4.2L headers vs. manifold - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > General Technical Discussions > Engines & Drivetrain > 4.2L headers vs. manifold

Magnaflow SS Cat Back Exhaust System, Street, High ClearanIntroducing MONSTALINER™ UV Permanent DIY Roll On Bed LineBrand New! Quadratec LED Headlights!

Reply
Unread 10-01-2001, 12:53 PM   #1
CJay7
Registered User
1985 CJ7 
 
Join Date: Oct 2001
Location: IN
Posts: 131
4.2L headers vs. manifold

Has anyone swapped the 4.2L exhaust manifold for a header? What kind of power increase if any was experienced. I have been told that there is no emissions legal header for the 4.2L but so far have not been able to confirm that. If anyone can help it is appreciated.

__________________
'85 CJ-7 - 258 bored .030 w/ mid level cam, 4.0 head, Clifford intake and header, Weber 38, TFI w/ MSD 6, Black Diamond 3" lift, Daystar 1/2" lift shackles, 33x12.5 Goodyear Duratracs with stock 3.31 gears.
CJay7 is offline   Reply With Quote
Unread 10-01-2001, 08:49 PM   #2
osburn
Registered User
1995 YJ Wrangler 
 
Join Date: Nov 2000
Location: Santee, CA U.S.A.
Posts: 1,148
Can't comment on what sort of improvement to expect. But for sure Borla makes an emissions legal header for your engine.
__________________
Matt Osburn
Greengo
Rigrater Score 1032
osburn is offline   Reply With Quote
Unread 10-02-2001, 01:03 PM   #3
Nightclaw
Registered User
1994 YJ Wrangler 
 
Join Date: Jul 2001
Location: Oceanside, CA, USA
Posts: 150
Just to confirm osburn, a buddy of mine was tearing his hair out looking for an emissions-legal header for his '81 CJ. Borla was the only fabricator that had one that would pass smog. He didn't see a lot of improvement, but that's not necessarily a good example as his Jeep ran like crap anyway...
__________________
=========
[b]'94 YJ Sahara Hardtop[/b]
4.0L / AX-15 / Stock NP231 / Stock D30 (open) / D60 (35-spline, Detroit locker, Moser axles) / rear disc brakes / 4.56 gears / Advanced Adapters SYE & CV Shaft / 33" BFG MT-KM's / Thorley Header / Magnaflow Muffler / BesTop Flares
Nightclaw is offline   Reply With Quote
Reply
Thread Tools


Suggested Threads





Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.