Wiring information for Chevy 350 engine swap

[Godzilla]

As many TJ owners, I'm considering an engine and possibly a transmission swap. I know the 4.0 is a dependable engine, but because of our illustrious EPA and their emissions regulations, many Jeep Wrangler owners are having constant issues with O2sensors, catalytic converters, and Evap codes, that many are paying big bucks to rectify. I for one have had enough. Besides the crappy fuel mileage Jeep's are noted for, if I'm gonna be getting bad MPG , it may as well be with a V8 engine. I'm looking into building a Chevy 350 with mild cam, headers, aluminum intake, Holley Carb, and MSD Distributor with 6AL ignition box. No more sensors ! I'm not well versed on wiring however and could use some astute guidance. What wires can I eliminate from the engine, and is it possible to wire the automatic transmission to work without a computer or will I need to swap out to a manual transmission or possibly a TH 350 ? My CJ5 was a simple swap because it originally came with a AMC 304 and 3spd manual transmission. However, with all the sensor for this and sensor for that, I don't want to cut out the wrong wires. So, is anyone out there in TJ land able to assist with information or at least suggest a company that specializes in this type of wiring harness ?
Thanks

 

[Chris]

Are you running carbs or fuel injection?

 

[P man]

Are you 100% sure you want to go back into time 35 plus years?

 

[ColoJeep]

Are you 100% sure you want to go back into time 35 plus years?

Or only go back 34 Years and stick with the 4.0 !

 

[NskLJ]

If you want to do an engine swap and have any type of emission regulations. The motor must be same year or newer. Hemi or Chevy LS swap seem to be the go to. Technically it is a felony to remove or modify emission equipment but I have never seem end users have issues.

 

[Gilaguy23]

Are you 100% sure you want to go back into time 35 plus years?

Personally Id take a carbed 283 or 327 in mine any day. Ive never been DOA with a carbed vehicle,cant say the same for a dead computer controlled turd, Far as fuel mileage...my old 63 GMC PU with a 305 V6 got 20 mpg so whats the big deal with electronic gizmos besides less emissions. Might as well help China and India destroy some air.

 

[P man]

Personally Id take a carbed 283 or 327 in mine any day. Ive never been DOA with a carbed vehicle,cant say the same for a dead computer controlled turd, Far as fuel mileage...my old 63 GMC PU with a 305 V6 got 20 mpg so whats the big deal with electronic gizmos besides less emissions. Might as well help China and India destroy some air.

That's great you have an opinion...I personally wouldn't own something with a carburetor...let me ask you a question...how many times has a modern fuel injected vehicle left you stranded? I know the answer I'm just wondering what you will say. It's easy to spot the old timers that say "they don't build em like they used to" and my reply is thank God I always hated adjusting a carburetor and rebuilding engines at 100K miles.

 

[Pokahpolice]

That's great you have an opinion...I personally wouldn't own something with a carburetor...let me ask you a question...how many times has a modern fuel injected vehicle left you stranded? I know the answer I'm just wondering what you will say. It's easy to spot the old timers that say "they don't build em like they used to" and my reply is thank God I always hated adjusting a carburetor and rebuilding engines at 100K miles.

Wow, someone is real serious about the carb vs fuel injected argument . You need a hug this morning, friend.

 

[Gilaguy23]

That's great you have an opinion...I personally wouldn't own something with a carburetor...let me ask you a question...how many times has a modern fuel injected vehicle left you stranded? I know the answer I'm just wondering what you will say. It's easy to spot the old timers that say "they don't build em like they used to" and my reply is thank God I always hated adjusting a carburetor and rebuilding engines at 100K miles.

4 times so far. The worst was in a newer Ford van headed outta Kingman AZ on a 110 degree day. 2 dogs and the wife were with me. $300 later after a tow to the nearest ford dealer which was in Bullhead IIRC.(sunday) rented a car and went on our way and left the shit box in Bullhead. A few days later we returned on out way home to pick it up. They diagnosed it with a bad 02 sensor. Um sure im thinking. POS crapped out again on the trip back home with the same problem. The second time was in Death Valley in Fall thank fully. Camped at the Kilns up at Wildrose. Cherokee fuel pump died on the way up Gohler wash to check out Mansons cabin. That was a real fun trip...shall I go on?? You right about one thing, they dont build them like the used to, engines last 4 times as long as they did back in those days and yes opinions will vary.

 

[Zorba]

Personally Id take a carbed 283 or 327 in mine any day. Ive never been DOA with a carbed vehicle,cant say the same for a dead computer controlled turd, Far as fuel mileage...my old 63 GMC PU with a 305 V6 got 20 mpg so whats the big deal with electronic gizmos besides less emissions. Might as well help China and India destroy some air.

I'd be MIGHTY tempted to drop a 305 V6 into a Jeep. Best engine in its class EVER made. That lovely low end torque! Coupled with an SM-420 transmission. I grew up with a '63 GMC 1 ton, I'll carry a torch for that truck until my dying day. Everything a truck should be, and NOTHING that it shouldn't.

 

[P man]

Wow, someone is real serious about the carb vs fuel injected argument . You need a hug this morning, friend.

I'm wound pretty tight all the time this isn't a "one off"..rage and anger are what wake me up in the morning...he'll I sprinkle that shit on my Wheaties...in all seriousness though no hugs or carburetors for me

 

[Zorba]

Wow, someone is real serious about the carb vs fuel injected argument . You need a hug this morning, friend.

It isn't so much about carb vs fuel injection - its the over thought complexity of the unreliable computer setup that's the problem. You don't need a computer for fuel injection.

 

[Jezza]

Wiring information? Doesn't the old 350 run with only 1 wire to the distributor? I started one on a pallet once with a jump box and a jumper wire. Not sure if it's worth the effort swaping a 190hp I6 for a 200hp V8 though.

 

[JPHikr]

I would do a 383 with Holley sniper FI mated to a 700r4. Use the Auto meter cluster for dash.

 

[TJPurist]

Painless Performance Products is the way to go. I had an '89 350 Chevy fuel injected truck engine installed in my '89 YJ. Just about all the old engine compartment wiring was ripped out and with the Painless harness it was plug and go. We also replaced the Peugeot transmission with an AX15 . It was a little tricky finding an ECM unit that worked with the 350 and the manual transmission. You don't need to modify the 350. It has all the torque you need ! If I was doing it again however, I would opt for an automatic transmission. Novak Conversions has an excellent web site discussing the many various transplants and supplies the parts to do the job.
That YJ was a real sleeper. The only outward clue that something was different was the big tailpipe outlets and a couple of discrete V8 emblems on the fenders under the word "Jeep". Here in Ontario, I had to apply for official "hot rod" status as the emission stats were different from stock.

 

[5632]

When considering a new motor don't forget about the best motor ever made. An LS.

 

[P man]

When considering a new motor don't forget about the best motor ever made. An LS.

 

[Zorba]

I would do a 383 with Holley sniper FI mated to a 700r4. Use the Auto meter cluster for dash.

The 700R4 transmission was the worst piece of shit ever introduced by GM when it first came out. However, its my understanding that its problems were eventually overcome and it became a reliable unit. Too late for myself and several people I knew - so I still cringe when I hear it mentioned.

 

[5632]

The 700R4 transmission was the worst piece of shit ever introduced by GM when it first came out. However, its my understanding that its problems were eventually overcome and it became a reliable unit. Too late for myself and several people I knew - so I still cringe when I hear it mentioned.

It is now a 4L60E and both are very popular.

 

[JPHikr]

700r4 will not have the wiring as it is just an old style AT with OD.