jeep4power
New member
My question is a Fuel MPI Injection conversion on a present 4.2l 258 CID or 4.0l I6 replacement, which is better and why? For vehicles such as the Jeep YJ, "88".
Fuel MPI Injection conversion or 4.0l I6 replacement...
- Thread starter jeep4power
- Start date
redrooster
New member
A lot of people like the propane. I wouldn't run it just because the bottle takes up too much space and the availability is not as good as gas.
There are many options so let's start where most on this board are going to say anyway: put a Motorcraft 2100 carb on it and be done with it. Okay, now that's out of the way so we can move on.
Both are great engines, so you can hardly go wrong. I don't like aftermarket EFI systems because they are pricey, not as complete as OEM systems and are sometimes hard to come by replacement parts should you need them.
With that said, "I" still wouldn't put a 4.0 in it. I don't know what a used 4.0 runs, but EFI Chevy motors can be had for $700 all day long around here.
There are many options so let's start where most on this board are going to say anyway: put a Motorcraft 2100 carb on it and be done with it. Okay, now that's out of the way so we can move on.
Both are great engines, so you can hardly go wrong. I don't like aftermarket EFI systems because they are pricey, not as complete as OEM systems and are sometimes hard to come by replacement parts should you need them.
With that said, "I" still wouldn't put a 4.0 in it. I don't know what a used 4.0 runs, but EFI Chevy motors can be had for $700 all day long around here.
SenorCole86
New member
I know I'm not really answering your question, but do yuo have both engines in your possession? If so, I think a 4.6 L stroker is a candidate AND he obvious choice.
jeep4power
New member
I know I'm not really answering your question, but do yuo have both engines in your possession? If so, I think a 4.6 L stroker is a candidate AND he obvious choice.[/QUOTE]
No I do not have both engines, and money is not an issue for my YJ. So I will research the 4.6 L STROKER. I am new to the Jeep world and this forum site too. My Yj has been sitting for over a year outside an insurance salvage yard before I bought it at a steal with minor vody damage to the rea bumper and tail-gate, and I am planning to start with my engine. I often hear that I should replace my Carter carb to Fuel injection, and now I am hearing to change to a Motorcraft 2150 carb, "one carb builder in my area say's it will blow away most throttle body injection setups on both performance and power, and to keep the 4.2 block and upgrade the head to a 4.0 head and the Distributor to an HEI or DUI for more power and performance as well. What do the rest of you think about this?
If the 4.6 STROKER benefits more, then so be it. My goal is to use my Jeep both as a daily commuter and off-road. It seems that when I go off-road it drives better than it does on-road. MPG may or may not be an issue to me.
No I do not have both engines, and money is not an issue for my YJ. So I will research the 4.6 L STROKER. I am new to the Jeep world and this forum site too. My Yj has been sitting for over a year outside an insurance salvage yard before I bought it at a steal with minor vody damage to the rea bumper and tail-gate, and I am planning to start with my engine. I often hear that I should replace my Carter carb to Fuel injection, and now I am hearing to change to a Motorcraft 2150 carb, "one carb builder in my area say's it will blow away most throttle body injection setups on both performance and power, and to keep the 4.2 block and upgrade the head to a 4.0 head and the Distributor to an HEI or DUI for more power and performance as well. What do the rest of you think about this?
If the 4.6 STROKER benefits more, then so be it. My goal is to use my Jeep both as a daily commuter and off-road. It seems that when I go off-road it drives better than it does on-road. MPG may or may not be an issue to me.
Last edited:
Bounty__Hunter
Super Moderator
You don't have to go all-out with the stroker unless the engine needs a rebuild, otherwise run the 2150 as it'll give good performance at angles similar to FI. The 4.0L head is a good upgrade but not a bolt-on, there's a few small easy mods that need to be done but the HP will make it worth it.
jeep4power
New member
GREAT I will start with the "2150"! But I do hav 1 concern, one person told me that Motorcraft Carb's r no good, whats true in that? Yet he dont own a Jeep, but a GM high performance/off-road Truck?!?! Wich leaves me to believe that he dont know Jeeps!
SenorCole86
New member
Yeah, sounds like it. The motorcraft carb is an excellent upgrade for your Jeep. I'm running one and have nothing but good things to say about it. Good luck bud.
redrooster
New member
The Motorcaft is a good carb, but I can't fathom one out performing TBI in any aspect except price. With that said, port injection far outperforms TBI. That's why I threw the chevy option in there. They have put the 4.8, 5.3 and 6.0 in nearly every truck out there and the salvage prices are way down.
For my own interest as well as yours, maybe SenorCole and Bounty will chime in with dollar and horsepower figures on various Jeep engine mods they have done. I think this will be interesting and help you decide.
Here's the ballpark cost on what it would take to install a '99 and up Chevy Vortec:
Engine: $700 and up depending on mileage
Wiring harness: get the factory one and have it and the ECM modified for $425
Transmission adapter: $500 +/-
Motor mounts: $130 (Advance Adapters, I made my own)
Electric fan: $150
K&N filter instead of clunky air box: $50
So give or take $2000 to install a 5.3. It's probably not the cheapest way to go, but you get a lot for the money. With the ECM tuned, my engine puts out roughly 315 hp. I had way more than that in my fuel injected AMC 360 and the 5.3 runs far better and consumes alot less fuel for sure.
For my own interest as well as yours, maybe SenorCole and Bounty will chime in with dollar and horsepower figures on various Jeep engine mods they have done. I think this will be interesting and help you decide.
Here's the ballpark cost on what it would take to install a '99 and up Chevy Vortec:
Engine: $700 and up depending on mileage
Wiring harness: get the factory one and have it and the ECM modified for $425
Transmission adapter: $500 +/-
Motor mounts: $130 (Advance Adapters, I made my own)
Electric fan: $150
K&N filter instead of clunky air box: $50
So give or take $2000 to install a 5.3. It's probably not the cheapest way to go, but you get a lot for the money. With the ECM tuned, my engine puts out roughly 315 hp. I had way more than that in my fuel injected AMC 360 and the 5.3 runs far better and consumes alot less fuel for sure.
Similar threads
