AMC v8 into a CJ7

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   i have a spare 390.. etc. im looking to put into my daily driver jeep that is currently a 3spd auto and I6... i have a t-5 as well but i dont think either of them can hold up to the 390... what kind of modification are necessary to do that? exhaust, suspension, motor mounts? and driveshaft length differences between the auto and man?? thanks.

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68AMCAMX :) Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Oct/27/2009 Location: Newtown CT. Status: Offline Points: 30	Post Options Post Reply Quote 68AMCAMX :) Report Post Thanks(0) Quote Reply Topic: AMC v8 into a CJ7 Posted: Nov/01/2009 at 5:01pm
	i have a spare 390.. etc. im looking to put into my daily driver jeep that is currently a 3spd auto and I6... i have a t-5 as well but i dont think either of them can hold up to the 390... what kind of modification are necessary to do that? exhaust, suspension, motor mounts? and driveshaft length differences between the auto and man?? thanks.
	68 AMX 390 4 spd, 65 Rambler American 440 Convertible 290 auto, 85 Jeep CJ7 rebel machine 390 5 speed.

FuzzFace2 Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jul/05/2007 Location: Angier, N.C. Status: Offline Points: 10356	Post Options Post Reply Quote FuzzFace2 Report Post Thanks(0) Quote Reply Posted: Nov/01/2009 at 9:37pm
	Is the T5 hooked to a transfer case? If not then I would not look at this route. You got peddle setup to use a stick? I can tell you the frame brackets are different between 6 & 8 and some one does make them Just cant remember who right now. What auto trany you have now? You could bolt the 8 to the auto and not have to mess with any thing else. Now what to worry about?? The auto trany & transfer case, front & rear axles & drive shafts not holding up to the power of the 390. Now if you have a transfer on the T5 you can measure where the drive shafts are from the front of trany face or bell housing and see if different from the auto. May want to ask over on Bulltear.com site they are into AMC power & 4x4’s or jeepforum.com BTW there is a Youtube video of a 360 think CJ7 with a T5 that is a runner. BTW#2 there is someone running a T5 behind a 390 in a machine, doesn’t drag race but said he drives it hard. Dave ----
	TSM = Technical Service Manual 75 Gremlin X v8 for sale 70 Javelin 360/auto drag car 70 Javelin 360/T5 Street car

tufcj Members Profile Send Private Message Find Members Posts Add to Buddy List Supporter of TheAMCForum Supporter of TheAMCForum Joined: Jul/10/2007 Location: Watkins, CO Status: Offline Points: 4086	Post Options Post Reply Quote tufcj Report Post Thanks(0) Quote Reply Posted: Nov/04/2009 at 8:54pm
	Your CJ would have a TH400 1976-1979, or a TF727 or TF998(?) 1980-up. Either would hold up to a mild V-8. The 390 crank would have to be machined to fit the auto, or a no-machine adapter fitted (someone sells them). The flex plate could be balanced to match the 390. The V-8 will bolt up to the auto trans, same bolt pattern. The motor mounts would need to be changed to CJ specific V-8 mounts, or aftermarket mounts like the ones from M.O.R.E. Fuel pump is on the opposite side, some re-wiring, new exhaust, and a bigger radiator if the I-6 has a 2 core. The Jeep T-5 would be marginal behind a V-8. Might get expensive to adapt a t-case if it's a Ford T-5. I'd go find a junkyard 360 from a Wagoneer w/auto if you really want a V-8. Bob tufcj Edited by tufcj - Nov/04/2009 at 8:55pm
	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

jeepdirtboy Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Fan Joined: Dec/02/2009 Location: st peters, mo Status: Offline Points: 9	Post Options Post Reply Quote jeepdirtboy Report Post Thanks(0) Quote Reply Posted: Dec/02/2009 at 12:26am
	304, 360, or 401 will fit with mods, but I dont think the 390 will without machining crank

jeepjerry Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Nut Joined: Dec/11/2008 Location: SE Wisconsin Status: Offline Points: 291	Post Options Post Reply Quote jeepjerry Report Post Thanks(0) Quote Reply Posted: Dec/11/2009 at 7:23pm
	I went from a 258 to a 360 in my 76 cj-5. The motor mounts on the v-8 are wider than the 6 cyl. I left the stock 6 cyl brackets on my frame and dropped the 360 in to check it out. The motor mounts have one bigger stud towards the engine and two smaller studs toward the frame. When i dropped it in, only the two lower studs on the motor mounts matched up with the holes for the upper studs on the frame brackets. Simple fix.....take some 1.5" angle iron, drill a hole in it for the upper stud, and weld or bolt it to the frame mount. My motor doesnt sit too high either, i have a 5" tall air cleaner atop my offy dual port with plenty of room under the hood. My t-case is also dropped 1.5" which raises the front of the engine up.
	-72 SST Javelin -under restoration. Alfano Performance 360. -76 CJ-5,strong 360, 6" lift, 35"s. -77 J-20, 4bbl 360/t-18, 33"s. marlinsteve's son

rockrash Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Dec/23/2009 Location: Georgia Status: Offline Points: 34	Post Options Post Reply Quote rockrash Report Post Thanks(0) Quote Reply Posted: Dec/27/2009 at 8:28am
	The passenger side frame mount from a V-8 Cj is what is needed for the swap. The drivers side 6 cyl. mount can remain. Not a difficult swap. Stick with stock manifolds on the exhaust. There are some in the frame headers for the CJ's but they limit access to the starter etc. as well as clutch linkage. A Jeep T-5 will not hold up for long behind a V-8. Hell, they weren't very reliable behind a 6 cyl. Either the Dana 20 or Dana 300 T-case is plenty strong. If you have a T-5 then you are running the Dana-300 already. The Ford NP-435 transmission will work with the Dana-300 with an adapter from Advanced adapters, and no drive shaft changes would be needed from the T-5/Dana 300 combo. It has a 6.69:1 first gear in it and is incredibly strong. Usually it is driven like a 3 speed with a granny low first. I use this set up in my 73 Commando Bullnose. Hope this helps.