454 in the FREE Scrambler

Well many questions so here goes, 1st I have all the components (for the most part) to do a 454,th400,205,d-60 frt,d-80 rear to put in a 84 Scrambeler yet people are screaning you fool it wont work. I say hog wash! I have 7 Jeeps and all but one are V8 conversions but Ive never done the big block yet. I know I will have exhaust issues, I will buy the Novak coated shorty headers but I cannot find any info on how the will route from there. Also I have an extra YJ frame lying around to put the body on if that would be a better deal, my head is spinning so could some one point me in a educated direction to someone that has done this swap or the frame swap?  

If your objective is to put in a bunch of parts because you have them, well, you'll probably learn a lot.

But, if your building something for a specific purpose, what are those objectives, so we can help you meet them?  

I picked this set up well for many reasons, Ive done the SB chevy swap like a million others, I have the resources here in Fairbanks, Alaska to use just about any set up I choose and this one I like yet cant find anyone who has done it for me to ask a few questions. My biggest concerns are exhaust route and frame strength, thus the question of swapping to a YJ frame. My wife and I will be moving to the central U.S when we retire and this will be the rig I want to build to take cross country to as many events as I can. (on a trailer) I am mostly into heavy/difficult trails, hillclimb feak, not a big mud guy.I would like to try a bit of rock crawling also. This will be a frame up job. I have a real good idea of what I want but always want input from other minds. I grew up attending the Minnesota Go-four wheelers Memorial weekend event in Dresser, Wisconsin. Im a bit of the old school wheeler and think you can build a home school rig that will hold its own to a 100K Atlas this, Dynatrac/Currie that, over priced rig. JMO. All input is welcomed, Thanks!!  

Here's where I think you'll have issues.

Small frontal exposure for the radiator making cooling difficult. The 454 is hard to cool in the best of situations. CJ frames are weak for sure. Steering linkage and header clearances. TH400/205 is a long setup further complicated by a long snout on the Dana 80. This will make for a short drivesahft. Depending on how much suspension you have, you may end up with extreme u-joint angles. Consider placing the rear suspension as far back as possible, maybe also including a frame extenson.  

Yeah, I think I'd swap in and lengthen the YJ frame. The CJ frames are just garbage, even in a stock application.

Exhaust routing will be very tight. You might consider outside the framerails.

A 454 will fit. It's been done. But you will need to use the largest radiator you can fit behind the grille.  

Like these guys pointed out it looks like cooling and length are going to be the biggest hurdles. It also sounds like you are pretty mechanically inclined, so I would do what the good editor recommended to get this set up to work, lengthen the YJ frame. Once you've done that there should be plenty of room for everything and you'll have quite the runner...

Keep us posted on this project!  
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So it's not a Jeep... sue me... it's still faster!

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Very good advice. I failed to mention that I was planning on stretching the frame and moving the body perches as needed etc. to get my length. I have downloaded the blueprints to do the math, just was wondering if you guys have ever seen this type of frame swap done. Now I do have a custom alum. radiator that supports a SB 400 now and was planning on using it along with a pusher fan set up, do you think that will work?  

A fan mounted in front of the radiator and no engine driven fan?

The only way to keep it cool is goning to be a propperly shrouded engine driven, heavy duty clutch, 19" fan.  

You don't need an engine driven fan.  Motorcraft part RF-123 is an 18" 2-speed electric fan with built in shroud that will cover the entire radiator.  I pulls 4500 CFM on high, starts up at 100amps, then settles to about 40amps steady.  Get a good alternator.  It's for 93-96 Lincoln Mark 8s.  There's als the RF-64 that runs a bit more RPMs on high speed.  Both parts look identical, only the fan motor speeds and costs are different.  I use one, it blows like no other fan I've ever seen.  

Drvn:

As for the frame swap, I don't know how much you looked at the drawings online, but they suck horribly.  If you look at them (at least the ones I found) with the intent of building a frame, you'll see there are many many dimensions missing.  I'm thinking of the YJ frame stretch too, and that's what I've discovered.

As far as the 454... I've seen Jeeps with them.  Its doable.  In Alaska, I doubt you'd have many overheating issues, but out here, the guys I've found wished they'd put a small block in it.  

Sure the later small blocks are more money, but big block parts aren't cheap either.  I'd give a good look at the LS-series small blocks.  
- Pete Trasborg, Associate Editor, JP Magazine

Hey guys.. I dont know much about the scrambler but i have a 95 yj and i swapped in a 396 which is the same as a 454. It has a Novak aluminum radiator which you can get from griffin or many other radiator shops and the novak motor mounts for the big block.. you have to run an electric fan and you might need to move the grill forward about 2 inches to meet the edge of the hood.. It will look stock and i have never had a cooling problem even with a warn powerplant winch ( which is super tall) mounted up front. I am running it on propane so it does run a little cooler but i am in texas and it still never overheats. The reason i would say run the yj frame is because it is about 38 inches wide at the area you would mount the motor mounts. So the starter, bellhousing  and everything clear. I actually am running full length long tube headers from a 68 chevelle and they fit with no prob. So sorry to drag this out but tech specs as follows---396,turbo350,203-205doubler. it all works, all fits and wouldnt change a thing. Anyways, worry for the novel.. thanks guys..


Josh