Print Page | Close Window

J10 headers? For 3in exhaust?

Printed From: TheAMCForum.com
Category: Competition
Forum Name: Jeeps and Eagle 4x4 fun.
Forum Description: Rock crawling events or results, Muddin' it through the riverbed with your Eagle
URL: https://theamcforum.com/forum/forum_posts.asp?TID=105575
Printed Date: Apr/19/2024 at 1:44pm
Software Version: Web Wiz Forums 12.03 - http://www.webwizforums.com


Topic: J10 headers? For 3in exhaust?
Posted By: amc401t10
Subject: J10 headers? For 3in exhaust?
Date Posted: May/09/2020 at 10:43am
I crashed my hot rod, gremlin x, 550 hp 401. Putting the 401 in my 82 j10.
Gotta have 3in exhaust! My long tube headmans exit so close to frame and Tranny, 
I don't think they can fab 3in to attach? Was thinking shorty headers might work?
Anyone got 3in, or even 2.5 in duals from headers?
My current 360 exits through 2in. Dumps in front of rear wheels.
Help?



-------------
1-owner 74 gremlin x 401, t10,3.73 12 bolt,750carb,reed 250@50 cam, roller rockers,msd,offy int.
72 amc matador 401 727
84 j10 ,360, 727
1970 4-door rebel sleeper(455 pontiac,turbo 400)
79 spirit,4.2



Replies:
Posted By: BrotherBamc
Date Posted: May/09/2020 at 12:25pm
You shouldn't have any problems with a 3 inch exhaust on your J-10. I think it all depends on the skill level of your exhaust guy.
I just had 2 1/2" pipe from collector all the way back in my Gremlin. We did have to cut part of the bolt on collector off to get the 2 1/2" pipe to hook up, but my exhaust guy did it.





-------------
77 CJ5 360
73 Gremlin 401 4 speed
2006 Dodge Magnum R/T AWD
http://www.lxforums.com/board/garage.php?do=user_garage_view&id=19745" rel="nofollow - My Garage


Posted By: amc401t10
Date Posted: May/10/2020 at 11:01am
I went from 2.5in to 3 in on my gremlin, couldn't get over rear end, so turned down in 
front of rear.felt like another 100 HP above 4000 rpm! But damn it was loud!
On the j10 the collector exits right by the frame rail and crossmember . Theirs wires and fuel and brake
Lines in their. The 2in fits with only limited clearence on each side.
I thought maybe with the shorty header I could go under the crossmember? 
Ps what powers that gremlin?


-------------
1-owner 74 gremlin x 401, t10,3.73 12 bolt,750carb,reed 250@50 cam, roller rockers,msd,offy int.
72 amc matador 401 727
84 j10 ,360, 727
1970 4-door rebel sleeper(455 pontiac,turbo 400)
79 spirit,4.2


Posted By: BrotherBamc
Date Posted: May/10/2020 at 11:20am
I consider it a mildly built 401.
.30 over, comp 280ish cam, speedpro 27 dished forged pistons, moly rings, 750 double pump Holley, stock 993 heads, Mallory unilite, MSD 6al ignition box, Comp cam roller rockers, hooker super comp headers, RobbMc mechanical fuel pump and an old school, carb cooking, torker intake with a 1 inch spacer..



-------------
77 CJ5 360
73 Gremlin 401 4 speed
2006 Dodge Magnum R/T AWD
http://www.lxforums.com/board/garage.php?do=user_garage_view&id=19745" rel="nofollow - My Garage


Posted By: BrotherBamc
Date Posted: May/10/2020 at 11:24am
Exhaust note at an idle..

https://1drv.ms/v/s!AosAPjtbCPrhjjNucVtZZfzWh4t8" rel="nofollow - https://1drv.ms/v/s!AosAPjtbCPrhjjNucVtZZfzWh4t8

-------------
77 CJ5 360
73 Gremlin 401 4 speed
2006 Dodge Magnum R/T AWD
http://www.lxforums.com/board/garage.php?do=user_garage_view&id=19745" rel="nofollow - My Garage


Posted By: amc401t10
Date Posted: May/12/2020 at 11:24am
Makes me miss mine, it was my 1st car, 74 X with 304. 
10 years later it was a 401, T10, 3.73 12 bolt. 500 HP
It was a hand full! Only AMC in my area that got respect.
I'd run anything! Got beat a few times.
But surprised a Whole lot of other brands!
The good old days!


-------------
1-owner 74 gremlin x 401, t10,3.73 12 bolt,750carb,reed 250@50 cam, roller rockers,msd,offy int.
72 amc matador 401 727
84 j10 ,360, 727
1970 4-door rebel sleeper(455 pontiac,turbo 400)
79 spirit,4.2


Posted By: fastjeep
Date Posted: May/28/2020 at 11:07pm
Have a 86 J10 with the shorty headers ,i made a 2.5 Y pipe to right side. Used a Flowmaster 2.5 to 3 merge pipe then ran 3 from there. With flowmaster muffler it sounds good. We in PA there always threating to go after modified exhaust ( all the coal burners and their stacks ) this looks like stock pipe. I know since put on Fitech injection it really sounds good. Used the early left side header with rear exit and with 4" lift no clearence problems with drivers drop pumpkin.  


Posted By: Jmerican
Date Posted: May/30/2020 at 12:57am
The exact parts fastjeep is describing make for an excellent FSJ 360  exhaust, with all mandrel bent pieces of course. The collector is a key piece. 


Posted By: amc401t10
Date Posted: Jun/07/2020 at 12:51pm
Fastjeep,  got any pics. 
I've benn looking under mine, (I need the long tube(ceramic coated) headers to take advantage of the 500hp), I'm thinking 2.5 to mufflers then 3 out? Their might be room for 2.5 above the crossmember, 1 down ea side, if I move my wires,   if not room, I'll run the Dr side over and down the pass side .  Pilenty of room on pass side.
 Again , I drove this engine in my car with 2.5, turbo mufflers, and thought it was awesome!  Then went to 3in, with flowmasters, felt like another 100hp, above 3500 rpm!
Thanks for all the ideas!


-------------
1-owner 74 gremlin x 401, t10,3.73 12 bolt,750carb,reed 250@50 cam, roller rockers,msd,offy int.
72 amc matador 401 727
84 j10 ,360, 727
1970 4-door rebel sleeper(455 pontiac,turbo 400)
79 spirit,4.2


Posted By: Heavy 488
Date Posted: Jun/07/2020 at 2:41pm
Felt like another 100 horse or at least sounded like it? LOL


Posted By: fastjeep
Date Posted: Jun/09/2020 at 8:35pm
I will see if I can get some pictures to post.


Posted By: amc401t10
Date Posted: Jun/18/2020 at 10:33am
[QUOTE=Heavy 488]Felt like another 100 horse or at least sounded like it? LOL [/QUOTE

No it was more than sound, picked up .5second in 1/8th.]


-------------
1-owner 74 gremlin x 401, t10,3.73 12 bolt,750carb,reed 250@50 cam, roller rockers,msd,offy int.
72 amc matador 401 727
84 j10 ,360, 727
1970 4-door rebel sleeper(455 pontiac,turbo 400)
79 spirit,4.2


Posted By: RobinPDX
Date Posted: Dec/20/2020 at 9:37pm

thx


-------------
Rob Wiley


Posted By: tufcj
Date Posted: Dec/20/2020 at 10:07pm
You need 30 points (posts) to be able to post pics, unless you use a hosting service.  Keep posting, you have 21.

Bob
tufcj


-------------
69 AMX
74 Javelin AMX
67 Rogue

If you need a tool and don't buy it...
you'll eventually pay for it...
and not have it.
Henry Ford


Posted By: RobinPDX
Date Posted: Dec/20/2020 at 11:16pm
Ahh, thx.



Print Page | Close Window

Forum Software by Web Wiz Forums® version 12.03 - http://www.webwizforums.com
Copyright ©2001-2019 Web Wiz Ltd. - https://www.webwiz.net