I have a quick question. I have a blazer and have ad one for a couple years. It is getting up there in mileage and has already had some leaks (that have been fixed) but i am curious as to what year 4.3's will be a direct swap into mine. It is a 96 v6 with 4-wheel drive. Any ideas what year 4.3's will be a quick drop in swap for mine so that when i blow this thing i can go to a yard and get a lower mileage 4.3 to swap in?


Any help would be great!!!

 

Welcome to the site.
Your best options will be '96 and newer. Swap your old intake and sensors over the new engine.
The problem with a '95 or eariler is the intake and fuel systems. The intake to head bolt angle changed. When your at the junk yard, take a look at the angle of the bolts that connect the intake to the heads. Make sure the donor engine matches yours, if not you may be swapping heads too.

 

Thanks for the welcome. I would not go any older than 96, i am just wondering how new i can go without having an electrical nightmare. I know with past cars of mine, that even when they look the same sometimes they change to like an electronic transmission or use different sensor shapes, etc. I guess what i am asking is what year motors could i swap into my blazer that would be identical, no wiring hassle, same mounts, use the same control module, etc...

 

Any mid-96+ (so long as it has the plastic upper intake plenum) will work as a direct replacement for your 4.3L. Sensor differences (if they exist) may require you to reuse your sensors, but all mounting provisions and sensor locations should be identical for any 96+.

One thing you may want to do is remove the SCFI injection spider and replace all of the o-rings inside before dropping it back in (cost $28). At this time you may also want to soak the poppet injectors in some carbon cleaner to forego any problems with them. If you have some extra money, you can purchase a newer MFI injection spider ($280?) that does away with the poppet valves and moves the injectors down to the port instead of up in the injector pack.

 

Thanks for the info. when this motor finally dies (hopefully not for a while) i will definately be asking questions here. It is just about to roll 200,000 so it should last a little while but it has had its problems so we will see. Thanks again for the info!!!