Engine swap info

[The_Commodore]

OK, so I need a new engine in my 91 Explorer. I found a 4.0 SOHC asking $850. The guy says its like new. I heared the SOHC is a good option for a new engine. Do I have to install any kind of conversion kit and if I do, how much does it cost? Really, I have no experience with this and any info on the subject is good.

 

[BrooklynBay]

Some things are different on the later model SOHC engines, such as the sensors, PCM (also known as the computer), wiring harness, and transmission.

 

[ExploderHOKIE]

check wiring harnesses, thats gonna be the big thing, but also check on mounting and other hardware

 

[MrShorty]

PUtting an SOHC into a 1st gen. I'm pretty sure it can be done. However, at the very least, you've got to get the computer that goes with it. Your '91 computer is designed for the OHV, which is a different animal with different engine management needs. Of course, the computer that comes with the SOHC is going to be looking for a 5R55E transmission. I don't know if the PCM could be reprogrammed or not to control the A4LD. If not, then you'll also be finding a transmission to put in it.

In short, I think swapping to an SOHC could open quite a can of worms. I don't know all the specifics. The same question was asked at TRS recently, and the consensus there was that it's doable, but probably not worth the effort.

 

[410Fortune]

wrong Mr Shorty, the SOHC can run with the OHV computer

http://www.explorerforum.com/forums/showthread.php?t=159001

SOHC is a great option for your 91 IF you have a 5 speed or want to run a C4/5 automatic

THIS IS NOT A SIMPLE BOLT IN AFFAIR and you had better know what you are doing.

 

[MrShorty]

Learn something everyday. Certainly not "plug and play" simple, but doable.

 

[410Fortune]

DO ABLE and becoming quite popular! Especially in the So Cal desert scene

I went V8 instead

 

[CDW6212R]

The clearance at the AC box is an issue, the V8 fits easily. Good luck,

 

[The_Commodore]

The clearance at the AC box is an issue, the V8 fits easily. Good luck,

What about that? Can you just drop that in and bolt it on?

 

[CDW6212R]

Many have done the 302 swap, there is limitless information here to help. The SOHC engine is taller/wider in the area of the AC box.

I have a 99 SOHC that I rebuilt. I originally wanted to drop my 93 body onto it, until the AC box issue. Since then I have heard that a corner can be cut out and flipped/epoxied back in. I understand that, but I don't know how much of the box has to be cut away.

The 302 and 4R70W trans is easier to find and work on then the SOHC. I chose the SOHC for its potential fuel mileage. I'm a mail carrier, to me 10mpg is typical on route. If I get 11 or 12mpg I'll be thrilled, so far I have 240 miles on my 99. Good luck,

 

[The_Commodore]

What if I just wanted to put in another 4.0 V6? Would I still have to take off the transmission and t-case, or would it be just as easy to leave them in and just take the engine?

 

[410Fortune]

re read this post, that was just answered

 

[The_Commodore]

re read this post, that was just answered

But either not clearly enough for me to understand or I am becoming retarded.

 

[410Fortune]

You can put a SOHC V6 in your 91 using your 91 computer, but the transmission will explode behind the new power AND if its an automatic this is not a good idea (not sure the 91 computer will control the A4LD automatic with the new SOHC engine, and even if it did your 91 auto cannot take the power)

So the OHV to SOHC conversion is great for people who have a 5 speed or decide to use another non computer controlled automatic (C4/5 or 700r4, etc)

So when you get to this point you are looking at similar monies and time to a v8 drivetrain conversion (not engine swap) so the SOHC becomes not worth it when you could have a V8

Hope that helps

 

[The_Commodore]

Oh, I see. Now that I reread the post, I see that I was the one who was not clear. I was asking if I could put in another standard issue 4.0 V6 OHV engine without having to mess with the drivetrain or take it out or anything. I'm just trying to get my truck running as quickly, easily, and cheaply as possible.

I think maybe I am becoming retarded...

 

[410Fortune]

Oh I see!!

Sure you can! You can get a good used mileage OHV 4.0L from a 91-2001 Ranger or Explorer for $300-700 at junk yards with a warranty

the basic block did not change from 91-2001 so any will work, but you will have to use your 91 exhaust, intakes as well as accessories and sensors.

Here is a thread where I put a 97 engine into a 95 truck:
http://www.explorerforum.com/forums/showthread.php?t=151705&highlight=97+95

91-92 are the weakest of the 4.0L's, prone to head cracking
93-94 got better heads
95+ is the best option, even more internal upgrades.

 

[410Fortune]

Fyi to do this you dont buy a SOHC 4.0L, OHV only
The OHV was 89-2001 (ranger and explorer)
the SOHC is 97+ Explorer so when looking at 97-2001 engines make sure you are looking at the OHV, both are 4.0L V6

 

[The_Commodore]

Thanks man! That was just what I was looking for and I think I will try to do that. Now I just need to lay my hands on an engine hoist...

 

[410Fortune]

My 1.5 ton hoist was $85 floor model from Checker, so shop around!

 

[BrooklynBay]

Check Harbor Freight, and WWW.Eppys.Com.