If You Were To Build A V8 Comanche, Which Version Would Work Best?

[H3RESQ]

Yup, that old AMC would be cool factor till you hit a hill out in the woods and it starts cutting out. It wouldn't be worth a propane swap or efi conversion. Oh and it will get about 12 mpg.

5.0, well maybe a brand new one, otherwise you still get maybe 16mpg. Also while there is aftermarket for the 5.0 it is not equal to a LS and specifically when it comes to putting it in a XJ/MJ.

The LS is the one I see being easiest, most cost effective, has the best aftermarket support specific to this swap, and even with lift and tires (geared properly) you can expect over 20mpg out of the 5.3!

The diesel, well good mpg, horrible niose, etc,etc. AND how bout the fact of the weight on your front end. I think people need to stop with the 4bt and man up and do a 3.0 CRD swap out of a Grand..or Benz. NOW THAT WOULD BE COOL!!!!

[JeepcoMJ]

Yup, that old AMC would be cool factor till you hit a hill out in the woods and it starts cutting out. It wouldn't be worth a propane swap or efi conversion. Oh and it will get about 12 mpg.5.0, well maybe a brand new one, otherwise you still get maybe 16mpg. Also while there is aftermarket for the 5.0 it is not equal to a LS and specifically when it comes to putting it in a XJ/MJ.The LS is the one I see being easiest, most cost effective, has the best aftermarket support specific to this swap, and even with lift and tires (geared properly) you can expect over 20mpg out of the 5.3!The diesel, well good mpg, horrible niose, etc,etc. AND how bout the fact of the weight on your front end. I think people need to stop with the 4bt and man up and do a 3.0 CRD swap out of a Grand..or Benz. NOW THAT WOULD BE COOL!!!!

You are not correct on most of this.

 

An AMC 360 can get 20mpg in a fullsize j-truck with quadra-track. All it takes is a torquer cam and a PROPERLY tuned carb. Yes it can/will cut out on inclines, but that's ALL carb'd motors, even those with special floats to avoid that issue.

 

I have done it. If you look at simple laws of physics, with that being possible, power to weight states VERY simply that you WILL increase mpg with that motor in a lighter vehicle.

 

I have a buddy with a 360 in his javelin and j-truck getting 19mpg when he's light on the throttle. And that is the key point here. ANY motor will get crap mileage when you peg the gas pedal all the time.

 

My crown vic got 19mpg with a 5.0 in it. I drove it light.

 

I have friends with 350s in CJs YJs TJs XJs and all manner of non-jeep related vehicles that get more than 17mpg as well.

 

 

A v8 swap means you CAN get bad gas mileage, directly correlating to the way you drive. That has an equal and opposite reaction if it's driven nicely.

 

I got 24mpg regularly out of my 99 XJ with a 4.6 stroker, new model intake, borla header, neon srt4 injectors, torquer cam (dropping hp/torque curve to 1750rpm) 62mmTB and ax15 with nv242 tcase left in full time. The new owner (Jakeman) hasn't managed higher than 22-23 on highway.

 

My KJ is rated at 14mpg city, 17-18 highway. I get 16mpg mixed and 21-22 highway with it by driving it nice.

[JeepcoMJ]

 

Ok I have a question. Why a ls1 ? My line of thinking would be old school no computer no major electrical problems. Something like a chevy 327 or 283

 

 

LOL....... clearly you haven't read this entire thread. 

 

Emissions.  It'll be required to have an evap canister, cat converter(s), possibly an EGR valve...... that kinda thing.  If the original truck had it, the modified version has to have it as well.

 

Secondly, carbureators are the suck.  Especially out here where elevation changes are common just driving across the state.

 

The diesel engine really turns me off in such a small truck.  The noise in particular.  Those 4BT Cummins engins sound like a friggin' farm tractor and while torque monsters, move the truck like a turtle for daily driving.  No thanks.

 

A nice, powerful fuel injected V8 with an overdrive transmission........ :thumbsup:

My buick 3800 swap is an EGR and emissions delete. charcoal canister still present, NoX catalytic converter, missing post cat o2 sensor. 96 motor in 86 chassis. Passed state visual inspection in that form, as the new motor more than surpasses the emissions of the 86 model year 2.8l, and passed sniffer tests with better than 96 expectations.

 

The only real worry with an engine swap is that it is not legal in most states to install a motor from an older model year than the vehicle.

[yxmj]

Go with the Stroker....In the long run it will be easier on the pocket book.....and (depending on who built it) will give you all the power and reliability you will ever need.  . :MJ 1: .