4.3 V-6 conversion

[81laredo]

I am in California and need to meet the smog requirements here. I was thinking of doing a AMC 258 i6 / 4.2l engine swap or just that Fuel Injection and Head. After discussing this with the Smog Referee (yep there is one!) these could get complicated and I am not sure how easily they will pass smog.

I am wondering about a 4.3 Vortec conversion. Anyone have any experience with it or can lead me in the right direction?
thanks in advance.

 

[Coach]

I am in California and need to meet the smog requirements here. I was thinking of doing a AMC 258 i6 / 4.2l engine swap or just that Fuel Injection and Head. After discussing this with the Smog Referee (yep there is one!) these could get complicated and I am not sure how easily they will pass smog.

I am wondering about a 4.3 Vortec conversion. Anyone have any experience with it or can lead me in the right direction?
thanks in advance.

I was looking into the same thing, but now I'm looking at an LM7 4L60e swap instead. The cost would be about the same and the gas mileage wouldn't be very different. The LM7's a easy to find and there are a lot more aftermarket parts for them since they are compatible with most LS1 accessories.

Just something to think about. I haven't started my swap yet, but that is where I will be starting soon.

 

[Sasquach]

Here is the way I see it. The fact that the engine will or will not pass the emissions test is not the concern but is your conversion smog legal?
The AMC 258 i6 / 4.2l motor with the Ca. Mopar kit or the Ca. throttle body kit is approved and will pass if your engine is sound.
All other engine swaps need to be complete transplant from the donor including all orig. electronics then it will need to be approved by the referee and who knows then.
Is not OK to transplant just the fuel injection system or seperate parts from one engine to another.
You can research this and what is CARB approved by executive order on there website.
I spent much time on this prior to me upgrade and it boils down to how much $ you want to spend or how much time you want spend trying to get approval. For me it narrowed down to one choice and it turned out to be a good one.

 

[81laredo]

Here is the deal. I did discuss this with a smog referee and some engines do pass easily while others have inherent problems and the AMC 258 i6 / 4.2l is one of them. Using the 4.0 head and FI may help but California is making the Smog Requirements much more stringent and should get even harder with prop 23 passing. I would hate to make a swap and have problems in a couple of years. A buddy of mine is going through just that with the MOPAP Fuel Injection on a AMC 258 i6 / 4.2l (rebuilt engine AMC 258 i6 / 4.2l Head and with a complete MOPAR kit).
I have a '96 Tahoe with the 350 and it has 225,000 miles on it and still passes smog easily. I just bought an '06 Pontiac G6 and that little V-6 is amazing with almost 200 HP. I haven't ruled out using this Engine/Transmission just yet but would rather try to sell it (I have put almost 100K on it myself).
The 4.3 Vortec may fit my needs but I was looking for advice on this. Looks like the Bell Housing is about $400.00 and another $100.00-AMC 150 .00 for the Motor Mount Kit depending on which one is used.

 

[Sasquach]

Something is wrong with that picture? my AMC 258 i6 / 4.2l when stock passed smog with flying colors but made you dizzy and left you with burning eyes and a headache while driving, now with the Mopar system you can detect zero emmisions short of putting you face in the tailpipe.

 

[Sasquach]

By the way, did they say if they would approve the 4.3 motor?

 

[81laredo]

The standards are changing and getting more difficult now that 23 has passed. There is no "Grandfathering" from what I have been able to research. My AMC 258 i6 / 4.2l is stock and came out a "gross polluter" when tested.
I was on track to do a 4.0 Head with Fuel Injection swap (I have the Fuel Injection, Computer, Distributor and Sensors).
As far as the 4.3 it is a later engine and should meet the newer standards easier. I am no expert but would rather make one change and be done with it.

 

[IOPort51]

The last time I had the AMC 258 i6 / 4.2l emissions tested was in the middle 90's and it passed with numbers substantially better than a large percentage of new cars were capable of.

 

[Mattduran]

Not sure about your emissions side of it but I had a AMC 258 i6 / 4.2l in a 73 CJ5 a few years back. Really liked the motor. Used to V-8's so was skeptical at 1st. It was really decent on power! Was running 36" swampers on it to. I imagine the vortec motor would be an excellent choice. Good luck!

 

[81laredo]

I like the AMC 258 i6 / 4.2l but it does present a couple of problems when it comes to smog. All of those vacuum lines, smog pump and any other piece of smog needs to be in place unless there is a FI up-grade
The Mopar system is about $2,500 and the Howell is about $1,500 for the CARB approved system. I was considering using junkyard parts but that could get close to the cost of simply buying a system and then there is the smog policw to deal with.
I still haven't made up my mind but the chevy V6 is right near the top, after all the Dauntless Buick 225 V6 was a great choice not all that long ago.

 

[Cheepjeep85]

isn't the howell tbi kit carb approved? its $1200 and seems fairly simple to do. plus the head swap i don't see why you couldn't pass any emissions test since it is carb approved. then again i know nothing about california emissions, or any for that fact.

 

[81laredo]

You're right and I was considering the Howell Kit until I talked to them. What they told me was that some of the Vacuum Lines and the Smog Pump stayed in place with their system. If I go through this exercise I want to get rid of all of that smog from the 80's.
PS My buddy with the Hesco kit passed smog the other day. Hesco directed him to make the necessary changes and he got the cert. This shows well for them and their product support!

 

[BrockGrimes]

The 4.3l is a common swap talk to Novak adapters.
Drop them an email and ask question they helped alot when I did the swap on a yj.
Also check with More for your motor mounts.
I was in ca by the way!

 

[Ron Ferrando]

Re: m38A1/CJ5

Buy an older jeep and one does not have to meet the SMOG requirements. I put a CJ5 on a M38A1 frame and did not have to smog the vehicle It is licensed as a 1954. I put a Chevy 4.3 V6 Vortec in my ride. (See the pics at Ron Ferrando Member Gallery) I have been working on this ride for five years. SM 465 tranny, WARN Overdrive , DANA 18, Detroit lockers front and rear, 5.38 gears, 11 inch brakes, Boxed frame, 9 inches of lift. Take a look at my new project, the restoration of a CJ2a . The 1950 Jeep pickup bed with the Willys Overland logo is the trailer I am building for my CJ. Once one gets bit by the JEEP bug it just seems to get worse. The CJ2a will take several years to finish. I am building it completely stock. The Chev 4.3 V6 is the best. Mine is bored 30 over, high compression pistons, roller rockers, headers, edelbrock cam, intake and carb. Tons of power and with the Overdrive I can cruise at 55 MPH at 2500 RPM's with 538 gears. The Overdrive makes it happen on and off the road. I can split every gear giving me 24 forward and six reverse gears. The V6 is much lighter and stock at 262 cubic inches thats almost as much as the chevy 265 and 283 v8's. I love mine wouldn't trade it for anything. thought about putting one in my CJ2a but I want to keep it original!!! Keep in touch RON

 

[81laredo]

that would be all well and good but if I ran across a cop that knows the difference between a CJ5 and a CJ7 then .....
I want to do this right and legal. We will be towing the CJ7 behind our motorhome. A few extra $$$ in the beginning will pay off over time. I am still considering the AMC 258 i6 / 4.2l upgrades as another option though.

 

[twcj8]

Wow, all I can say is I'm REAL glad I live in Texas. My head hurts after
reading about an engine swap. The only ref. I need to worry about is the one I've been married to for 39 years.

 

[81laredo]

39 years.......same woman.........no need to swap!!!!!!!!!!!!!