New guy with engine swap questions 95 in a 97

[ls1bmw]

First I would like to say hello to everyone and thank you all for any information you can provide me. I have searched this forum for hours and have not found any information on the type of engine swap I would like to do. I am assuming it is because to most people it is a step backwards. I would like to swap a 1995 4.0L OHV engine into a 1997 that had a 4.0L SOHC. I know that the engine will bolt up fine I am just wondering if there are going to be any wiring issues. I also can tell that I am going to have to use all the brackets from the OHV engine. The reason I am doing this swap is because I already have both vehicles so the parts are FREE persay. It doesnt necessarily have to be street legal. If it is great if not it becomes a woods car. Once again thank you.

 

[IZwack]

Yes there will be wiring issues but just swap the wiring harness too since you have both vehicles. For example, the SOHC uses a solid state sensor on top fo the driver's side valve cover for the camshaft.

 

[410Fortune]

hmmm tricky! your 97 truck would become a 95 truck, engine computer wise
If its an auto transmission in the 97 then you must retain the 97 computer

Basically, if you want to convert your 97 auto SOHC to a OHV 4.0L (pushrod) you are also going to need a 97 OHV computer, engine wiring harness, sensors and intakes

You can use the 95 OHV block and heads however....

if its a 5 speed truck that changes things

so my questions are:

the 95 truck is an automatic?
the 97 truck is an automatic?

 

[ls1bmw]

both are autos

 

[Cobraguy]

Then I would round up the 97 OHV harnesses you need. Can't use the 95 stuff because it's EEC-IV and the trans won't operate correctly as Jamie said.

Jamie, haven't you mentioned the ability to use a SOHC ECM on an OHV successfully by some guys? Or is it the opposite way?

 

[410Fortune]

I know of running a SOHC using a OHV computer, basically you ignore the valve cover mounted cam sensor
My buddy Brett did it in his 94 Sport using a 04 Ranger SOHC and 5 speed, it straight MOVES that truck, give my 5.0L BII a run for its $$$
But fitting a SOHC in a Gen I is tighter then the V8!!
He is pulling the engine again to make more room and get it 100% perfect, if you know Brett you know it will look and act factory or better
camburg and other So Cal desert racers are using the SOHC more and more, with OHV computers and 5 speeds or C4
enough so in fact Cullhane now produces a specific 4.0L V6 to C4 bellhousing, no more trying to lcoate a C5 or C3 pinto bellhousing for your C4 swap just need $400 LOL



My info says the cam sensor is used for start up only, some say the PCM uses it to adjust timing, James could probably tell us for sure what the effects are of ignoring it or hopefully removing its functions from the PCM with a tune

aside from that sensor they are just about identical through the years, the SOHC and OHV share the same transmissions, same physical dimensions (short block at least LOL), fuel systems, etc

95 to 97 auto trans is where the problem is, not SOHC to OHV
If you can use a stand alone transmission controller for your 97 auto then you can use a 5 speed computer for your V6 and use the 95 OHV LOL
stand alone controller = $$$$$$$$$ if even avail for the V6 trans
Now you are spending $$$ to make this work, why not spend $$$ towards a simple new SOHC or heck a V8 donor, same amount of work!

I am NOT sure you can run a OHV with a SOHC computer, I dont see why not??

my question would be WHY?? I know I know parts are free in this case
used SOHC from a 02-04 truck is about $400-500 these days, may be worth it

97 was first year and IMO a bad year for the SOHC, however I have seen some go 250K no issues LOL

 

[ls1bmw]

Well after looking and walking back and forth comparing the two I am positive I can make something work. I was even looking into swapping the engine harness from the sohc onto the ohv. as mentioned the only difference is the cam sensor on the valve cover. So I know I can make the engine work now my question is what is the story with the transmissions? If need be I will swap them too. As of yet I am planning on simply putting the OHV in and plugging it in and seeing what happens. If it doesnt work I will swap the ecu's. But I had not planned on a transmission compatability problem.

Also if you cant put 2 and 2 together my name is Ls1 BMW. I have done harder swaps in my day lol. I just wish everything was like in the old days, all you needed was fuel and spark. It wasnt rare to see a chevy in a ford or anything else for that matter.

 

[410Fortune]

its not rare these days either, you just have to run in the correct circles
the LS1 or LS2 swap into a Explorer/Ranger is becoming more and more popular as is OBD-II computer systems and computer controlled automatics

the bottom line is:

95 is OBD-I
97 is OBD-II
et
95 trans will work with 95 computer
97 trans will work with 97 computer

Your best bet is to swap the OHV into the 97 truck and wire it up, there will be several wiring issues, 95 sensors to dont plug and play to a 97 computer, dash

You may end up needing parts from a 97 OHV to make it work, but you wont know until you get the two engines parked side by side

I too have done harder conversions, what BMW platform did you stuff a LS1 into? Would love to see that!

 

[ls1bmw]

I'm moving forward with the swap I will keep everyone informed of any issues I have.

The LS1 is in a M3 (power to weight ratio= crazy).
My list of cars includes: 1991 crown vic (daily driver/winter beater), 1994 mazda mx6 (body kit, jap motor.etc), 1991 bmw m3 (ls1 powered, mustang hydro boost), and a 1973 Pontiac Grand Prix (freshly punched out 455 with lunatti voodoo cam and harland sharp roller rockers)
Some info about me I am 23 years old, live in pittsburgh pa. Have had more cars than I can keep track of. Car are a fun hobby for me and I used my hobby to pay for me education. I graduated in May with my BS/BA with a concentration in Economics. Now I am searching for a "real job" with little luck.

 

[Cobraguy]

Well after looking and walking back and forth comparing the two I am positive I can make something work.

I just LOVE that attitude!!!!

 

[410Fortune]

put everything from the 95 into the 97 is the way to go, but your 97 will now be OBD-I

I was under the impression the trans in the 95 was bad and the engine in the 97 was bad

 

[ls1bmw]

yeah thats what I am doing swaping motors and trans and ecu. 1997 becomes 1995. obd2 becomes obd1. both trans were good, this actually works out much better

 

[410Fortune]

sweet! whatever works, I wonder if it will pass emissions? In CO they wouldnt even know, jsut a sniffer test on the dyno and they check for a cat converter, thats about it.... but in some states this conversion is NOT LEGAL LOL

Your 97 exhaust has 3 or 4 02 sensors, your 95 exhaust has 2
Your 97 has a fuel tank pressure sensor, not sure if the 95 does or not

You will want to use water temp sensors and oil pressure sensors from the 97 engine to work with your 97 dash, there may be some other small wiring changes as the firewall if you want to retain your 97 dash/wiring, etc

just FYI I found a 98 here in CO today with 87K miles, 5.0L V8, entire truck for $600, thats a CHEAP V8 conversion, same amount of work... maybe something you might want to look into in your area, selling the working parts from the 95 would likely pay for a V8 donor truck