeep_guy

Reply With Quote
  #5  
Old 10-23-2010, 03:00 PM
FlyinRyan's Avatar
Senior Member
My Jeep: 2002 4.7L WJ
 
Join Date: Jul 2009
Location: Fort Myers, Florida
Posts: 2,802
Thanks: 33
Thanked 31 Times in 30 Posts
Rep Power: 88626
FlyinRyan has a reputation beyond reputeFlyinRyan has a reputation beyond reputeFlyinRyan has a reputation beyond reputeFlyinRyan has a reputation beyond reputeFlyinRyan has a reputation beyond reputeFlyinRyan has a reputation beyond reputeFlyinRyan has a reputation beyond reputeFlyinRyan has a reputation beyond reputeFlyinRyan has a reputation beyond reputeFlyinRyan has a reputation beyond reputeFlyinRyan has a reputation beyond repute
Send a message via AIM to FlyinRyan
Re: 3" exhaust on 4.7 too much?

Quote:
Originally Posted by emtclark View Post
Looking to install Kolak's 3" cat-back exhaust on my 4.7 WJ. I live in Colorado at 6,100 ft altitude. Unfortunately, my local exhaust guru advises against that large an exhaust because of low-end torque loss due to altitude.

I put the same exhaust on my '93 5.2 ZJ with no problems; worked flawlessly, same location (Colorado, 6,100 ft).

Do I need to open up the intake (cold air intake) to offset the (possible) torque loss?

Thanks
Having had both, I would stick with the 3". I had gains across the rpm range. These gains were quantified in my 1/4 mile timeslips- yes, even in my 60' times. Air density changes due to elevation do not have a noteworthy impact on what a motor "likes" or needs.

Opening up the intake is a good idea, the 4.7s need it, regardless of whether you're talking about the intake tube itself, or the TB/manifold.
__________________
Due to my workload, please do not PM me as I do not regularly check my PMs. Thank you :)
Reply With Quote
  #6  
Old 10-23-2010, 03:03 PM
FlyinRyan's Avatar
Senior Member
My Jeep: 2002 4.7L WJ
 
Join Date: Jul 2009
Location: Fort Myers, Florida
Posts: 2,802
Thanks: 33
Thanked 31 Times in 30 Posts
Rep Power: 88626
FlyinRyan has a reputation beyond reputeFlyinRyan has a reputation beyond reputeFlyinRyan has a reputation beyond reputeFlyinRyan has a reputation beyond reputeFlyinRyan has a reputation beyond reputeFlyinRyan has a reputation beyond reputeFlyinRyan has a reputation beyond reputeFlyinRyan has a reputation beyond reputeFlyinRyan has a reputation beyond reputeFlyinRyan has a reputation beyond reputeFlyinRyan has a reputation beyond repute
Send a message via AIM to FlyinRyan
Re: 3" exhaust on 4.7 too much?

Quote:
Originally Posted by emtclark View Post
Thanks. What's been the best selling/performing CAI for the 4.7? I'd like to consider doing a home brew intake VS spending $200-300 on a kit.

Suggestions?
Alot of people go with a K&N FIPK, but I personally opted to homebrew one myself. I used 4" aluminum piping, DEI Cool tape, and sillicone couplers.
__________________
Due to my workload, please do not PM me as I do not regularly check my PMs. Thank you :)
Reply With Quote
  #7  
Old 10-23-2010, 10:43 PM
Member
My Jeep: 2000 4.7L WJ
 
Join Date: Oct 2010
Posts: 12
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 1445
emtclark is on a distinguished road
Re: 3" exhaust on 4.7 too much?

Quote:
Originally Posted by FlyinRyan View Post
Alot of people go with a K&N FIPK, but I personally opted to homebrew one myself. I used 4" aluminum piping, DEI Cool tape, and sillicone couplers.
Thanks Ryan, do you have a picture of your home brew intake?
__________________
Reply With Quote
  #8  
Old 10-23-2010, 10:48 PM
Member
My Jeep: 2000 4.7L WJ
 
Join Date: Oct 2010
Posts: 12
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 1445
emtclark is on a distinguished road
Re: 3" exhaust on 4.7 too much?

Thanks for the replies guys. That helps and once I have it on I'll look into both the CAI and the F&B throttle body to open up the intake more. What about the Superchips programer? I looked into previous threads about an "order" to the mods for the 4.7 but one never was suggested...
__________________
Reply With Quote
  #9  
Old 10-23-2010, 11:08 PM
Scottina06's Avatar
JeepGarage Founder
My Jeep: 2014 6.4L SRT8 WK2
 
Join Date: May 2009
Location: Berea, Kentucky
Posts: 49,229
Thanks: 866
Thanked 972 Times in 687 Posts
Rep Power: 7717861
Scottina06 has a reputation beyond reputeScottina06 has a reputation beyond reputeScottina06 has a reputation beyond reputeScottina06 has a reputation beyond reputeScottina06 has a reputation beyond reputeScottina06 has a reputation beyond reputeScottina06 has a reputation beyond reputeScottina06 has a reputation beyond reputeScottina06 has a reputation beyond reputeScottina06 has a reputation beyond reputeScottina06 has a reputation beyond repute
Garage
Re: 3" exhaust on 4.7 too much?

the superchips or an SCT tuner is def. a mod needed for the 4.7
__________________
SCOTT
The HARDER you work...the LUCKIER you are!
2014 REDLINE red Jeep SRT "BLOODIED\BlackOps CFR Edition" 1 of 1
2013 JKU Wrangler 10A-stormtrooper'ed, JW Speaker and more!
Previous JEEP rides-
2013 Jeep Grand Cherokee SRT-deep cherry
2006 Jeep Grand Cherokee Laredo-inferno red



Twitter-The_Jeep_Guy
Instagram-thejeep_guy

Reply With Quote
  #10  
Old 10-24-2010, 12:12 AM
Unholyskorn86's Avatar
Member
My Jeep: 2005 5.7L WK
 
Join Date: Sep 2009
Location: Bristol, CT
Posts: 566
Thanks: 0
Thanked 1 Time in 1 Post
Rep Power: 2381
Unholyskorn86 is on a distinguished road
Send a message via AIM to Unholyskorn86
Re: 3" exhaust on 4.7 too much?

I got one for my 4.0, and if it is anything like the 4.7.....it is well worth it just for the fact that my acceleration was just spot on....from a 2 second delay. That and the mileage across the board for me (note this might not be for every case) was increased slightly.

Oh yeah, good luck bro let us know how ya do.
__________________
WANT TO MAKE MONEY? http://tinyurl.com/lolbusup
Then PM me for more info!
Reply With Quote
  #11  
Old 10-24-2010, 02:48 PM
Member
My Jeep: 1999 4.7L WJ
 
Join Date: Apr 2010
Posts: 51
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 1668
ilirdino is on a distinguished road
Re: 3" exhaust on 4.7 too much?

I'm definitely thinking 3" pipes for my WJ but I don't have the elevation issue to grapple with. I love the exhaust note with a Flowmaster 50 and a K&N 77 and I can only imagine the gloriousness with 3" pipes.

What is the general consensus regarding the F&B TB?
__________________
'99 Jeep Grand Cherokee Limited (4.7V8)
*K&N 77, Akebonos, and Flowmaster 50
**Addco Rear Sway, chrome grill, V3 Projectors, and HID lows next on the agenda
Reply With Quote
  #12  
Old 10-25-2010, 02:37 AM
FlyinRyan's Avatar
Senior Member
My Jeep: 2002 4.7L WJ
 
Join Date: Jul 2009
Location: Fort Myers, Florida
Posts: 2,802
Thanks: 33
Thanked 31 Times in 30 Posts
Rep Power: 88626
FlyinRyan has a reputation beyond reputeFlyinRyan has a reputation beyond reputeFlyinRyan has a reputation beyond reputeFlyinRyan has a reputation beyond reputeFlyinRyan has a reputation beyond reputeFlyinRyan has a reputation beyond reputeFlyinRyan has a reputation beyond reputeFlyinRyan has a reputation beyond reputeFlyinRyan has a reputation beyond reputeFlyinRyan has a reputation beyond reputeFlyinRyan has a reputation beyond repute
Send a message via AIM to FlyinRyan
Re: 3" exhaust on 4.7 too much?

Quote:
Originally Posted by ilirdino View Post
I'm definitely thinking 3" pipes for my WJ but I don't have the elevation issue to grapple with. I love the exhaust note with a Flowmaster 50 and a K&N 77 and I can only imagine the gloriousness with 3" pipes.

What is the general consensus regarding the F&B TB?
The F&B is a piece of artwork....it is the absolute best of the best.When you have the resources to make a new TB casting from scratch, its only natural that it's going to be better than any stock casting based unit out there.
__________________

__________________
Due to my workload, please do not PM me as I do not regularly check my PMs. Thank you :)
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
Lambo "Look" Exhaust on SRT? Chaoul1 Grand Cherokee - WK 33 10-12-2013 08:45 AM
5" exhaust tips mandan007 Visual Modifications 29 10-12-2013 03:35 AM
"Fake SRT8 Exhaust, opinions? TimmyB Visual Modifications 44 08-23-2009 08:53 PM

Powered by vBadvanced CMPS v3.2.3

All times are GMT -5. The time now is 11:51 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Copyright 2012 - JeepGarage.Org
The Jeep Grand Cherokee Owners Community