4.3 vs I6?????

[wedgeseven]

I recently purchased a 1989 Jeep Wrangler with a 2.5L (manual)......I purchased with the intent of swaping engines....my question is what are the advantages of a 4.3L chevy vs. the Jeep I6(4.2 or 4.0), Heres the whole situation....I already have a 4.3(non vortec) with transmission(automatic), that is in my old blazer but would need to be rebuilt....2nd part of my question is which one would be the cheaper route....rebuild the 4.3 or buy a new jeep I6 and transmission, as well as how much trouble would it be to switch the jeep from current manual to an automatic with the 4.3.......hope this makes sense



thanks

 

[Junkpile]

OT: bike paint job

Does the transmission need to be rebuilt too, or just the 4.3? If the transmission is good, a 350 V8 should bolt to it. It should be a 700R4, so it is a great transmission. If it is in a S series Blazer I think it would already have an NP231 Tcase mounted to it, right?

 

[wedgeseven]

The transmission is working but its questionable, I would have it rebuilt....as far as the transfer case and stuff im not really sure.....all this is sitting in my 1991 s10 blazer I would have to do some checking into that. So your suggesting beef it up more and drop a 350 onto that transmission insted of using the 4.3 or gettin an I6??? Im new to this whole process obviously=P


Thanks

 

[Snitty]

switching to the automatic would actually be easier than keeping it all manual... if the 4.3 needs rebuilt, then toss it and get a 350... they are all over the place, but it is now race season and harder to come by... as Mr Pile said, the 700r4 is a good transmission, and should be what is mated to a 4.3... we just put one of those trannies in an 87 monte carlo... i'd suggest getting the heavy duty shift kit for it... its like 30 bucks and well worth it

 

[Bounty__Hunter]

Should be a NP231C transfer case, similar to what you have now.

I recommend using the 4.3L over the 4.0L, better all around engine and it fits better. It's capable of making more power, there are more performance parts available, and parts for the 4.3L in general are cheaper and more readily available.

You'll just have another run-of-the-mill 4.0L jeep if you go that route, with a worse than factory install.

I recommend the 4.3L over doing the 350, especially since you already have it. I've done a YJ 350 swap before, and would do the 4.3L if I do it again.

 

[Snitty]

is it a throttle body injected 4.3?

 

[wedgeseven]

it is the non vortec so its carbourated(I believe that is the case with non vortec anyway).....and adding another question on top of the hold....as far as going 350 to 4.3 same transmission and TC right??? and then as far as fuel pump...gears and all that other good stuff what else has to be done as far as mods when swapping....haven't got a chance to find anyone around here that is knowledgeable about this sort of thing.....thanks a ton for all your help so far.

 

[Junkpile]

As long as you are going to have to rebuild it, why bother with the 4.3 when the same setup will accommodate a mild 350 that you wouldn't have to run as hard?


I'm not going to bother going into it, but for the record.....I would rather have the Jeep I6 than the Chevy V6. Since you already have the 4.3, that changes things a little in your case though.